CPC Definition - Subclass H04L

Last Updated Version: 2022.05
TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M)
Definition statement

This place covers:

Transmission of signals having been supplied in digital form, e.g. data transmission, telegraphic communication, or methods or arrangements for monitoring.

As the scope of H04L covers a diversity of subject matter, the user is referred to the definitions for the main groups of H04L. The following list is intended to assist the user.

Systems:

Arrangements of general application:

  • security: errors; secrecy, see definition for groups H04L 1/00, H04L 9/00;
  • multiple communications, see definition for groups H04L 5/00, H04L 7/00;
  • network architectures or network communication protocols for network security, see definition for group H04L 63/00
  • real time communication protocols in data switching networks, see definition for group H04L 65/00;
  • network protocols for data switching network services, see definition for group H04L 67/00
References
Limiting references

This place does not cover:

Arrangements applicable to telegraphic or telephonic communication

H04M

Informative references

Attention is drawn to the following places, which may be of interest for search:

Typewriters

B41J

Order telegraphs, fire or police telegraphs

G08B

Visual telegraphy

G08B

Teleautographic systems

G08C

Coding or ciphering apparatus for cryptographic or other purposes involving the need for secrecy

G09C

Spread spectrum techniques in general

H04B 1/69

Selecting

H04Q

Arrangements for detecting or preventing errors in the information received {(correcting synchronisation H04L 7/00)}
Definition statement

This place covers:

Codes for error detection or error correction, i.e. theoretical code construction and coding circuit architecture designs are classified in H04M 13/00; the application of such codes in transmission systems is covered by H04L 1/00 subgroups.

References
Limiting references

This place does not cover:

Correcting synchronisation

H04L 7/00

Informative references

Attention is drawn to the following places, which may be of interest for search:

Computer systems

G06F

Error correction or detection in electrical digital data processing

G06F 11/00 - G06F 11/20

Coin-feed or like apparatus with coded identity card or credit card

G07F 7/08

Error correction in speech coding

G10L 19/005

Codes for error detection or error correction per se, i.e. theoretical code construction and coding circuit architecture designs

H03M 13/00

Transmission

H04B

Diversity Systems for radio transmission systems

H04B 7/02

Error detection and correction for transmission of compressed video (e.g. MPEG)

H04N 19/89, H04N 21/2383

Special rules of classification

Classification into the main group H04L 1/00 itself should be avoided and instead its relevant subgroups should be used by identifying the particular error technique used. If no other group can be assigned for error control applicable to transmission systems, then it may be assigned to this main group.

In addition an Indexing Code can be given under H04L 2001/0092 for network topology, which is of interest to H04L 1/00.

Synonyms and Keywords

In patent documents, the following abbreviations are often used:

AM

Acknowledged Mode

AMC

Adaptive Modulation and Coding

AMR

Adaptive Multirate

ARQ

Automatic Repeat reQuest

BCCH

Broadcast Control Channel

BCH

Broadcast Channel

BER

Bit Error Rate

BLER

Block Error Rate

BPSK

Binary Phase Shift Keying

BW

Bandwidth

C-RNTI

Cell Radio Network Temporary Identity

CDMA

Code Division Multiple Access

CE

Cyclic Extension

CP

Cyclic Prefix

CQI

Channel Quality Indicator

CRC

Cyclic Redundancy Check

CSI

Channel State Information

DCCH

Dedicated Control Channel

DCI

Downlink Control Information

DFT

Discrete Fourier Transform

DL

Downlink

DL-SCH

Downlink Shared Channel

DRA

Dynamic Resource Allocation

DRX

Discontinuous Reception

DTCH

Dedicated Traffic Channel

DTX

Discontinuous Transmission

E-UTRA

Evolved UMTS Terrestrial Radio Access

E-UTRAN

Evolved UMTS Terrestrial Radio Access Network

EPC

Evolved Packet Core

FDD

Frequency Division Duplex

FDM

Frequency Division Multiplexing

FDMA

Frequency Division Multiple Access

FEC

Forward Error Correction

H-ARQ

Hybrid ARQ

HSDPA

High Speed Downlink Packet Access

HSUPA

High Speed Uplink Packet Access

IP

Internet Protocol

IPSec

Internet Protocol Security

LTE

Long Term Evolution

MAC

Medium Access Control

MAC

Message Authentication

NACK

Negative ACK

NAS

Non-Access Stratum

OFDM

Orthogonal Frequency Division Multiplexing

PAPR

Peak-to-Average Power Ratio

PDCCH

Physical Dedicated Control Channel

PDCP

Packet Data Convergence Protocol

PHICH

Physical Hybrid ARQ Indicator Channel

PUCCH

Physical Uplink Control Channel

PUSCH

Physical Uplink Shared Channel

QAM

Quadrature Amplitude Modulation

QPSK

Quadrature Phase Shift Keying

RRC

Radio Resource Control

SDMA

Space (or Spatial) Division Multiple Access

SIMO

Single Input Multiple Output

SIP

Session Initiation Protocol

SIR

Signal-to-Interference Ratio

STC

Space Time Coding

UEP

Unequal error protections

UM

Unacknowledged Mode

VoIP

Voice over Internet Protocol

WCDMA

Wideband Code Division Multiple Access

{Systems modifying transmission characteristics according to link quality, e.g. power backoff (adaptive data allocation for multicarrier modulation H04L 5/0044; controlling transmission power for radio systems H04W 52/04)}
Definition statement

This place covers:

General link adaptation techniques, including power control for non-radio links, and handshaking procedures involving link adaptation.

References
Limiting references

This place does not cover:

Allocation of payload for multicarrier modulation system

H04L 5/0044

Control of transmission power in radio systems

H04W 52/04

Informative references

Attention is drawn to the following places, which may be of interest for search:

Splitting-up the transmission path, e.g. time, frequency etc.

H04L 5/0001

Allocating sub-channels of the transmission path

H04L 5/003

Negotiation of transmission parameters unrelated to channel quality

H04L 5/1438

Adaptation of equalizers (attention: Indexing Code)

H04L 25/03019, H04L 2025/03535

Transmit line pre-equalization, e.g. precoding, MIMO calibration

H04L 25/03343

Multichannel equalizers (attention: Indexing Code)

H04L 2025/03426

Adaptation of timing of transmitters in a network

H04J 3/06

Mode change for facsimile transmission

H04N 1/3333

Network traffic and resource management

H04W 28/00

Communication route selection based on channel quality

H04W 40/12

Wireless resource allocation

H04W 72/04

Special rules of classification

Adaptive techniques are covered by specific subgroups under H04L 1/0001 unless they are other aspects, e.g. frequency hopping, adaptive slew rate, adaptive interleaving, DSL power back-off.

ARQ adaptive retransmission aspects should be classified mainly under the H04L 1/16, H04L 1/18 subgroups.

{by adapting the transmission rate}
Definition statement

This place covers:

The end raw rate at which bits are transmitted through the channel, e.g. after encoding.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Allocation of payload

H04L 5/0044

Management of data rate of a bus

H04L 12/4013

Network nodes adapting their rate to physical link properties

H04L 12/40136

Rate modification

H04L 47/25

Explicit feedback to the source

H04L 47/26

Negotiation of communication rate in wireless communication

H04W 28/22

Power control taking into account the transmission rate

H04W 52/267

{by switching between different modulation schemes}
Definition statement

This place covers:

Also adaptive CDMA and direct sequence spread spectrum is covered by this subgroup.

References
Limiting references

This place does not cover:

Management of data rate of a bus

H04L 12/4013

Network nodes adapting their rate to physical link properties

H04L 12/40136

CDMA system aspects

H04B 1/00

Negotiation of communication rate in wireless communication systems; network traffic / resource management

H04W 28/22

Special rules of classification

Adaptation of modulation is classified in H04L 1/0003 even if line bitrate remains constant, e.g. switch-over from 8-QAM to 8-PSK.

Adaptation of modulation and coding schemes (MCS/AMR) are classifed also under H04L 1/0009.

Particular ARQ physical mapping aspects should be classified mainly under the H04L 1/1893 or H04L 1/1861.

{applied to control information}
Special rules of classification

If the adaptation concerns both control and payload then only H04L 1/0003 is used.

{applied to payload information}
Special rules of classification

If the adaptation concerns both control and payload then only H04L 1/0003 is used.

{by adapting the transmission format}
Definition statement

This place covers:

This group covers adaptive formatting aspects, e.g. adaptive slot allocation, or adaptive packet formats other than coding.

References
Limiting references

This place does not cover:

Adaptation of format of signaling

H04L 1/0029

Channel / frequency assignment

H04W 72/00

{by modifying the frame length}
Definition statement

This place covers:

Frame or packet length adaptation at lower OSI layers.

References
Limiting references

This place does not cover:

Maximum packet size (MTU) for TCP/IP

H04L 47/36

{by adapting the channel coding (H04L 1/1812 takes precedence)}
Definition statement

This place covers:

Also switching between uncoded and coded modes.

References
Limiting references

This place does not cover:

Adapting channel coding for congestion

H04L 47/38

Unequal or adaptive error correction protection

H03M 13/35

Special rules of classification

ARQ redundancy schemes are classified under the subgroups of H04L 1/1812.

Repetition coding per se is classified also in H04L 1/08; other types of codes under the subgroups of H04L 1/004.

Adaptation of space-time coded transmissions, in particular modification of the space-time matrix is classified under the subgroups of H04L 1/0618.

Adaptation of modulation and coding schemes (MCS) are classified also under H04L 1/0003.

{applied to control information}
Special rules of classification

If the adaptation concerns both control and payload then only H04L 1/0009 is used.

{applied to payload information}
Special rules of classification

If the adaptation concerns both control and payload then only H04L 1/0009 is used.

{Rate matching, e.g. puncturing or repetition of code symbols}
Definition statement

This place covers:

The coding rate must be adapted in rate matching operations for link adaptation.

Special rules of classification

Use of multiple puncturing patterns is covered by H04L 1/0068; general rate matching without regard to link quality is covered H04L 1/0067.

{by adapting the source coding}
References
Limiting references

This place does not cover:

Adaptive speech coding per se, no transmission involved

G10L 19/00

Adaptive video coding per se, no transmission involved

H04N 19/10

{characterised by the adaptation strategy}
Definition statement

This place covers:

This class is used for special adaptation strategies for adopting a transmission mode, e.g. select an MCS mode, which do not fall within its subclasses. For example, use of special utility or cost functions is classified here.

{involving special memory structures, e.g. look-up tables}
Definition statement

This place covers:

This class is used for uncommon memory structures, e.g. switching tables, look-up tables and the like.

{where the mode-switching is based on Quality of Service requirement}
Definition statement

This place covers:

Guarantee of QoS and interaction of QoS parameters of higher layers and of the physical and data link layers. Adaptation takes into account types of data, e.g. real-time data.

References
Limiting references

This place does not cover:

Wireless network traffic management

H04W 28/02

{based on latency requirement}
Special rules of classification

Latency aspects per se should be classified only here and not in any higher subgroups.

{in which mode-switching is based on a statistical approach}
Definition statement

This place covers:

Special statistical approaches for mode-switching including future system or channel conditions mode-switching decision, e.g. calculation of confidence intervals or sequential testing for early decisions.

{Algorithms with memory of the previous states, e.g. Markovian models}
Definition statement

This place covers:

Algorithms explicitly using Markov chains.

{in which the algorithm uses adaptive thresholds}
Definition statement

This place covers:

Algorithms in which the adaptation thresholds themselves are adapted according to e.g. state of transmitter or receiver.

{in which mode-switching is influenced by the user}
Definition statement

This place covers:

E.g. during the negotiation phase.

References
Limiting references

This place does not cover:

Re-negotiation phase of parameters unrelated to channel quality

H04L 5/1438

{characterised by the signalling}
Definition statement

This place covers:

Signaling conveying adaptation commands or channel quality indicators, scheduling and formatting aspects thereof.

References
Limiting references

This place does not cover:

Signaling for administration of a divided path

H04L 5/0091

MIMO systems with feedback

H04B 7/0417

Antenna switching / beamforming based on receiver feedback

H04B 7/061, H04B 7/0619

Monitoring or testing of receivers with feedback of measurements to the transmitter

H04B 17/24

Measuring or estimating channel quality parameters

H04B 17/309

Special rules of classification

The appropriate sub-group should be assigned and the main sub-class be avoided.

Signal quality per se is classified in H04L 1/20.

{Transmission of mode-switching indication}
Definition statement

This place covers:

Both for forward and reverse direction.

{Transmission of channel quality indication}
References
Limiting references

This place does not cover:

Monitoring or testing of receivers with feedback of measurements to the transmitter

H04B 17/24

{Formatting}
Definition statement

This place covers:

How the actual signaling is conveyed.

Special rules of classification

The appropriate sub-group should be assigned and the main sub-class be avoided. Mere error control coding of signaling is not assigned by this class.

{Reduction of the amount of signalling, e.g. retention of useful signalling or differential signalling (power control H04W 52/04)}
References
Limiting references

This place does not cover:

Wireless Transmission Power Control

H04W 52/04

Special rules of classification

Protection of CQI (channel quality indicator) or TFCI (or transport format combination indicator) with error control is classified in H04L 1/0072.

{Multiple signaling transmission (H04L 1/1664, F15 take precedence)}
References
Limiting references

This place does not cover:

Details of the supervisory signal being transmitted together with payload signals; piggybacking

H04L 1/1664

Systems acting by means of fluids in general; Fluid-pressure actuators, e.g. servo-motors; Details of fluid-pressure systems, not otherwise provided for

F15

Special rules of classification

The class should not be assigned if the commands include an acknowledgement indication.

Piggybacked acknowledgements or transmission of command with acknowledgement indication is classified in H04L 1/1664 , H04L 1/1671 .

{Without explicit signalling}
Special rules of classification

Implicit signaling is not classified here either but in relevant subgroups under H04L 1/0033, H04L 1/0036.

{arrangements specific to the transmitter}
Definition statement

This place covers:

Specific parameters of transmitter aspects, i.e. circuit or computer-based implementation, e.g. amplifying circuit, etc. according to channel quality.

Special rules of classification

The class should be assigned only if its subclass is not relevant.

{where the transmitter decides based on inferences, e.g. use of implicit signalling}
Definition statement

This place covers:

Mode switching based on ACK/NACK indications (ACK/NACKs are used as derivative channel quality indicators).

{arrangements specific to the receiver}
Definition statement

This place covers:

Specific parameters of receiver aspects, i.e. circuit or computer-based implementation, e.g. demodulator, etc. according to channel quality.

Special rules of classification

The class should be assigned only if any subclass is not relevant.

{Blind format detection (for detection of modulation format H04L 27/0012)}
References
Limiting references

This place does not cover:

Identification of modulation type

H04L 27/0012

CDMA code identification

H04B 1/707

{other detection of signalling, e.g. detection of TFCI explicit signalling (H04L 1/0046, H04L 27/0012 and H04L 25/0262 take precedence)}
References
Limiting references

This place does not cover:

Code rate detection or code type detection

H04L 1/0046

Arrangements for detecting the data rate of an incoming signal

H04L 25/0262

Arrangements for identifying the type of modulation

H04L 27/0012

Special rules of classification

Code rate detection of code type detection are classified in H04L 1/0046.

{by using forward error control (H04L 1/0618 takes precedence; coding, decoding or code conversion, for error detection or correction H03M 13/00)}
Definition statement

This place covers:

Application of FEC codes in transmission systems.

References
Limiting references

This place does not cover:

Space-time coding

H04L 1/0618

Error correction in synchronization

H04L 7/00

Error correction or detection in electrical digital data processing

G06F 11/00 - G06F 11/20

Error correction in speech coding

G10L 19/005

Error detection/correction (code construction per se, coding and decoding architectures)

H03M 13/00

Codes for error detection or error correction per se

H03M 13/00

Error correction for video transmission (e.g. MPEG)

H04N 19/89

Special rules of classification

Adaptive FEC is classified in H04L 1/0009.

Space-time/frequency coding/decoding is classified in H04L 1/0618, H04L 1/0606

Repetition coding is classified in H04L 1/08.

Hybrid ARQ redundancy schemes (ARQ combined with FEC) are classified under the subgroups of H04L 1/1812.

{Arrangements at the transmitter end}
Definition statement

This place covers:

Hardware circuit design or functional computer-implemented arrangements.

{Encoding specially adapted to other signal generation operation, e.g. in order to reduce transmit distortions, jitter, or to improve signal shape (H04L 1/0067 takes precedence)}
Definition statement

This place covers:

The FEC encoding operation is specifically designed by taking into account other signal generation operations (e.g. properties of the modulator or local oscillator).

References
Limiting references

This place does not cover:

Rate matching

H04L 1/0067

For PSK signal shaping, e.g. trellis shaping, coset coding

H04L 27/186

QAM signal shaping, e.g. trellis shaping, coset coding

H04L 27/3416

Special rules of classification

Classes H04L 1/0058, H04L 1/006, H04L 1/0067 are considered first before giving the above subclass.

{Arrangements at the receiver end}
Definition statement

This place covers:

Hardware circuit design or functional computer-implemented arrangements.

{Code rate detection or code type detection (H04L 1/0038 takes precedence; detection of the data rate H04L 25/0262; for packet format H04L 1/0091)}
References
Limiting references

This place does not cover:

Blind format detection

H04L 1/0038

Packet format detection

H04L 1/0091

Data rate detection

H04L 25/0262

Special rules of classification

Adaptive code rate or code type detection is classified in H04L 1/0038.

Packet format detection is classified in H04L 1/0091.

{Decoding adapted to other signal detection operation (in conjunction with sequence estimation or equalization H04L 25/03286)}
Definition statement

This place covers:

The FEC encoding operation is specifically designed by taking into account other signal generation operations (e.g. properties of the demodulator, sensitivity to errors of later signal processing stages).

References
Limiting references

This place does not cover:

Sequence estimation or equalization

H04L 25/03286

{in conjunction with detection of multiuser or interfering signals, e.g. iteration between CDMA or MIMO detector and FEC decoder (for spatial equalizer H04L 25/03286)}
References
Limiting references

This place does not cover:

Synchronization based on error correcting/detecting codes

H04L 7/048

with channel-decoding circuitry

H04L 25/03286

In conjunction with spatial equalization

H04L 25/03343, H04L 2025/03426

{Iterative decoding, including iteration between signal detection and decoding operation}
References
Limiting references

This place does not cover:

Turbo equalization

H04L 25/03171

Turbo coding and decoding per se

H03M 13/2957

{Maximum-likelihood or sequential decoding, e.g. Viterbi, Fano, ZJ algorithms}
References
Limiting references

This place does not cover:

Sequence estimation, e.g. Viterbi decoding arrangements

H03M 13/39 - H03M 13/41

{Systems characterized by the type of code used (H04L 1/08 takes precedence)}
References
Limiting references

This place does not cover:

By repeating transmission, e.g. Verdan system

H04L 1/08

Special rules of classification

Repetition coding is classified in H04L 1/08.

{Block codes (H04L 1/0061, H04L 1/0064 take precedence)}
Definition statement

This place covers:

Block codes such as Reed-Solomon codes, LDPC codes, etc.

References
Limiting references

This place does not cover:

Error detection codes

H04L 1/0061

Concatenated codes

H04L 1/0064

Special rules of classification

Classes H04L 1/0061 and H04L 1/0064 take precedence.

{Block-coded modulation}
References
Limiting references

This place does not cover:

Coded modulation with block coding per se

H03M 13/251

{Trellis-coded modulation}
References
Limiting references

This place does not cover:

Coded modulation with trellis coding per se

H03M 13/256

{Rate matching (H04L 1/0013 and H04L 1/08 take precedence)}
References
Limiting references

This place does not cover:

By repeating transmission, e.g. Verdan system

H04L 1/08

Special rules of classification

Adaptive rate matching according to link quality is covered by H04L 1/0013.

Repetition coding is covered by H04L 1/08.

{Puncturing patterns}
Definition statement

This place covers:

Puncturing patterns (adaptive and non-adaptive).

{Unequal error protection (for format H04L 1/0078; for codes per se H03M 13/35)}
References
Limiting references

This place does not cover:

Avoidance of errors by organising the transmitted data in a format specifically designed to deal with errors

H04L 1/0078

Unequal error protection

H03M 13/35

Special rules of classification

Unequal error protection formatting arrangements is covered by H04L 1/0086.

General aspects of UEP is covered by old Indexing Code H04L 2001/0098.

{Use of interleaving (interleaving per se H03M 13/27)}
Definition statement

This place covers:

Use of interleavers, which interchange data elements in the time domain in transmission systems.

Relationships with other classification places

Diversity arrangements, see H04L 1/02.

References
Limiting references

This place does not cover:

Assignment of physical channels and/or subcarriers

H04L 5/00, H04L 27/26

Interleaving per se and its memory designs

H03M 13/27

Spatial/frequency diversity for radio communication

H04B 7/02

Special rules of classification

Turbo coding interleavers are not classified here since they are considered integral part of the turbo coder.

Non-adaptive formatting arrangements is covered by H04L 1/0086.

{Error control for data other than payload data, e.g. control data}
Special rules of classification

Adaptive FEC for control data is covered by H04L 1/001.

{Special arrangements for feedback channel}
Definition statement

This place covers:

Details of FEC of feedback such as CQI, ACK.

Special rules of classification

ACK/NACK repetition coding is covered by H04L 1/1858.

{Transmission of coding parameters to receiver (H04L 1/0023 takes precedence)}
Definition statement

This place covers:

Details concerning transmission of FEC related parameters related to signaling information.

Special rules of classification

Transmission of signaling for adaptation purposes is covered by H04L 1/0023.

{Distributed coding, e.g. network coding, involving channel coding (coding in both space and time H04L 1/0618; cooperative diversity H04B 7/022)}
Definition statement

This place covers:

Details of error control at intermediate node, e.g. exclusive OR signal coding or stronger re-encoding arrangements at relay.

References
Limiting references

This place does not cover:

Cooperative diversity

H04B 7/022

Active relay systems

H04B 7/15

Special rules of classification

Coding in both space and time is covered by H04L 1/0618.

Topology aspect is covered by H04L 2001/0097.

{Avoidance of errors by organising the transmitted data in a format specifically designed to deal with errors, e.g. location (forward error control, e.g. FEC, CRC H04L 1/004; adaptive formatting H04L 1/0006; mappings H04L 27/00)}
References
Limiting references

This place does not cover:

Physical mapping

H04L 27/00

Special rules of classification

Adaptive formatting is covered by H04L 1/0006.

FEC coding, e.g. CRC is covered by H04L 1/004.

{Formats for control data (H04L 1/16 takes precedence; training sequences H04L 25/00 and H04L 27/00)}
References
Limiting references

This place does not cover:

By using return channel in which the signals are sent back to the transmitter to be checked

H04L 1/16

Baseband systems

H04L 25/00

Modulated-carrier systems

H04L 27/00

Special rules of classification

Acknowledgement formats is covered by H04L 1/16 and H04L 1/1607.

{fields explicitly indicating existence of error in data being transmitted, e.g. so that downstream stations can avoid decoding erroneous packet; relays}
Special rules of classification

Arrangements for preventing errors in the return channel, e.g. handshaking are covered by Indexing Code H04L 2001/125.

{Unequal error protection (H04L 27/00 and H04L 1/004 take precedence for layer 1/2 aspects, e.g. bit loading)}
References
Limiting references

This place does not cover:

by using forward error control

H04L 1/004

Bit loading is covered by

H04L 5/0046

Constellation mapping aspects

H04L 27/00

Special rules of classification

UEP for coding is covered by H04L 1/007.

General aspects of UEP is covered by old Indexing Code H04L 2001/0098.

{arrangements specific to transmitters}
Definition statement

This place covers:

Hardware circuit design or functional computer-implemented functions.

{arrangements specific to receivers, e.g. format detection (detection of data rate H04L 25/0262; detection of coding rate H04L 1/0046)}
Definition statement

This place covers:

Hardware circuit design or functional computer-implemented functions.

References
Limiting references

This place does not cover:

Data rate detection is covered by

H04L 25/0262.

Special rules of classification

Code rate detection is covered by H04L 1/0046.

by diversity reception
Definition statement

This place covers:

Space-time coding techniques (i.e. for radio) are classified beneath, see relevant subclasses.

In addition, non-radio diversity arrangements involving redundant, simultaneous signal transmission.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Radio diversity arrangements (except space-time coded arrangements) are covered by

H04B 7/02

Special rules of classification

The class should be assigned only if any subclass is not applicable.

using frequency diversity
References
Limiting references

This place does not cover:

Radio frequency diversity is covered by

H04B 7/12

{Space-time modulation}
Definition statement

This place covers:

Arrangements with constellation plane partitioning taking space-time diversity into account in equivalence to trellis coded modulation in non-diversity schemes.

{Space-time coding}
References
Limiting references

This place does not cover:

Radio space diversity arrangements

H04B 7/06, H04B 7/08

{Transmitter arrangements}
Definition statement

This place covers:

Hardware circuit design or functional computer-implemented arrangement.

{Receiver arrangements}
Definition statement

This place covers:

Hardware circuit design or functional computer-implemented arrangement.

References
Limiting references

This place does not cover:

Sphere detection

H04L 25/03242

{block codes}
Definition statement

This place covers:

Transmitted space-time matrices that are considered each as one block coded entity.

Special rules of classification

For symbol block coding prior to space-time matrix transmission H04L 1/0057.

{by means of convolutional encoding}
Special rules of classification

For symbol convolutional coding prior to space-time matrix transmission H04L 1/0059.

{Limited orthogonality systems}
Definition statement

This place covers:

Semi-orthogonal space-time matrix arrangements to increase the transmission rate.

{characterised by the signaling}
Definition statement

This place covers:

Signaling pertaining to the space-time matrix.

Special rules of classification

For normal adaptive transmissions H04L 1/0001.

by repeating transmission, e.g. Verdan system {(H04L 1/1858 and H04L 1/189 take precedence)}
References
Limiting references

This place does not cover:

Transmission or retransmission of more than one copy of an acknowledgement message

H04L 1/1858

Transmission or retransmission of more than one copy of a message

H04L 1/189

Informative references

Attention is drawn to the following places, which may be of interest for search:

Adaptive and non-adaptive rate matching

H04L 1/0013, H04L 1/0067

by using return channel
Special rules of classification

Arrangements for preventing errors in the return channel, e.g. handshaking are covered also by Indexing Code H04L 2001/125.

in which the signals are sent back to the transmitter to be checked {; echo systems}
References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Loop-back testing

H04L 1/243

Echo cancellation

H04B 3/20

in which the return channel carries supervisory signals, e.g. repetition request signals
References
Limiting references

This place does not cover:

Status reports for improving the reliability of multicast or broadcast data in data switching networks

H04L 12/1863

{Group acknowledgement, i.e. the acknowledgement message defining a range of identifiers, e.g. of sequence numbers}
Definition statement

This place covers:

Explicit indications of ranges of acknowledged data packets, e.g. sequence numbers SN:5 to 16, 23 to 25. Rules may be involved to further compress the sequence number or other signaling.

{List acknowledgements, i.e. the acknowledgement message consisting of a list of identifiers, e.g. of sequence numbers (H04L 1/1614 takes precedence)}
Special rules of classification

Bitmaps where list acknowledgements appear as 0s and 1s are in H04L 1/1614.

Automatic repetition systems, e.g. van Duuren system {; ARQ protocols}
References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Implementation or adaptation of Internet protocol [IP], of transmission control protocol [TCP] or of user datagram protocol [UDP]

H04L 69/16

{Details of sliding window management}
References
Limiting references

This place does not cover:

Window size / update for TCP/IP

H04L 47/10

{for semi-reliable protocols, e.g. for less sensitive applications such as streaming video (buffer level management for video bitstream receiver H04N 21/44004)}
References
Limiting references

This place does not cover:

Buffer level management for video bitstream receiver.

H04N 21/44004

{Transmission or retransmission of more than one copy of acknowledgement message}
References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Repetition coding in general

H04L 1/08

{Physical mapping arrangements (for ACK signaling see also H04L 5/0053)}
Definition statement

This place covers:

Constellation / mapping rearrangements due to retransmissions, and mapping of receiver-initiated transmissions to resource blocks.

References
Limiting references

This place does not cover:

Allocation of signaling

H04L 5/0053

{ARQ related signaling (H04L 1/1607 takes precedence)}
Special rules of classification

Acknowledgement signaling per se is classified in H04L 1/1607.

{Details of sliding window management}
References
Limiting references

This place does not cover:

Window size / update for TCP/IP

H04L 47/10

{for semi-reliable protocols, e.g. for less sensitive applications like streaming video (buffer level management for video bitstream control arrangements H04N 21/44004)}
References
Limiting references

This place does not cover:

Buffer level management for video bitstream receiver

H04N 21/44004

{Transmission or retransmission of more than one copy of a message}
References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Repetition coding in general

H04L 1/08

{Physical mapping arrangements (physical resource mapping in general H04L 5/00)}
Definition statement

This place covers:

Constellation / mapping rearrangements due to retransmissions, and mapping of transmitter-initiated transmissions to resource blocks.

References
Limiting references

This place does not cover:

Physical resource mapping in general

H04L 5/00

using signal quality detector
References
Limiting references

This place does not cover:

Measurement characteristics of individual pulses

G01R 29/02

Measurement of noise, signal-to-noise

G01R 29/26

Measurement of signal quality by testing

G01R 31/31708

Measurement of optical signal-to-noise, bit error rate, quality factor

H04B 10/07953

Measuring or estimating channel quality parameters

H04B 17/309

{Frame classification, e.g. bad, good or erased (frame indication per se H04L 1/0082)}
Special rules of classification

Frame indication per se H04L 1/0082.

{jitter monitoring}
References
Limiting references

This place does not cover:

Measurement of noise, signal-to-noise

G01R 29/26

Jitter measurement by testing

G01R 31/31709

using redundant apparatus to increase reliability
Definition statement

This place covers:

E.g. redundant stand-by links.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Redundancy in electrical buses

H04L 12/40176

Redundant control systems

G05B 9/03

Error detection / correction

G06F 11/08

Redundant systems in computer networks

G06F 11/16

Switching spare elements

G06F 11/20

Other transmission systems with redundant channels

H04B 1/74

Testing correct operation
Definition statement

This place covers:

Testing correct operation.

References
Limiting references

This place does not cover:

Testing / monitoring arrangements

H04L 43/50, H04L 43/00

Measurement of non-linear distortion

G01R 23/20

Measuring characteristics of individual pulses, e.g. deviation from pulse flatness, rise time, duration

G01R 29/02

Arrangements for testing circuits and fault location

G01R 31/00

Testing storage memories

G11C 29/00

Testing of line transmission systems

H04B 3/46

Testing for optical arrangements

H04B 10/07

Testing of transmitters / receivers

H04B 17/00

SDH/SONET monitoring

H04J 3/14

Monitoring / testing of exchanges

H04M 3/22

Testing arrangements for wireless transmission

H04W 24/00

{at the transmitter, using a loop-back}
Special rules of classification

Echo systems are in H04L 1/14.

Arrangements affording multiple use of the transmission path
Definition statement

This place covers:

Arrangements for dividing a transmission path, for allocating sub-channels, signalling for multiple channel indication and duplex/half-duplex systems.

This group works at the physical layer, for wireless or line communications (ADSL).

The arrangements for dividing the transmission path involve multiple access techniques capable of supporting multiple users by sharing the available system resources. Examples of such multiple-access techniques include Frequency Division Multiple Access (FDMA) systems, Orthogonal FDMA (OFDMA) systems, multicarrier Code Division Multiple Access (multicarrier CDMA) systems, i.e. any combination of multicarrier signals and a code division.

An OFDM system may implement a radio technology such as Evolved UTRA (E-UTRA), Ultra Mobile Broadband (UMB), IEEE 802.11 (Wi-Fi), IEEE 802.16 (WiMax), IEEE 802.20, Flash-OFDM, etc.

3GPP Long Term Evolution (LTE) is a release of UMTS that uses E-UTRA, which employs OFDM on the downlink and SC-FDMA on the uplink.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Data switching networks

H04L 12/00

Systems using multi-frequency codes

H04L 27/26

Multicarrier modulation techniques

H04L 27/2626

Multicarrier demodulation techniques

H04L 27/2647

Multicarrier synchronisation aspects

H04L 27/2655

Spread spectrum techniques in general

H04B 1/69

Frequency hopping for spread spectrum

H04B 1/713

Conditioning for two-way transmission in general

H04B 3/20

Spatial multiplexing for diversity systems (the same signal is transmitted by the different antennas)

H04B 7/0697

Multiplex communication in general

H04J

Time division multiple access (TDMA)

H04J 3/00

Orthogonal CDMA (i.e. using Walsh codes)

H04J 11/00

Code division multiple access (CDMA)

H04J 13/00

Code allocation

H04J 13/16

Wireless communication networks; Local resource management

H04W 72/00

Special rules of classification

When the multiple access scheme relies on the use of multicarrier signals, and if what is important is how the signal is modulated/demodulated, or "hardware" aspects in the transmitter or the receiver to produce or recover (like synchronisation) such signal or aspects related to the peak power reduction, then the classes under H04L 27/2601 are relevant. Otherwise, to indicate that the signal involved is, for example, an OFDM signal, then the class under H04L 5/0007 is used instead.

Subgroups H04L 5/22, H04L 5/225, H04L 5/24, H04L 5/245, H04L 5/26 are inactive. The classification should be done in H04J 3/00.

Glossary of terms

In this place, the following terms or expressions are used with the meaning indicated:

ADSL

Asymmetric Digital Subscriber Line

DMT

Discrete Multi-Tone

MC-CDMA

Multicarrier CDMA

OFDM

Orthogonal Frequency Division Multiplexing

OFDMA

Orthogonal Frequency Division Multiple Access

SC-FDMA

Single-Carrier Frequency Division Multiple Access

CC

Component Carrier

CoMP

Cooperative Multi-point

FDM

Frequency Division Multiplexing

FDMA

Frequency Division Multiple Access

IFDMA

Interleaved Frequency Division Multiple Access

MIMO

Multiple-Input Multiple-Output

PRB

Physical Resource Block

RA

Resource Allocation

SDMA

Spatial Division Multiple Access

SRS

Sounding Reference Signal

TDD

Time Division Duplex

Synonyms and Keywords

In patent documents, the following words/expressions are often used with the meaning indicated:

"pilot signals"

"Reference Signals" or "training signals" or "sounding signals".

"persistent allocation"

that the resources allocated to the user equipment (UE) are valid until the UE receives another allocation which will then override the previous one. This would typically happen in case the channel conditions have changed (or AMR codec changes) and, thus, the previous allocation would no longer be suitable for the user.

{Arrangements for dividing the transmission path (duplexing H04L 5/14; multiplexing of different sources on one path H04J)}
Definition statement

This place covers:

This group answers the question "How is the transmission path split up?". Since the signals are digital, it is considered that there is always a time dimension, and thus, the minimum number of dimensions is two.

References
Limiting references

This place does not cover:

Two-way operation using the same type of signal

H04L 5/14

Multiplex communication in general

H04J

{the frequencies being orthogonal, e.g. OFDM(A), DMT}
Definition statement

This place covers:

The case of an access method allowing multiple users to share the same frequency band by subdividing the band into orthogonal frequency channels. If the frequencies are not orthogonal then the group H04L 5/0005 should be given instead.

Frequency hopping for multicarrier signals, SC-FDMA and IFDMA are also covered by H04L 5/0007.

{in which a distinct code is applied, as a temporal sequence, to each frequency}
Special rules of classification

This group should contain the cases of spreading codes in the time domain, where chips of the code are applied in sequence, once at a time, to each of the subcarriers.

{in which one code is applied, as a temporal sequence, to all frequencies}
Special rules of classification

This group should contain the cases of spreading codes in the time domain, where each frequency sees the same spreading code (for example, multicarrier DS-CDMA).

{in which codes are applied as a frequency-domain sequences, e.g. MC-CDMA}
Special rules of classification

This group should contain the cases of spreading codes in the frequency domain. Each chip of the spreading code is transmitted through a different subcarrier.

{Time-frequency-space}
Definition statement

This place covers:

The combination OFDM and MIMO; or frequency reuse.

{Variable division (signaling therefor H04L 5/0092)}
Definition statement

This place covers:

Changes from time-frequency to time-frequency-space, for example.

References
Limiting references

This place does not cover:

Indication of how the channel is divided

H04L 5/0092

{Arrangements for allocating sub-channels of the transmission path}
Definition statement

This place covers:

Sub-channels are what the path is split up into according to H04L 5/0001.

{Distributed allocation, i.e. involving a plurality of allocating devices, each making partial allocation}
Definition statement

This place covers:

This group answers the question of "Who makes the allocation?". Cooperative allocation (for example in CoMP systems or cognitive radio systems or when dealing with ICIC, Inter-cell Interference Cancellation) is classified under H04L 5/0032, which implies a plurality of base stations that cooperates or exchanges information to perform the allocation.

{Inter-user or inter-terminal allocation}
Definition statement

This place covers:

The allocation for plurality of users, thus, to indicate which user gets what.

{intra-user or intra-terminal allocation}
Definition statement

This place covers:

Single user case, what a single user does with its resources.

{allocation of payload}
Definition statement

This place covers:

Allocation of payload or data in the available subchannels.

{Determination of how many bits are transmitted on different sub-channels}
Definition statement

This place covers:

The case of having different modulations in the different subcarriers.

{Allocation of pilot signals, i.e. of signals known to the receiver}
Definition statement

This place covers:

Pilot or reference signal patterns.

{Allocation of signaling, i.e. of overhead other than pilot signals}
Definition statement

This place covers:

Where (for example, in the time-frequency grid) to send ACK/NacK signals, CQI (Channel Quality Indicator) signals and in general any control signalling which is not a known signal to the receiver (pilots, sounding reference symbols, SRS, or synchronisation signals are known to the receiver and they are classified under H04L 5/0048). In order words, which physical resources are used for signalling.

{Rate requirement of the data, e.g. scalable bandwidth, data priority}
Special rules of classification

According to QoS (Quality of Service) is also classified here.

{Timing of allocation}
Definition statement

This place covers:

The subgroups answer the question "How often the allocation is updated?". For Persistent allocation (if the update is due to channel conditions change, then H04L 5/0085), fixed allocation (H04L 5/008).

{Indication of how the channel is divided}
Definition statement

This place covers:

How the channel is divided, for instance, for indicating that the whole frequency band is divided into a certain number of subcarriers, or that the base station informs the mobile how according to H04L 5/0001 the channel is divided. Both uplink or downlink.

{Indication of how sub-channels of the path are allocated}
Definition statement

This place covers:

The signalling of the Content of the allocation. For example, which carriers are allocated, how many bits are allocated to each subcarrier, etc. Both uplink or downlink.

the signals being represented by different frequencies (combined with time-division multiplexing H04L 5/26)
Definition statement

This place covers:

FDM. Different data signals for transmission on a single communications channel are multiplexed, whereby each signal (single carrier) is assigned a non-overlapping frequency range within the main channel.

References
Limiting references

This place does not cover:

combined with the use of different frequencies

H04L 5/26

each combination of signals in different channels being represented by a fixed frequency
References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Frequency regulation arrangements

H04L 27/16

Two-way operation using the same type of signal, i.e. duplex
Definition statement

This place covers:

ADSL systems. FDD systems.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Repeaters for converting two wires to four wires

H04L 25/22

Reducing echo effects or singing

H04B 3/20

Selecting arrangements

H04Q 3/00

{for modulated signals (H04L 5/1469 takes precedence)}
Definition statement

This place covers:

For example, Zipper (a time-synchronised frequency division duplex implementation of discrete multi-tone, DMT, modulation).

using different combinations of lines, e.g. phantom working
References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Arrangements for coupling to multiple lines, e.g. for differential transmission

H04L 25/0272

Phantom interconnection between telephone switching centres

H04M 7/08

Arrangements for synchronising receiver with transmitter {(synchronisation of generators of electric oscillations or pulses H03L 7/00)}
Definition statement

This place covers:

Bit or symbol synchronization of digital receivers.

Synchronization of packets or bursts in radio or optical transmission.

Bit or symbol synchronization of digital recording system, if this system is not specially adapted to recording.

Bit or symbol synchronization of in a memory system, if the system is not specially adapted to memorizing.

References
Limiting references

This place does not cover:

Synchronisation of generators of electric oscillations or pulses

H03L

Synchronisation of automatic control of frequency or phase

H03L 7/00

Informative references

Attention is drawn to the following places, which may be of interest for search:

Synchronization of OFDM

H04L 27/2601

Synchronisation of electronic time-pieces

G04G 7/00

Recording

G11B 20/00

Memory systems

G11C

Synchronization in CDMA

H04B 1/69

Synchronization of frames and in TDM networks, including timestamps

H04J 3/06

Synchronising in TV system

H04N 5/04

Regeneration of clock signals for television systems

H04N 7/0352

Glossary of terms

In this place, the following terms or expressions are used with the meaning indicated:

OFDM

Orthogonal Frequency Division Multiplexing

CDMA

Code Division Multiple Access

TDM

Time Division Multiplex

PLL

Phase Locked Loop

DLL

Delay Locked Loop

{Initialisation of the receiver (H04L 7/0075 and H04L 7/10 take precedence)}
Definition statement

This place covers:

Calibration of synchronizers.

Special rules of classification

H04L 7/0075 and H04L 7/10 take precedence.

{Synchronisation information channels, e.g. clock distribution lines}
Definition statement

This place covers:

Source synchronous systems.

Transmission of clock on a dedicated channel, line or link.

Clockwise and counterclockwise clock distribution.

Clock distributed as sinus or standing wave

References
Limiting references

This place does not cover:

Clock distribution in computers or integrated circuits

G06F 1/04

Clock distribution in semiconductor memory systems

G11C

Informative references

Attention is drawn to the following places, which may be of interest for search:

{by comparing receiver clock with transmitter clock}
Definition statement

This place covers:

The received clock is compared with a local clock of the receiver. The comparison controls the synchronisation.

References
Limiting references

This place does not cover:

The data is not used in the detection of the error or in other parts of the synchronisation. Using the received data for synchronization is classified under H04L 7/02 or H04L 7/04.

Special rules of classification

Synchronization of received clock and local clock by PLL or DLL, H03L 7/00 takes precedence.

{correction of synchronization errors}
Definition statement

This place covers:

Correction of the synchronisation error in receiver or transmitter

References
Limiting references

This place does not cover:

Detection of synchronisation error by means of signal transition, e.g. PLL

H04L 7/033

{correction by interpolation}
Definition statement

This place covers:

Applies also to clock interpolation in the transmitter for the purpose of synchronisation.

Special rules of classification

If clock interpolation for synchronization is performed at the transmitter, also H04L 7/0091 should be applied.

{interpolation of clock signal}
Definition statement

This place covers:

Covers interpolation of received clock of source synchronous systems.

Covers interpolation of local, e.g. interpolation among several local phase shifted clocks.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Selection out of many clock phases for synchronisation, e.g. phase picking, if the control uses transitions of the received data

H04L 7/0337

{interpolation of received data signal}
References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Detection of synchronization error by monitoring at least on equalizer tap weight

H04L 7/0058

Equalizers per se

H04L 25/03

Rate adaption

H04L 25/05

Digital Filters, e.g. FIR Filter

H03H 17/06

Synonyms and Keywords

In patent documents, the following abbreviations are often used:

SRC

Sample Rate Conversion

{Correction by delay}
Definition statement

This place covers:

Delay of other signals than clock or information data, e.g. delay of additional signalling among transmitter and receiver

References
Limiting references

This place does not cover:

Delay of command signals specific for memory systems, e.g. strobe signal DQS

G11C

Informative references

Attention is drawn to the following places, which may be of interest for search:

Selection out of many clock phases for synchronisation, e.g. phase picking, if the control uses transitions of the received data

H04L 7/0337

{Delay of clock signal}
Definition statement

This place covers:

Delay of a received clock signal, e.g. a clock signal received by via a clock line. Delay of a clock signal in the receiver or in the transmitter

References
Limiting references

This place does not cover:

H04L 7/0337 takes precedence if the synchronization makes use of the transitions of the received data signal

{Delay of data signal}
Definition statement

This place covers:

Delay of a received data signal.

Delay of the data signal in the transmitter, e.g. the transmitter receiver an information regarding the synchronisation error.

References
Limiting references

This place does not cover:

H04L 7/0337 takes precedence if the synchronization makes use of the transitions of the received data signal

{Correction by an elastic buffer}
Definition statement

This place covers:

An elastic buffer or FIFO is used to compensate the synchronisation error

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Rate adaption, e.g. from 8 kHz to 9.2 kHz

H04L 25/05

Elastic buffers in computer systems

G06F 5/06

Synchronisation using elastic buffers in time multiplexing systems or packet multiplexing systems

H04J 3/062

Glossary of terms

In this place, the following terms or expressions are used with the meaning indicated:

FIFO

First-In First-Out buffer

{Detection of the synchronisation error by features other than the received signal transition (by means of signal transition H04L 7/033)}
Definition statement

This place covers:

Synchronization by sample processing, e.g. Wave-Difference-Method.

Determination of gradients.

References
Limiting references

This place does not cover:

By means of signal transition

H04L 7/033

Special rules of classification

Synchronization by determining maximum of first derivation of sampled waveform as estimate of zero or threshold crossing: H04L 7/0334 takes precedence.

Synchronization by determining zero of the second derivation of the sampled waveform: H04L 7/007 takes precedence.

{detection of error based on equalizer tap values}
Definition statement

This place covers:

Detection of error by monitoring of equalizer taps, e.g. center tap tracking.

{detection of error based on data decision error, e.g. Mueller type detection}
Definition statement

This place covers:

Error of the data decision, e.g. subtracting input from output of the decision device, to control synchronisation.

Timing Function: Combining of the error with input signals or not decided symbols.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Synchronization based on data transition by sample processing of at least three levels, e.g. soft decisions.

H04L 7/0334

{detection of error based on transmission code rule}
Definition statement

This place covers:

Synchronization using properties of line codes like Manchester, PPM or RZ. Synchronization using properties of block codes as 4b/5b.

Also covers violations of such coding rules to transmit synch information.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Line coding

H04L 25/4902

Block coding mb/nb

H04L 25/4908

Glossary of terms

In this place, the following terms or expressions are used with the meaning indicated:

PPM

Pulse Position Modulation

{detection of error based on maximum signal power, e.g. peak value, maximizing autocorrelation}
Definition statement

This place covers:

Covers SCCL detectors, Sample Correlate Choose Largest.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Synchronization by maximum signal power on symbols known to the receiver, e.g. fixed synchronization information or UW. Correlation of UW for synchronization

H04L 7/042

Glossary of terms

In this place, the following terms or expressions are used with the meaning indicated:

UW

Unique Word

{with photonic or optical means}
Definition statement

This place covers:

This group covers clock synchronisation using at least one optical device that is essential for the functioning of the synchronizer. A synchronizer used in an optical transmission system but using exclusively electrical means for synchronization has to be classified in the other respective groups of H04L 7/00.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Non-linear optical devices

G02F 1/35

Computer systems or integrated circuits with clock distribution at least partially optical

G06F 1/105

Optical regenerators and retiming, e.g. 2R,3R

H04B 10/29

Optical TDM, alignment of optical frames and time slots

H04J 14/08

Synonyms and Keywords

In patent documents, the following abbreviations are often used:

NOLM

Non-linear Optical Loop Mirror

TOAD

Terahertz Optical Asymmetric Demultiplexer

{Receiver details}
Definition statement

This place covers:

Details in the construction of the synchronizer in the receiver, e.g. adaption of signals among various parts of the receiver; constructional details

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Details of RF receivers

H04B 1/0003, H04B 1/16

{taking measures against momentary loss of synchronisation, e.g. inhibiting the synchronisation, using idle words or using redundant clocks}
References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Introducing fill or idle bits into the data to maintain synchronization

H04L 2007/045

Error detection or correction of clock faults in computer systems

G06F 11/1604

PLL or DLL with redundancy

H03L 7/07

PLL or DLL with arrangements for protection against power supply fail

H03L 7/14

Fail safe clock arrangements in TDM equipment

H04J 3/0688

Special rules of classification

This class can be applied additionally to any other class in H04L 7/00

{Preprocessing of received signal for synchronisation, e.g. by code conversion, pulse generation or edge detection}
References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Synchronization by spectral filtering

H04L 7/027

{Transmitter details}
Definition statement

This place covers:

The transmitter is adapted to the synchronisation process, e.g. the receiver provides signalling concerning the synchronisation error to the transmitter.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Synchronization in computer networks, e.g. Time of Day

G06F 1/04

Buffers between clock domains

G06F 5/06; H04L 7/00

Speed or phase control by the received code signals, the signals containing no special synchronisation information {(H04L 7/0075 takes precedence)}
Definition statement

This place covers:

The error is based on the received code signal.

Synchronisation is achieved by intermediate buffering, multiple phases and/or intermediate clocks. Synchronisation of interfaces or among equipments having different clock phases or clock domains

References
Limiting references

This place does not cover:

with photonic or optical means

H04L 7/0075

Informative references

Attention is drawn to the following places, which may be of interest for search:

Synchronization based on transition of the received code signal

H04L 7/033

Using the properties of error detecting or error correcting codes

H04L 7/048

Computer systems with synchronization between clock domains

G06F 1/12

Computer systems with buffering between clock domains

G06F 5/06

Tuning resonant circuits

H03J

Bistable circuits with means to increase reliability, e.g. avoid metastability

H03K 3/0375

extracting the synchronising or clock signal from the received signal spectrum, e.g. by using a resonant or bandpass circuit
Definition statement

This place covers:

A spectral line at clock rate of NRZ data can be generated, e.g. by squaring or differentiating and subsequent filtering, e.g. SAW filter or FFT.

Covers detection of synchronization error by measuring a spectral property of a known code signal, e.g. UW or dotting.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Repeaters with retiming

H04L 25/242

Manipulating pulses with desired output intervals by the use of time reference signals, e.g. clock signals

H03K 5/135

Manipulating pulses by resonant circuits

H03K 5/145

Synonyms and Keywords

In patent documents, the following abbreviations are often used:

Dotting

Sequence of alternating pulses, e.g. 1010..

UW

Unique Word

using the transitions of the received signal to control the phase of the synchronising-signal-generating means, e.g. using a phase-locked loop
Definition statement

This place covers:

PLL with edge detectors, and at least partial analog loop elements, e.g. VCO;

Edge detectors like HOGGE type or ALEXANDER type.

The term "control" does not limit the scope to "tracking" or "closed loop" but includes also feed-forward control.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Measuring phase angle between a voltage and a current

G01R 25/00

Transition or edge detectors

H03K 5/1534

PLL or DLL

H03L 7/00

Special rules of classification

Initialization of the PLL is further classified in H04L 7/0004.

Special adaptions for preventing loss of synchronization or loss of lock are also classified in H04L 7/0083

{with a digital phase-locked loop [PLL] processing binary samples, e.g. add/subtract logic for correction of receiver clock (H04L 7/0337 takes precedence)}
Definition statement

This place covers:

This group also covers detection of the synchronization error by measuring the length of the received bits, e.g. by oversampling and sample processing of binary samples.

Covers correction of the synchronization error by add/subtract logic.

Digital implementation of DTTL.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Synchronization by integrate/dump

H04L 7/0332

Selection or interpolation among plural phase shifted clocks

H04L 7/0337

Comparing the phase or frequency

H03D 13/00

DPLL in general

H03L 7/099

Special rules of classification

H04L 7/0337 takes precedence

For the pulse length measurement is done by analogue means, e.g. integrate/dump, H04L 7/0332 takes precedence.

Synonyms and Keywords

In patent documents, the following abbreviations are often used:

PWD

Pulse Width Distortion

DTTL

Data Transition Tracking Loop

{with an integrator-detector}
Definition statement

This place covers:

Analogue techniques of determining the synchronization error by measuring a pulse length esp. for line codes with a transition in the bit cell like Manchester coding or NRZI.

Analogue implementation of DTTL.

References
Limiting references

This place does not cover:

Digital implementation of DTTL

H04L 7/0331

Informative references

Attention is drawn to the following places, which may be of interest for search:

Line coding

H04L 25/49

Glossary of terms

In this place, the following terms or expressions are used with the meaning indicated:

DTTL

Data Transition Tracking Loop

{Processing of samples having at least three levels, e.g. soft decisions}
Definition statement

This place covers:

Samples processed of more than binary values, if the processing evaluates a symbol transition.

First and also higher order derivatives of the sampled waveform, if a transition is detected.

Statistical analysis of the samples, e.g. histogram.

References
Limiting references

This place does not cover:

Synchronization by detection of decision error of samples

H04L 7/0062

Informative references

Attention is drawn to the following places, which may be of interest for search:

Demodulators

H04L 27/00

{Selecting between two or more discretely delayed clocks or selecting between two or more discretely delayed received code signals}
Definition statement

This place covers:

The selected phase is looped back into the phase error detection.

Comparison of the actually selected phase with a previously selected phase is not feed backward under this definition. Such a comparison functions as a filter, e.g. for reducing large phase jumps or jitter.

Phase aligners in switches of communication networks or packet receivers.

Phase aligners for electronic displays, e.g. DVI or HDMI interfaces, if the invention is not specially adapted to such a display, e.g. using special signals.

Synchronization by phase picking.

Covers also interpolation among different clock phases.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Computer interfaces or busses

G06F 13/40

Electronic displays

G09G

Synchronization in a TDM node

H04J 3/0685

Special rules of classification

Selection in an open loop control: H04L 7/0338 takes precedence.

Speed or phase control by synchronisation signals {(H04L 7/0075 takes precedence)}
Definition statement

This place covers:

Documents that only refer to the use of a synchronisation signal, e.g. UW, without further specifying their structure or the way it is detected.

Comma free codes.

Forbidden code words.

Relationships with other classification places

Synchronization signals in TDM frames: H04J 3/0602.

References
Limiting references

This place does not cover:

With photonic or optical means

H04L 7/0075

Informative references

Attention is drawn to the following places, which may be of interest for search:

Arrangements for synchronising receiver with transmitter

H04L 7/00

Synchronization information for carrier synchronization in demodulators

H04L 2027/0083

For changing the speed of data flow, i.e. speed regularizing

G06F 5/06

Special rules of classification

Special synchronisation signals, e.g. midambles or variable UW: H04L 7/041.

Synonyms and Keywords

In patent documents, the following abbreviations are often used:

Dotting

Alternating 1010... sequence or sequence of complex phase reversal, e.g. ABAB constellation points during training of a MODEM

UW

Unique Word as generic synonym for synchronisation data in the received signal.

{using special codes as synchronising signal}
Definition statement

This place covers:

Code construction.

Theory of codes used for synchronization.

Training sequences or midambles.

Variable Synchronization codes, e.g. according to synchronization state or for transmission of low rate data like signalling.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Training sequences for carrier synchronisation

H04L 2027/0093

Corresponding special codes for TDM frames

H04J 3/0605

{Detectors therefor, e.g. correlators, state machines (digital correlators in general G06F 17/15)}
Definition statement

This place covers:

Cross-correlation or auto-correlation.

Peak detection, threshold control at the output of the correlator.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Correlation computing

G06F 17/15

Detectors of FAW in TDM frames

H04J 3/0608

Selective call receivers

H04W 88/022

Special rules of classification

Windowing around expected location of the synchronization information, H04L 7/08 takes precedence.

Synchronization state machines or diagrams for acquisition, search, verify or lock, H04L 7/10 takes precedence.

Synonyms and Keywords

In patent documents, the following abbreviations are often used:

UW

Unique Word. This term is even used even if the bits of the synchronization information could occur in other places of the received data, e.g. mimic in the payload

{Pseudo-noise [PN] codes variable during transmission (synchronisation of spread spectrum receivers H04B 1/69)}
Definition statement

This place covers:

PN codes used for synchronisation, if the PN synchronisation signals is varying during transmission, e.g. by a feedback shift-register. Fixed synchronisation signals, e.g. unique words, FAW signals, are not to be classified in this group. This also applies even if the synchronisation signal can be presented as a state of such a PN-code generator. Only if the generator is active and shifts, then the document is classified here.

References
Limiting references

This place does not cover:

Scrambling

H04L 25/03866

Synchronisation of Spread Spectrum receivers

H04B 1/69

PN codes for synchronization of TDM frames

H04J 3/0611

Glossary of terms

In this place, the following terms or expressions are used with the meaning indicated:

PN code

Pseudo-Noise or pseudorandom code

FAW

Frame Alignment Word

{using a single bit, e.g. start stop bit}
Definition statement

This place covers:

Synchronization by using a start bit or start/stop bit, incl. the use of the transition of the stop bit to the adjacent start bit.

Covers single synch pulses with differing length from information pulse length.

References
Limiting references

This place does not cover:

Two or more pulses with differing length compared to the length of the data bits

H04L 7/06

Informative references

Attention is drawn to the following places, which may be of interest for search:

Start/Stop transmission in general

H04L 25/38

{using a dotting sequence}
Definition statement

This place covers:

Complex phase reversals used for symbol synchronization in digital demodulators.

References
Limiting references

This place does not cover:

Transmission of a dotting sequence without further transmission of user data is a transmission of a clock signal

H04L 7/0008

Informative references

Attention is drawn to the following places, which may be of interest for search:

Detection of dotting by spectral analysis, e.g. filter around basic frequency

H04L 7/027

If the dotting is degraded at the receiver to a sinus

H04L 2007/047

Digital demodulators

H04L 27/00

Glossary of terms

In this place, the following terms or expressions are used with the meaning indicated:

Dotting sequence

Alternating sequence, e.g. 1010... , 01010, ABAB

{using the properties of error detecting or error correcting codes, e.g. parity as synchronisation signal}
Definition statement

This place covers:

Use of Error Correcting or detecting codes for alignment of packets or ATM cells.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Error Detection or correction codes in general, e.g. ECC or FEC

H04L 1/00

Synchronisation based on error coding or decoding or code conversion

H03M 13/33

Glossary of terms

In this place, the following terms or expressions are used with the meaning indicated:

ATM

Asynchronous Transfer Mode

the synchronisation signals differing from the information signals in amplitude, polarity or frequency {or length}
Definition statement

This place covers:

H04L as such is directed to transmission of digital signals, meaninig the information is transmitted in binary form. Synchronisation signals classified here have a different form than the information signal, e.g. a higher amplitude, a longer pulse width.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Detection the differing parameter based on the coding rule

H04L 7/0066

Detection of the differing length by a digital means

H04L 7/0331

Single pulse for synchronization

H04L 7/044

Line codes and detectors therefore

H04L 25/49

{and superimposed by modulation}
Definition statement

This place covers:

Synchronisation information is not transmitted in series with the information signals, i.e. as this is the case for packet headers. Instead, a synchronisation signal is provided by modulation of the information signal, e.g. by an amplitude modulation using a low modulation index

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Amplitude modulation of the synchronization information

H04J 7/00

The synchronization information is multiplexed as a differing type of modulation

H04J 9/00

the synchronisation signals recurring cyclically
Definition statement

This place covers:

Detection by windowing around the expected recurring location of the synchronization information.

References
Limiting references

This place does not cover:

Frame synchronization of TDM frames

H04J 3/0602

Arrangements for initial synchronisation
Definition statement

This place covers:

Variable synchronization information for initialisation.

During initialisation, variable means of the detector, e.g. low detection threshold and increasing threshold when synchronisation information is detected.

Signalling or handshaking for initialisation.

References
Limiting references

This place does not cover:

Details of the phase-locked loop for assuring initial synchronisation

H03L 7/10

Special rules of classification

Other means for synchronisation, H04L 7/0004 takes precedence.

Start/Stop bit detection, H04L 7/044 takes precedence.

Dotting detection, H04L 7/046 takes precedence.

{Cryptographic mechanisms or cryptographic} arrangements for secret or secure communications; Network security protocols
Definition statement

This place covers:

Cryptographic mechanisms including cryptographic protocols and cryptographic algorithms, whereby a cryptographic protocol is a distributed cryptographic algorithm defined by a sequence of steps precisely specifying the actions required of two or more entities to achieve specific security objectives (e.g. cryptographic protocol for key agreement), and whereby a cryptographic algorithm is specifying the steps followed by a single entity to achieve specific security objectives (e.g. cryptographic algorithm for symmetric key encryption).

H04L 9/00 focuses on cryptographic mechanisms such as encryption schemes, digital signatures, hash functions, random number generation, key management, said cryptographic mechanisms providing information security such as privacy or confidentiality, data integrity, message authentication, entity authentication, authorization, validation, certification, time-stamping.

H04L 9/00 covers also Financial cryptography.

H04L 9/00 covers also countermeasures against attacks on cryptographic mechanisms.

Relationships with other classification places

H04L 63/00 Networking architectures and network communication protocols for securing the traffic flowing through data packet networks and providing secure exchanges among applications communicating through data packet networks.

H04L 63/00 covers specifically network architectures and network communication protocols for supporting:

  • filtering (e.g. transferring, blocking, dropping) traffic according to security rules;
  • authenticating and authorizing the entities sending and/or receiving the traffic;
  • protecting the data packets against unauthorized reading or modification;
  • detecting intruders and preventing the transmission of unauthorized, malicious or forged packets;
  • lawful interception for legally authorised parties to access protected information.

H04L 63/00 focuses on network architectures (i.e. network entities involved, roles played by these entities) and network communication protocols (i.e. how these network entities communicate) regardless of the specifics of the cryptographic mechanism used.

G06F 21/00 Security arrangements for protecting computers or computer systems against unauthorised activity, where the cryptographic mechanisms are not relevant.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Network architectures or network communication protocols for network security

H04L 63/00

Pseudo-random number generators (if not intended for cryptographic purposes)

G06F 7/584

Finite field arithmetic over elliptic curve (if not intended for cryptographic purposes)

G06F 7/725

Protection against unauthorized use of memory

G06F 12/14

Security arrangements for protecting computers, components thereof, programs or data against unauthorised activity

G06F 21/00

Character or pattern recognition

G06K 9/00

Payments on Internet

G06Q 20/00

Smarts-cards

G07F 7/10

Coding or ciphering apparatuses for cryptographic or other purposes involving the need for secrecy

G09C

Circuits for prevention of unauthorised reproduction

G11B 20/00086

Aspects related to secret communication for (analogue) speech signals

H04K 1/00

Secrecy systems for scanning, transmission or reproduction of documents

H04N 1/44

Subscription TV encryption

H04N 7/167

Content distribution

H04N 21/00

Network architectures or network communication protocols for wireless network security

H04W 12/00

Special rules of classification

The classification of additional information is not seen as mandatory; it will be up to the classifier to decide whether the additional information should be classified or not (is pertinent or not). If considered pertinent, it should be classified.

Indexing Codes are to be used as orthogonal cross.

Invention may be assign more than one code if necessary.

Synonyms and Keywords

In patent documents, the following abbreviations are often used:

MAC

Message authentication code

DPA

Differential power analysis

SPA

Simple power analysis

PRNG

Pseudo random number generator

PKI

Public key infrastructure

KDC

Key distribution server

TTP

Trusted third party

CA

Certificate authority

IBE

Identity based encryption

DH

Diffie-Hellman

QKD

Quantum key distribution

TPM

Trusted platform module

PUF

Physically unclonable function

CRL

Certificate revocation list

In patent documents, the following words/expressions are often used as synonyms:

  • "encryption" and "ciphering"
{Countermeasures against attacks on cryptographic mechanisms (network architectures or network communication protocols for protection against malicious traffic H04L 63/1441)}
Definition statement

This place covers:

Subject-matter directed to protection and enhancement of cryptographic mechanisms against cryptographic attacks as replay, brute force or birthday attacks.

References
Limiting references

This place does not cover:

Network architectures or network communication protocols for protection against malicious traffic

H04L 63/1441

{involving public key infrastructure [PKI] trust models (network architecture or network communication protocol for supporting authentication of entities using certificates in a packet data network H04L 63/0823)}
Definition statement

This place covers:

Subject-matter directed to authentication infrastructures based on public-key cryptography.

References
Limiting references

This place does not cover:

Network architecture or network communication protocol for supporting authentication of entities using certificates in a packet data network

H04L 63/0823

{involving homomorphic encryption}
Definition statement

This place covers:

Subject-matter directed to homomorphic cryptographic mechanisms.

the encryption apparatus using shift registers or memories for block-wise {or stream} coding, e.g. DES systems {or RC4; Hash functions; Pseudorandom sequence generators}
Definition statement

This place covers:

Subject-matter directed to symmetric-key encryption as DES, (i.e. same keys are used for encryption and decryption), hash functions as MD5, stream ciphers as RC4 or pseudorandom sequence generation.

{Block ciphers, i.e. encrypting groups of characters of a plain text message using fixed encryption transformation}
Definition statement

This place covers:

Encrypting groups of characters of a plain text message using a fixed encryption transformation.

{with splitting of the data block into left and right halves, e.g. Feistel based algorithms, DES, FEAL, IDEA or KASUMI}
Definition statement

This place covers:

Subject-matter directed to cryptographic mechanisms as Feistel based algorithms, DES, FEAL, IDEA or KASUMI algorithms.

{Substitution permutation network [SPN], i.e. cipher composed of a number of stages or rounds each involving linear and nonlinear transformations, e.g. AES algorithms}
Definition statement

This place covers:

Ciphers composed of a number of stages/rounds each involving linear or nonlinear transformations, as AES algorithm.

{Modes of operation, e.g. cipher block chaining [CBC], electronic codebook [ECB] or Galois/counter mode [GCM]}
Definition statement

This place covers:

Subject-matter directed to modes of operation for block ciphers, as CBC (cipher block chaining), CFB (cipher feedback) or OFB (output feedback).

{Hash functions, e.g. MD5, SHA, HMAC or f9 MAC}
Definition statement

This place covers:

The design, structure or function of cryptographic hash functions, as message authentication codes (MAC) or modification detection codes (MDC).

{Encryption by serially and continuously modifying data stream elements, e.g. stream cipher systems, RC4, SEAL or A5/3}
Definition statement

This place covers:

Subject-matter directed to synchronous or asynchronous stream ciphers (i.e. encrypting individual characters of a plaintext message one at a time, using an encryption transformation which varies with time), and to key-stream generation.

{Pseudorandom key sequence combined element-for-element with data sequence, e.g. one-time-pad [OTP] or Vernam's cipher}
Definition statement

This place covers:

Subject-matter directed to encryption (combination) of data with (pseudo)random key-stream.

{with particular pseudorandom sequence generator}
Definition statement

This place covers:

Subject-matter directed to the design, structure, functionality or mechanism of pseudorandom sequence generators.

{producing a non-linear pseudorandom sequence}
Definition statement

This place covers:

Subject-matter directed to the design, structure, functionality or mechanism of pseudorandom sequence generators using non-linear functions.

Key distribution {or management, e.g. generation, sharing or updating, of cryptographic keys or passwords (network architectures or network communication protocols for supporting key management in a packet data network H04L 63/06)}
Definition statement

This place covers:

Subject-matter directed to management of secret material including generation, distribution, sharing, updating of cryptographic keys or passwords.

References
Limiting references

This place does not cover:

Network architectures or network communication protocols for supporting key management in a packet data network

H04L 63/06

{Key establishment, i.e. cryptographic processes or cryptographic protocols whereby a shared secret becomes available to two or more parties, for subsequent use}
Definition statement

This place covers:

Subject-matter directed to processes or cryptographic protocols whereby a secret (as cryptographic key, password) becomes available to two or more parties, for subsequent cryptographic use.

{Key transport or distribution, i.e. key establishment techniques where one party creates or otherwise obtains a secret value, and securely transfers it to the other(s) (network architectures or network communication protocols for key distribution in a packet data network H04L 63/062)}
Definition statement

This place covers:

Subject-matter directed to key establishment techniques where one party creates or otherwise obtains a secret value, and securely transfers it to other(s).

References
Limiting references

This place does not cover:

Network architectures or network communication protocols for key distribution in a packet data network

H04L 63/062

{using key encryption key}
Definition statement

This place covers:

Subject-matter directed to managing (e.g. transport, distribute) cryptographic keys for securing information by using key encryption keys. Before transmission/distribution the cryptographic keys are encrypted with the key encryption keys. Passwords may be also used as cryptographic keys for encryption.

{using asymmetric-key encryption or public key infrastructure [PKI], e.g. key signature or public key certificates}
Definition statement

This place covers:

Subject-matter directed to managing (e.g. transport, distribute) cryptographic keys for securing information by using public key encryption. The cryptographic key is either encrypted with a private key (i.e. signature) and decrypted with the corresponding public key, or it is encrypted with a public key and decrypted with the corresponding private key. A public key infrastructure (PKI) may be also used wherein the public keys are certified.

{involving distinctive intermediate devices or communication paths (network architectures or network communication protocols using different networks H04L 63/18)}
Definition statement

This place covers:

Subject-matter directed to exchanging/distributing cryptographic keys between communication partners by using distinctive intermediate devices or communication paths/channels. The paths/channels may be out-of-band channels or virtual paths.

References
Limiting references

This place does not cover:

Network architectures or network communication protocols using different networks

H04L 63/18

{involving central third party, e.g. key distribution center [KDC] or trusted third party [TTP]}
Definition statement

This place covers:

Subject-matter directed to centralized key units as key distribution center (KDC), trusted third party (TTP) or key translation center (KTC) that are used for cryptographic key management.

Examples: "Handbook of Applied Cryptography" by A.J. Menezes, P.C. van Oorschot, S. A. Vanstone, 5th Edition, June 2001, Pages 546-549.

{involving conference or group key (network architectures or network communication protocols for key management in group communication in a packet data network H04L 63/065)}
Definition statement

This place covers:

Subject-matter directed to secure mechanisms for distributing cryptographic group keys to different communication entities. To ensure the security of a multi-party communication, the multi-party communication messages are transmitted in encrypted form. The group key used for encrypting and decrypting the multi-party communication messages are only known to the group members, so as to ensure that the encrypted messages may be interpreted only by the group members.

References
Limiting references

This place does not cover:

Network architectures or network communication protocols for key management in group communication in a packet data network

H04L 63/065

{using tree structure or hierarchical structure}
Definition statement

This place covers:

Subject-matter directed to mechanisms for distributing cryptographic conference or group keys to different communication entities involving tree or hierarchical structures wherein the central key unit is the root and the group members are the leafs.

{Key agreement, i.e. key establishment technique in which a shared key is derived by parties as a function of information contributed by, or associated with, each of these (network architectures or network communication protocols for key exchange in a packet data network H04L 63/061)}
Definition statement

This place covers:

Subject-matter directed to key establishment techniques in which a shared key is derived by parties as a function of information contributed by, or associated with, each of these, ideally such that no party can predetermine the resulting value.

References
Limiting references

This place does not cover:

Network architectures or network communication protocols for key exchange in a packet data network

H04L 63/061

{involving Diffie-Hellman or related key agreement protocols}
Definition statement

This place covers:

Subject-matter directed to key agreement protocols that allow users or entities to exchange public key values and from these values and knowledge of their own corresponding private keys, securely compute a shared key, allowing for further secure communication.

Examples: "Handbook of Applied Cryptography" by A.J. Menezes, P.C. van Oorschot, S. A. Vanstone, 5th Edition, June 2001, Pages 515-516.

{with user authentication or key authentication, e.g. ElGamal, MTI, MQV-Menezes-Qu-Vanstone protocol or Diffie-Hellman protocols using implicitly-certified keys}
Definition statement

This place covers:

Subject-matter directed to key agreement protocols providing user authentication or key authentication, to schemes as ElGamal, MTI, MQV or related protocols, to key agreement protocols using implicitly-certified keys, or to password-authenticated key agreement mechanisms as PAKE (password-authenticated key exchange), EKE (encrypted key exchange) or SPEKE (simple password exponential key exchange).

Examples: "Handbook of Applied Cryptography" by A.J. Menezes, P.C. van Oorschot, S. A. Vanstone, 5th Edition, June 2001, Pages 517-523.

{involving identity based encryption [IBE] schemes}
Definition statement

This place covers:

Subject-matter directed to key agreement protocols involving IBE schemes (the public key of a user is the binary sequence corresponding to information identifying him in a non-ambiguous way).

Examples: "Handbook of Applied Cryptography" by A.J. Menezes, P.C. van Oorschot, S. A. Vanstone, 5th Edition, June 2001, Pages 561-562.

{Secret sharing or secret splitting, e.g. threshold schemes}
Definition statement

This place covers:

Subject-matter directed to distribution of a secret amongst a group of participants, each of which is allocated a share of the secret; the secret can be reconstructed only when a sufficient number of shares are combined together; individual shares are of no use on their own (threshold schemes).

{Quantum cryptography (transmission systems employing electromagnetic waves other than radio waves, e.g. light, infra-red H04B 10/00; wavelength-division multiplex systems H04J 14/02)}
Definition statement

This place covers:

Subject-matter directed to quantum key distribution (QKD), i.e. the process of using quantum communication to establish a shared key between two parties without a third party learning anything about that key, even if said third party can eavesdrop on all communication between said two parties.

References
Limiting references

This place does not cover:

Transmission systems employing electromagnetic waves other than radio-waves

H04B 10/00

Wavelength-division multiplex systems

H04J 14/02

{involving additional nodes, e.g. quantum relays, repeaters, intermediate nodes or remote nodes}
Definition statement

This place covers:

Subject-matter directed to QKD involving additional nodes as quantum relays, repeaters, intermediate or remote nodes.

{Details about key distillation or coding, e.g. reconciliation, error correction, privacy amplification, polarisation coding or phase coding}
Definition statement

This place covers:

Subject-matter directed to reconciliation, error correction, privacy amplification, polarisation or phase coding for QKD systems.

{Generation of secret information including derivation or calculation of cryptographic keys or passwords}
Definition statement

This place covers:

Subject-matter directed to generation, derivation, calculation or extraction of cryptographic keys or passwords.

{involving passwords or one-time passwords (network architectures or network communication protocols for using one-time keys in a packet data network H04L 63/067)}
Definition statement

This place covers:

Subject-matter directed to derivation or generation of encryption keys from passwords.

References
Limiting references

This place does not cover:

Network architectures or network communication protocols for using one-time keys in a packet data network

H04L 63/067

{involving user or device identifiers, e.g. serial number, physical or biometrical information, DNA, hand-signature or measurable physical characteristics}
Definition statement

This place covers:

Subject-matter directed to cryptographic key derivation or extraction involving user or device identifiers as serial number of a device, measurable physical characteristics provided by a device like a PUF (physical unclonable function), or biometrical information of a user.

{involving random numbers or seeds}
Definition statement

This place covers:

Subject-matter directed to cryptographic mechanisms for cryptographic keys generation involving random numbers or seeds.

{using geo-location information, e.g. location data, time, relative position or proximity to other entities}
Definition statement

This place covers:

Subject-matter directed to cryptographic key derivation/generation using data regarding geographical position, time, relative or proximity position to other entities.

{based on channel impulse response [CIR]}
Definition statement

This place covers:

Subject-matter directed to mechanisms for cryptographic key generation / derivation using channel characteristics.

{using additional device, e.g. trusted platform module [TPM], smartcard, USB or hardware security module [HSM]}
Definition statement

This place covers:

Subject-matter directed to cryptographic keys generation using secure crypto-processors as trusted platform modules, smartcards or hardware security modules.

{Usage controlling of secret information, e.g. techniques for restricting cryptographic keys to pre-authorized uses, different access levels, validity of crypto-period, different key- or password length, or different strong and weak cryptographic algorithms (network architectures or network communication protocols for using time-dependent keys in a packet data network H04L 63/068)}
Definition statement

This place covers:

Subject-matter relating to cryptographic techniques (as control vectors, key notarization) for restricting cryptographic keys to pre-authorized uses, to crypto-periods of keys (long-term, short-term, ephemeral keys), or to controlling encryption strength (export regulation for cryptographic algorithms).

References
Limiting references

This place does not cover:

Network architectures or network communication protocols for using time-dependent keys in a packet data network

H04L 63/068

{Revocation or update of secret information, e.g. encryption key update or rekeying}
Definition statement

This place covers:

Subject-matter relating to cryptographic keys revocation (compromised keys have to be revoked) or updating (old key is replaced by new key).

{Escrow, recovery or storing of secret information, e.g. secret key escrow or cryptographic key storage}
Definition statement

This place covers:

Subject-matter directed to cryptographic mechanisms for secret key escrow (user traffic is encrypted such that the session keys used for the encryption are available to properly authorized third parties under special circumstances), for secret key recovery (encrypted data have to be recovered following loss or destruction of keying material due to equipment failure or malicious activities), or for storing/restoring of secret keys (as backups).

{involving additional devices, e.g. trusted platform module [TPM], smartcard or USB}
Definition statement

This place covers:

Subject-matter directed to involving additional (portable) units (as TPM, smartcards) in the cryptographic mechanisms for escrow, recovery or storing of secret information.

using a plurality of keys or algorithms {(network architectures or network communication protocols wherein the sending and receiving network entities apply hybrid encryption, i.e. combination of symmetric and asymmetric encryption H04L 63/045)}
Definition statement

This place covers:

Subject-matter directed to cryptographic mechanisms using a plurality of keys or algorithms (as hybrid encryption, i.e. combination of symmetric and public-key encryption) for providing information security.

References
Limiting references

This place does not cover:

Network architectures or network communication protocols wherein the sending and receiving network entities apply hybrid encryption, i.e. combination of symmetric and asymmetric encryption

H04L 63/045

the keys or algorithms being changed during operation
Definition statement

This place covers:

Subject-matter directed to cryptographic mechanisms using a plurality of keys or algorithms changing dynamically or during operation.

Public key, i.e. encryption algorithm being computationally infeasible to invert or user's encryption keys not requiring secrecy
Definition statement

This place covers:

Subject-matter directed to asymmetric-key or public key cryptography.

{underlying computational problems or public-key parameters}
Definition statement

This place covers:

Subject-matter directed to the interaction between the intractability of several computational problems (as the quadratic residuosity problem) and the security of public-key cryptosystems, or to details relating to public-key parameters (as generators and elements of high order).

{involving the discrete logarithm problem, e.g. ElGamal or Diffie-Hellman systems}
Definition statement

This place covers:

Subject-matter directed to public-key schemes based on the discrete logarithm problem.

{involving the integer factorization problem, e.g. RSA or quadratic sieve [QS] schemes}
Definition statement

This place covers:

Subject-matter directed to public-key schemes based on the integer factorization problem.

{details relating to polynomials generation, e.g. generation of irreducible polynomials}
Definition statement

This place covers:

Subject-matter directed to polynomials generation in public-key schemes.

{details relating to pseudo-prime or prime number generation, e.g. primality test}
Definition statement

This place covers:

Subject-matter directed to pseudo-prime or prime number generation in public-key schemes.

{based on error correction codes, e.g. McEliece}
Definition statement

This place covers:

Subject-matter directed to public-key schemes involving error correction codes.

{involving algebraic varieties, e.g. elliptic or hyper-elliptic curves}
Definition statement

This place covers:

Subject-matter directed to details of the algebraic or abelian varieties used in the public-key cryptographic schemes, as algebraic groups, rings, fields or elliptic curves.

{involving pairings, e.g. identity based encryption [IBE], bilinear mappings or bilinear pairings, e.g. Weil or Tate pairing}
Definition statement

This place covers:

Subject-matter directed to public-key schemes involving pairings or mappings, as identity based encryption (IBE) schemes.

{involving Lattices or polynomial equations, e.g. NTRU scheme}
Definition statement

This place covers:

Subject-matter directed to public-key schemes involving Lattices (e.g. vector spaces) or polynomial equations.

including means for verifying the identity or authority of a user of the system {or for message authentication, e.g. authorization, entity authentication, data integrity or data verification, non-repudiation, key authentication or verification of credentials} ({network architectures or network communication protocols for supporting entities authentication in a packet data network H04L 63/08; applying verification of the received information H04L 63/12; } computer systems G06F; coin-freed or like apparatus with coded identity card or credit card G07F 7/08)
Definition statement

This place covers:

Subject-matter directed to cryptographic mechanisms for authentication or identification, including mechanisms (involving cryptographic primitives or data structures as signatures, certificates, credentials) for authorization, entity authentication, message authentication, data integrity, key authentication, non-repudiation, verification or proof of knowledge.

References
Limiting references

This place does not cover:

Network architectures or network communication protocols for supporting entities authentication in a packet data network

H04L 63/08

Network architectures or network communication protocols applying verification of the received information

H04L 63/12

Electrical digital data processing

G06F

by coded identity card or credit card

G07F 7/08

{involving a third party or a trusted authority}
Definition statement

This place covers:

Subject-matter directed to cryptographic mechanisms for authentication between two devices involving a third device.

{using tickets or tokens, e.g. Kerberos (network architectures or network communication protocols for entities authentication using tickets in a packet data network H04L 63/0807)}
Definition statement

This place covers:

Subject-matter directed to cryptographic mechanisms for authentication using tickets or tokens (as Kerberos authentication protocols).

Examples: "Handbook of Applied Cryptography" by A.J. Menezes, P.C. van Oorschot, S. A. Vanstone, 5th Edition, June 2001, Pages 501-502.

References
Limiting references

This place does not cover:

Network architectures or network communication protocols for entities authentication using tickets in a packet data network

H04L 63/0807

{using a plurality of channels (network architectures or network communication protocols using different networks H04L 63/18)}
Definition statement

This place covers:

Subject-matter directed to authentication involving the use of a plurality of channels, as for example the use of a wire channel and a wireless channel.

References
Limiting references

This place does not cover:

Network architectures or network communication protocols using different networks

H04L 63/18

{using proof of knowledge, e.g. Fiat-Shamir, GQ, Schnorr, ornon-interactive zero-knowledge proofs}
Definition statement

This place covers:

Subject-matter directed to identification mechanisms using knowledge proofs, as (NIZKP) non-interactive zero-knowledge proofs (Fiat-Shamir, Schnorr protocols).

{interactive zero-knowledge proofs}
Definition statement

This place covers:

Subject-matter directed to identification mechanisms using interactive zero-knowledge proofs.

{using a predetermined code, e.g. password, passphrase or PIN (network architectures or network communication protocols for supporting authentication of entities using passwords in a packet data network H04L 63/083)}
Definition statement

This place covers:

Subject-matter directed to cryptographic mechanisms for authentication or authorization using predetermined codes as passwords, passphrases, personal identification numbers (PIN).

References
Limiting references

This place does not cover:

Network architectures or network communication protocols for supporting authentication of entities using passwords in a packet data network

H04L 63/083

{One-time or temporary data, i.e. information which is sent for every authentication or authorization, e.g. one-time-password, one-time-token or one-time-key}
Definition statement

This place covers:

Subject-matter directed to authentication or authorization using predetermined codes, said predetermined codes comprising information which is sent for every authentication or authorization, as one-time-password, one-time-token or one-time-key.

{Biological data, e.g. fingerprint, voice or retina (network architectures or network communication protocols for supporting authentication of entities using biometrical features in a packet data network H04L 63/0861)}
Definition statement

This place covers:

Subject-matter directed to cryptographic mechanisms for identification or verification of an individual using biometrical data as fingerprint, voice or retina.

References
Limiting references

This place does not cover:

Network architectures or network communication protocols for supporting authentication of entities using biometrical features in a packet data network

H04L 63/0861

{involving additional secure or trusted devices, e.g. TPM, smartcard, USB or software token (network architectures or network communication protocols for supporting authentication of entities using an additional device in a packet data network H04L 63/0853)}
Definition statement

This place covers:

Subject-matter directed to cryptographic mechanisms for authentication or authorization involving hardware tokens like trusted platform module (TPM), smartcard, USB or software tokens.

References
Limiting references

This place does not cover:

Network architectures or network communication protocols for supporting authentication of entities using an additional device in a packet data network

H04L 63/0853

{using cryptographic hash functions}
Definition statement

This place covers:

Subject-matter directed to authentication mechanisms using cryptographic hash functions.

{involving non-keyed hash functions, e.g. modification detection codes [MDCs], MD5, SHA or RIPEMD}
Definition statement

This place covers:

Subject-matter directed to authentication mechanisms involving modification detection codes (MDC's) as MD5, SHA or RIPEMD, also called non-keyed hash functions.

{involving keyed hash functions, e.g. message authentication codes [MACs], CBC-MAC or HMAC}
Definition statement

This place covers:

Subject-matter directed to authentication mechanisms involving message authentication codes (MAC's) as CBC-MAC or HMAC, also called keyed hash functions.

{involving digital signatures}
Definition statement

This place covers:

Subject-matter directed to authentication mechanisms involving digital signatures.

{using RSA or related signature schemes, e.g. Rabin scheme}
Definition statement

This place covers:

Subject-matter directed to authentication mechanisms involving RSA or related signature schemes, as the Rabin signature scheme.

Examples: "Handbook of Applied Cryptography" by A.J. Menezes, P.C. van Oorschot, S. A. Vanstone, 5th Edition, June 2001, Pages 433-447.

{using DSA or related signature schemes, e.g. elliptic based signatures, ElGamal or Schnorr schemes}
Definition statement

This place covers:

Subject-matter directed to authentication mechanisms involving DSA or related signature schemes, as elliptic curve digital signature algorithm ECDSA or ElGamal signature scheme.

Examples: "Handbook of Applied Cryptography" by A.J. Menezes, P.C. van Oorschot, S. A. Vanstone, 5th Edition, June 2001, Pages 452-462.

{using group based signatures, e.g. ring or threshold signatures}
Definition statement

This place covers:

Subject-matter directed to authentication mechanisms using digital signatures where signers can establish groups such that each member of the group can produce signatures anonymously on behalf of the group.

{using blind signatures}
Definition statement

This place covers:

Subject-matter directed to authentication mechanisms using signatures schemes in which the content of a message is disguised before it is signed.

Examples: "Handbook of Applied Cryptography" by A.J. Menezes, P.C. van Oorschot, S. A. Vanstone, 5th Edition, June 2001, Page 475.

{involving certificates, e.g. public key certificate [PKC] or attribute certificate [AC]; Public key infrastructure [PKI] arrangements (network architectures or network communication protocols for supporting authentication of entities using certificates in a packet data network H04L 63/0823)}
Definition statement

This place covers:

Subject-matter directed to cryptographic mechanisms involving digital certificates as public key certificates or attribute certificates, or to public key infrastructure (PKI) based authentication/verification using certificates.

Examples: "Handbook of Applied Cryptography" by A.J. Menezes, P.C. van Oorschot, S. A. Vanstone, 5th Edition, June 2001, Pages 559-561.

References
Limiting references

This place does not cover:

Network architectures or network communication protocols for supporting authentication of entities using certificates in a packet data network

H04L 63/0823

{using certificate chains, trees or paths; Hierarchical trust model}
Definition statement

This place covers:

Subject-matter directed to authentication mechanisms involving multiple certification authorities (CA) in public-key systems. Trust relationships between the CA's determine how certificates issued by one CA may be utilized or verified by entities certified by distinct CA's. Hierarchical trust models for certification and cross-certificates are also covered by this subgroup.

Examples: "Handbook of Applied Cryptography" by A.J. Menezes, P.C. van Oorschot, S. A. Vanstone, 5th Edition, June 2001, Pages 572-575.

{using certificate validation, registration, distribution or revocation, e.g. certificate revocation list [CRL]}
Definition statement

This place covers:

Subject-matter directed to cryptographic mechanisms involving certificate generation, validation, registration, distribution (pull, push model) or revocation (certificate revocation list CRL).

Examples: "Handbook of Applied Cryptography" by A.J. Menezes, P.C. van Oorschot, S. A. Vanstone, 5th Edition, June 2001, Pages 576-577.

{using challenge-response}
Definition statement

This place covers:

Subject-matter directed to cryptographic mechanisms comprising protocols where a verifier sends a claimant a challenge (usually a random value or a nonce) that the claimant combines with a shared secret (often by hashing the challenge and secret together) to generate a response that is sent to the verifier. The verifier knows the shared secret and can independently compute the response and compare it with the response generated by the claimant.

Examples: "Handbook of Applied Cryptography" by A.J. Menezes, P.C. van Oorschot, S. A. Vanstone, 5th Edition, June 2001, Pages 397-405.

{for mutual authentication (network architectures or network communication protocols for achieving mutual authentication in a packet data network H04L 63/0869)}
Definition statement

This place covers:

Subject-matter directed to authentication between parties that may corroborate their identities to the other.

References
Limiting references

This place does not cover:

Network architectures or network communication protocols for achieving mutual authentication in a packet data network

H04L 63/0869

{using physically unclonable functions [PUF]}
Definition statement

This place covers:

Subject-matter directed to authentication using PUF.

{involving time stamps, e.g. generation of time stamps}
Definition statement

This place covers:

Subject-matter directed to cryptographic mechanisms for authentication involving time stamps or generation of timestamps.

Examples: "Handbook of Applied Cryptography" by A.J. Menezes, P.C. van Oorschot, S. A. Vanstone, 5th Edition, June 2001, Pages 581-583.

Bits, or blocks of bits, of the telegraphic message being interchanged in time {(for speech signals H04K 1/06)}
Definition statement

This place covers:

Subject-matter directed to cryptographic mechanisms involving interchanging in time bits or block of bits of the message.

References
Limiting references

This place does not cover:

by transmitting the information of elements thereof at unnatural speeds or in jumbled order or backwards

H04K 1/06

with means for detecting characters not meant for transmission
Definition statement

This place covers:

Subject-matter directed to cryptographic mechanisms involving means for detecting characters not meant for transmission.

Encryption being effected by mechanical apparatus, e.g. rotating cams, switches, keytape punchers
Definition statement

This place covers:

Subject-matter directed to cryptographic mechanisms involving encryption effected by mechanical apparatus, as rotating cams, switches or key-tape punchers.

Data switching networks (interconnection of, or transfer of information or other signals between, memories, input/output devices or central processing units G06F 13/00)
Definition statement

This place covers:

Transfer of information having been supplied in digital form in data switching networks, e.g.

Systems characterised by network topology;

Systems in which paths are physically permanent during the communication, e.g. connection oriented communication, virtual circuits;

Systems in which the path identification data is included in each information unit, e.g. connectionless communication, datagram;

Hybrid switching systems;

Arrangements for connecting networks having different types of switching systems;

Topology management and discovery;

Local area networks and interworking arrangements there between;

Flow control and congestion control. Traffic scheduling and balancing;

Routing, pathfinding;

Access control and network resource allocation;

Asynchronous transfer mode networks.

References
Limiting references

This place does not cover:

Interconnection of, or transfer of information or other signals between, memories, input/output devices or central processing units

G06F 13/00

Interprocessor communication using networks

G06F 15/173

Informative references

Attention is drawn to the following places, which may be of interest for search:

Cryptographic protocols

H04L 9/00

Network security protocols

H04L 63/00

Protocols for real-time services in data packet switching networks

H04L 65/00

Real-time session management in data packet switching networks

H04L 65/1066

Network protocols for data switching network services

H04L 67/00

Session management in data packet switching networks

H04L 67/14

Computer-aided management of electronic mail

G06Q 10/10

Multiplexing systems in general

H04J

Automatic or semi-automatic exchanges

H04M 3/00

Telephony conferences arrangements

H04M 3/56

Manual exchanges

H04M 5/00

Conferences, e.g. video conferences

H04N 7/15

Selecting equipment

H04Q

Glossary of terms

In this place, the following terms or expressions are used with the meaning indicated:

Circuit switching

A system in which a communication path is physically permanent during the communication

Packet switching

A system in which information is divided into discrete data units, characterised by a data payload and an address part known as a header part. The data units are able to travel over different communication paths to the destination

Message switching systems

A system in which a message is sent into a network with the address of its destination added and it is routed to its destination through the network, e.g. electronic mail network systems

Hybrid switching

Combinations of different switching systems (e.g. packet switching systems and circuit switching systems)

Gateway

Arrangements for connecting between networks having different types of switching systems

Synonyms and Keywords

In patent documents, the following words/expressions are often used as synonyms:

  • "packet", "cell" and "frame"
Switchboards
Definition statement

This place covers:

Devices for a human operator manually and/or physically routing or switching communications between source and destination.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Routing or path finding of packets in data switching networks

H04L 45/00

Current supply arrangements
Definition statement

This place covers:

  • Usage of an independent power supply network
  • Extracting power from the data signal in the line
  • Power-over-Ethernet technologies (PoE, PoE+, PoE plus, IEEE 802.2af, IEEE 802.3at)

This groups contains documents dealing with different ways to supply power to terminals connected to a network.

References
Limiting references

This place does not cover:

Internal power supply in a computer

G06F 1/26

Transmission of data over power lines

H04B 3/54

Current supply to telephones

H04M 19/08

Informative references

Attention is drawn to the following places, which may be of interest for search:

Details regarding the feeding of energy to the node from the bus

H04L 12/40045

Glossary of terms

In this place, the following terms or expressions are used with the meaning indicated:

PoE

Power-over-Ethernet

PSE

Power Sourcing Equipment

PD

Powered Device

Arrangements for remote connection or disconnection of substations or of equipment thereof
Definition statement

This place covers:

  • Transition between different power-saving modes
  • Conditions of entry into a sleep mode
  • Wake-on LANs
  • Energy Efficient Ethernet (IEEE 802.3az)

It covers activation or deactivation of terminals or nodes connected to a network. Sometimes, a power on/off is involved, while other documents deal more with logical (de-)activations.

References
Limiting references

This place does not cover:

Power modes management in wireless networks

H04W 52/02

Informative references

Attention is drawn to the following places, which may be of interest for search:

Details regarding the setting of the power status of a node according to activity on a bus

H04L 12/40039

Glossary of terms

In this place, the following terms or expressions are used with the meaning indicated:

WoL

Wake-on-LAN

Charging {, metering or billing} arrangements {for data wireline or wireless communications}
Definition statement

This place covers:

Aspects of billing, charging, accounting, tariffing for the transport of data packets in wireless or wireline data networks, including data sub networks of voice networks.

Relationships with other classification places

G06Q: data processing systems or methods, specially adapted for administrative, commercial, financial, managerial, supervisory or forecasting purposes.

H04M: telephonic communication.

H04W: wireless communications networks.

References
Application-oriented references

Examples of places where the subject matter of this place is covered when specially adapted, used for a particular purpose, or incorporated in a larger system:

Arrangements for maintenance or administration with service quality level based billing

H04L 41/5029

Metering arrangements in telephonic communication, such as billing and charging of telephone calls or the billing architecture of telephonic networks.

H04M 15/00

Prepayment voice telephony systems

H04M 17/00

Accounting or billing for services or facilities specially adapted for wireless communication

H04W 4/24

Informative references

Attention is drawn to the following places, which may be of interest for search:

Payment schemes, architectures or protocols

G06Q 20/00

Billing for commerce in data processing systems or methods specially adapted for administrative, commercial, financial, managerial, supervisory or forecasting purposes; this includes the non-technical aspects that relate to billing and charging in data networks

G06Q 30/00

Special rules of classification

Features for which there is no matching subgroup under H04L 12/14 should be classified under H04M 15/00 or H04M 17/00 if appropriate subgroups are provided there.

{Architecture for metering, charging or billing}
Definition statement

This place covers:

This group is used for features related to the interrelation between network nodes, addition of new network nodes, software downloaded to user, self-billing, sampling, backup of billing data, etc. for charging purposes.

{Policy-and-charging control [PCC] architecture}
Definition statement

This place covers:

Charging aspects of the Policy and Charging Rules Function / Policy Charging Rules Node, or Policy and Charging Control architectures.

Special rules of classification

If flow control or admission control aspects are relevant, this is classified in H04L 47/20 , H04L 47/70 or H04W 28/10.

If network maintenance or administration aspects are relevant, this is classified in H04L 41/0893.

{in real-time}
Definition statement

This place covers:

Advice of charge (AoC) during a communication.

{Advice of charge with threshold, e.g. user indicating maximum cost}
Definition statement

This place covers:

Advice of charge (AoC) with a threshold, e.g. user indicating maximum cost.

{Indication of expected costs}
Definition statement

This place covers:

This includes e.g. providing the user a preview of estimated costs before he/she starts a communication, for example before start of a file transfer.

{involving dedicated fields in the data packet for billing purposes}
Definition statement

This place covers:

Special fields, for example in IP-headers of SIP-headers, used for charging or billing.

{Invoice generation, e.g. customization, lay-out, database processing, algorithms for calculating the bill or formatting invoices as WWW pages (invoicing in general G06Q 30/04)}
References
Limiting references

This place does not cover:

Invoicing in general

G06Q 30/04

{Metric aspects}
Definition statement

This place covers:

This group is used for metric aspects whereby the charging is based neither on volume nor on time, for instance based on distance / number of hops, or the use of more complicated formulas for determining the charging.

{volume-based}
Definition statement

This place covers:

This group is used for exceptional volume based charging, for instance only charging for volume of useful data, not overhead data (overhead data being for example: session set-up / tear down, retransmission of erroneous packets).

{time-based}
Definition statement

This place covers:

This group is used for exceptional time based charging, for example only charging for actual transmission time, or time based charging where this would otherwise be uncommon.

{inter-operator billing}
Definition statement

This place covers:

This includes for example: clearing of revenue, format conversion, meta format for billing.

{trading network capacity or selecting route based on tariff}
Definition statement

This place covers:

This includes for example the exchanges for trading the capacity, or selecting operators / routes based on tariff.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Arrangements for maintenance or administration with service quality level based billing,

H04L 41/5029

{Methods or systems for payment or settlement of the charges for data transmission involving significant interaction with the data transmission network}
Definition statement

This place covers:

Aspects of payment or settlement of charges involving interaction with the data transmission network, see the subgroups below.

{using digital cash}
Definition statement

This place covers:

Payment using e-cash, credit units, tokens, points.

{involving prepayment}
Definition statement

This place covers:

Features related to prepayment accounts are classified here.

Special rules of classification

The on-line / real-time metering / charging aspects are additionally classified under "Architecture" by tagging with the subgroup code H04L 12/1403.

More detailed features are classified under H04M 17/00.

{the splitting involving a third party}
Definition statement

This place covers:

Cost splitting involving a third party, such as an advertiser, a sponsor.

This could include a discount to the user based on the acceptance of an advertisement where e.g. the advertiser pays the remaining amount.

Even when the third party bears the full cost, this is still classified here.

{the splitting involving only the communication parties}
Definition statement

This place covers:

Cost splitting involving only the communication parties, e.g. the "A" party and the "B" party in a standard two-party communication, or additional parties in case of teleconferencing.

{involving use of telephony infrastructure for billing for the transport of data, e.g. call detail record [CDR] or intelligent network infrastructure}
Definition statement

This place covers:

This includes e.g. the use of call detail record CDR, or the Intelligent Network infrastructure.

{Tariff-related aspects}
Definition statement

This place covers:

This includes variable tariff dependent on subscription-contract, time-of day, flow, QoS/diffserv, bandwidth usage.

Aspects related to network maintenance or administration with service quality level based billing are also classified under H04L 41/5029.

{dependent on congestion}
Definition statement

This place covers:

This includes variable tariffs dependent on congestion, i.e. congestion pricing.

{negotiation of tariff}
Definition statement

This place covers:

This includes negotiation of the tariff, between the user and the provider, or between providers. Also automatic negotiation by algorithms, i.e. without user involvement, is classified here.

{involving discounts}
Definition statement

This place covers:

Discounts on the overall charge where only one communication party, typically the "A" party, pays the cost.

Special rules of classification

If another communication party is involved, this is classified under H04L 12/1475 .

for broadcast or conference {, e.g. multicast}
Definition statement

This place covers:

  • Computer conferences, e.g. whiteboard applications or multimedia conferences, which take place (at least partially) over a data switching network.
  • Multicast transmission, since it is considered as a kind of restricted broadcast.

It is a subgroup of H04L 12/00 and hence contains only documents with broadcast, multicast or conference arrangements in data switching networks, and where there is a disclosure of subject-matter relevant for the broadcast, multicast or conference per se.

Further details of subgroups

This subgroup is not active and contains networks adapted for stock quotations. Computer supported buying and selling of stocks without network aspects is classified in G06Q 40/04 .

This subgroup is not active and contains networks specifically adapted for auctions. Computer supported auctioneering such as Internet auctions without network aspects is classified in G06Q 30/08 .

This subgroup includes documents regarding data exchange in real-time between a group of user equipment connected to a data-switching network. The documents provide solutions suitable for groups of more than two pieces of user equipment but do not exclude two users in a degenerate situation.

Instant messaging is classified in H04L 51/04.

This subgroup contains documents related to conference administration arrangements for setting up and starting a conference. It covers aspects related to events before the actual conference takes place.

This subgroup contains documents related to conference administration arrangements during the conference itself.

Examples of documents classified here: US2007274460, US7408890, US7426540.

This subgroup contains documents directed to solving problems such as transmission errors and/or delays, and terminals with limited capabilities.

Examples of documents classified here: EP1876755, WO2004008336

This subgroup contains documents directed to the recording of conference content, participant activities and/or behaviour, etc. for later retrieval.

This subgroup contains documents where not all the receivers of the broadcast or multicast data are connected through the same kind of networks, which influences the broadcast/multicast service.

This subgroup contains documents where not all the receivers have the same capabilities, which influences the broadcast/multicast service.

Layered encoding of data as such is classified in H04N 19/00.

The size of the location is not relevant; the data transmission can take place within a room, a building, a city, or a nation etc. (location of the user terminal in data switching networks H04L 67/52; services specially adapted for wireless communication networks making use of the location of users or terminals H04W 4/02)

This subgroup contains inter alia documents related to the IGMP or MLD protocols for joining and leaving a multicast group.

It also contains documents dealing with changes to the multicast service as the result of a node failure or a member joining or leaving the group.

Routing tree calculation is classified in H04L 45/48 .

This subgroup contains documents dealing with systems where the data forwarding to every receiver is also the responsibility of the receivers themselves, e.g. application layer multicast.

This subgroup covers documents where the multicast or broadcast aspect is relevant for the push service, such as pushing common data to a group of users. Pushed-based network services H04L 67/55.

Push systems in relation to Internet retrieval, see G06F 16/951.

This subgroup contains documents dealing with the problem of how to make sure that each receiver has received the data and what to do when this is not the case.

This subgroup contains documents dealing with any action (e.g. verifications, increased resources, alternative paths, etc.) taken prior to transmission in order to ensure network reliability. Arrangements for detecting or preventing errors in received information in general, see H04L 1/00.

This subgroup contains documents concerning the transmission order of multicast and/or broadcast data packets onto the network, e.g. vis-à-vis unicast data.

The restrictions are for instance applied to avoid flooding of data by dividing the recipients into multicast groups or using subnets or subdomains.

This subgroup only contains documents dealing with multicast or broadcast problems that are a result of (at least some) network links being wireless, e.g. intermittent connectivity or bandwidth constraints.

Documents concerned with the wireless part of the network for broadcast or multicast services such as MBMS are classified in H04W 4/06, e.g. radio channel allocation.

This subgroup contains documents where real-time information is unidirectionally communicated to a group of recipients.

Relationships with other classification places

H04H: Broadcast communication in broadcast networks, e.g. radio or television networks.

H04N: Pictorial communication, e.g. television.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Routing aspects for multicast

H04L 45/16

Flow control for multicast

H04L 47/18

Packet switches for multicast or broadcast

H04L 49/201

Arrangements for multi-party communication, e.g. for conferences

H04L 65/403

Push-to services, e.g. push-to-talk or push-to-video

H04L 65/4061

Network services for supporting one-way streaming services

H04L 65/61

Telephone conferences

H04M 3/56

Video conferences

H04N 7/15

Arrangements for the radio link of a wireless network for broadcast or multicast services such as MBMS, e.g. radio channel allocation

H04W 4/06

Push-to-Talk [PTT] or Push-On-Call services

H04W 4/10

Special rules of classification

The rule for classification in this group is "multiple places, no priority". This means that a document should be classified in all the subgroups that are appropriate for the document.

Glossary of terms

In this place, the following terms or expressions are used with the meaning indicated:

Chat room

A chat room is a special type of computer conference where the users normally are not aware of the (true) identities of other participants' before joining the chat. The chat room application executes mainly on a server which is often accessed through a web browser. No participant has control over the admission of other participants.

Instant messaging, IM

Instant messaging is data exchange in real-time between at least two end users connected to a packet-switching network where the users are aware of the identity and the presence of the other party or parties before starting the data exchange.

{for computer conferences, e.g. chat rooms (instant messaging H04L 51/04; protocols for multimedia communication H04L 65/1101; arrangements for multi-party communication H04L 65/403; telephonic conference arrangements H04M 3/56; television conference systems H04N 7/15)}
References
Limiting references

This place does not cover:

Instant messaging

H04L 51/04

Protocols for multimedia communication

H04L 65/1101

Arrangements for multi-party communication

H04L 65/403

Telephonic conference arrangements

H04M 3/56

Television conference systems

H04N 7/15

{broadcast or multicast in a specific location, e.g. geocast (protocols for adapting network applications to user terminal location H04L 67/52; services specially adapted for wireless communication networks making use of the location of users or terminals H04W 4/02)}
References
Limiting references

This place does not cover:

Protocols for adapting network applications to user terminal location

H04L 67/52

Services specially adapted for wireless communication networks making use of the location of users or terminals

H04W 4/02

Arrangements for preventing the taking of data from a data transmission channel without authorisation (means for verifying the identity or the authority of a user of a secure or secret communication system H04L 9/32)
Relationships with other classification places

This subgroup was initially used to classify network security aspects, which are now classified in:

  • H04L 63/00: Network architectures or network communication protocols for network security and/or
  • H04W 12/00: Network architectures or network communication protocols for wireless network security
References
Limiting references

This place does not cover:

Cryptographic means for verifying the identity or authority of a user of the system

H04L 9/32

characterised by path configuration, e.g. LAN [Local Area Networks] or WAN [Wide Area Networks] (wireless communication networks H04W {; arrangements for dividing the transmission path H04W 40/00})
Definition statement

This place covers:

Header group accommodating those networks whose topology respond to regular LAN topologies (bus, ring or star). His head group contains also WAN and MAN topologies. Documents dealing with very generic network topologies on Layer 2 should be classified here.

References
Limiting references

This place does not cover:

Wireless communication networks

H04W

Arrangements for dividing the transmission path

H04W 40/00

Informative references

Attention is drawn to the following places, which may be of interest for search:

Connectivity information management, e.g. connectivity discovery or connectivity update

H04W 40/24

{Broadband local area networks}
Definition statement

This place covers:

  • DOCSIS-related technologies (cable modems, cable modem termination systems);
  • MoCA networks;
  • HFC networks.

This group concerns mostly cable modems and developments of data services on existing cable infrastructures. One can find in this group variations on the basic IEEE 802.14 standard for accessing an optical cable using mostly TDMA. Some architectures for access to video on demand networks using HFC (Hybrid Fibre Coax) physical media. Of course some LANs using ATM as transport technology are also to be fund in the group.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Cryptographic protocols

H04L 9/00

Point-to-multipoint connection of the data network to end users in an access network

H04L 12/2861

Arrangements for combining access network resources elements, e.g. channel bonding

H04L 12/2863

Network security protocols

H04L 63/00

Real-time communication protocols in data switching networks

H04L 65/00

Network protocols for data switching network services

H04L 67/00

Telephony over cable network

H04M 7/006

Video on demand and video coding

H04N 7/173, H04N 7/24

Glossary of terms

In this place, the following terms or expressions are used with the meaning indicated:

DOCSIS

Data Over Cable Service Interface Specification

CMTS

Cable Modem Termination System

CM

Cable Modem

MoCA

Multimedia over COAX Alliance

{Home automation networks}
Definition statement

This place covers:

Network of appliances in a same home exchanging within said network messages which are generic with regard to the type of appliance.

This group covers all network aspects of domotics.

It covers:

  • Transmission media such as power transmission lines or dedicated wiring for controlling home appliances;
  • Using the home telephone wiring for building a LAN. HomePNA(Phone-line Networking Alliance).
  • Addressing issues concerning the identification of devices in different
  • areas of a dwelling
  • Network control. Using e.g. a regular TV receiver or dedicated terminal Tapping devices used to connect appliances to the selected wiring (Echelon's LON network).
  • Some standard architectures for home control use: CEBUS or FieldBus, PNA.
References
Limiting references

This place does not cover:

Factory automation

G05B 19/418

Transmission of data over power lines

H04B 3/54

Remote control of lights using a control bus

H05B 47/18

Informative references

Attention is drawn to the following places, which may be of interest for search:

Access arrangements

H04L 12/2856

High-speed IEEE 1394 serial bus

H04L 12/40052

Single bridge functionality

H04L 12/4625

Network monitoring

H04L 43/00

Device-related reporting

H04L 43/065

Monitoring functionality

H04L 43/0817

Arrangements for network security

H04L 63/00

Web-based protocols

H04L 67/02

Remote control or remote monitoring of applications in data packet switching networks

H04L 67/025

Discovery or management thereof, e.g. service location protocol [SLP] or web services

H04L 67/51

Protocol conversion

H04L 69/08

Retrieval from the Internet

G06F 16/95

Arrangements for transmitting signals characterised by the use of a wireless electrical link

G08C 17/00

Telephonic communication systems adapted for combination with telemetering systems

H04M 11/002

Telephonic communication systems adapted for combination with remote control systems

H04M 11/007

Adaptations of television systems for transmission by electric cable for domestic distribution

H04N 7/106

Receiver circuitry for displaying additional information being controlled by a remote control apparatus

H04N 21/42204

Arrangements in telecontrol or telemetry systems for selectively calling a substation from a main station, in which substation desired apparatus is selected for applying a control signal thereto or for obtaining measured values therefrom

H04Q 9/00

Special rules of classification

This group covers all network aspects of domotics.

The following topics are well represented in the group:

Use of networks (involving wireless links, power transmission lines, home telephone wiring) for controlling or monitoring home appliances or for exchanging control messages between audio video appliances.

In the definition above, the following criteria are emphasized:

  • There should be at least one network of appliances; this condition is not fulfilled for a simple application of remote control of a heating system by telephone or Internet;
  • The devices connected to the network are appliances, i.e. devices having a sensor or actor role in the home automation; a network involving printers and computers (these computers having no appliance function) only does not fulfill this condition;
  • There should be general aspects of the network, i.e. aspects which are not specific to a single type of application; this is the case for instance when the invention relates to a message data field used for controlling appliances, but not if the invention concerns specifically the use of a few commands to accomplish a certain operation; this difference can be understood as a difference of layer;

The subgroup relates to control or monitoring with several appliances in a same home; this condition is not fulfilled when the appliances are communicating only via the Internet or the mobile cellular network; this condition is also not fulfilled by the interconnection of audio-video devices with their broadcast network; hotels can be considered as home if the privacy concept coincides with the hotel; building automation of purely mechanical and lighting devices can be considered as a home if it is separate from the city infrastructure.

{Home Audio Video Interoperability [HAVI] networks}
Definition statement

This place covers:

HAVi networks encompasses connections to control Audio and Video hardware using FireWire.

Glossary of terms

In this place, the following terms or expressions are used with the meaning indicated:

HAVi

Home Audio Video Interoperability

{Exchanging configuration information on appliance services in a home automation network (arrangements for maintenance or administration involving network analysis for automatically determining the actual topology of a network H04L 41/12; hardware or software tools for network management using graphical user interfaces H04L 41/22; address allocation H04L 61/50)}
Definition statement

This place covers:

Exchange and retrieval of information regarding which element having which attributes are present in the network.

References
Limiting references

This place does not cover:

for automatically determining the actual topology of a network

H04L 41/12

using GUI (Graphical User Interface)

H04L 41/22

Address allocation

H04L 61/50

{indicating that an appliance service is present in a home automation network (monitoring functionality H04L 43/0817; discovery or management thereof, e.g. service location protocol [SLP] or web services, H04L 67/51)}
Definition statement

This place covers:

Exchange of information indicating which services or operations are available on the home network appliances.

References
Limiting references

This place does not cover:

based on functioning

H04L 43/0817

Arrangements for service discovery, e.g. Service Location Protocol

H04L 67/51

Informative references

Attention is drawn to the following places, which may be of interest for search:

Discovering of devices as part of configuration

H04L 41/08

Address allocation to terminals or nodes connected to a network

H04L 61/50

{indicating a format for calling an appliance service function in a home automation network (for remote control or remote monitoring of applications H04L 67/025)}
Definition statement

This place covers:

Description of capabilities of devices and services in a home network.

Exchange of information describing access methods and parameters of devices or services available on the home network appliances.

Emphasis is on "description", i.e. the data structure indicating the commands and parameters with which control of the operation of a device's appliance can be triggered.

References
Limiting references

This place does not cover:

Network monitoring

H04L 43/00

Remote control or remote monitoring of applications in data packet switching networks

H04L 67/025

{describing content present in a home automation network, e.g. audio video content (retrieval from the Internet G06F 16/95)}
Definition statement

This place covers:

Description of contents available in a home network. Exchange of information describing contents available on the home network appliances. Emphasis is on "contents".

References
Limiting references

This place does not cover:

Web-based protocols

H04L 67/02

Information retrieval from the Internet

G06F 16/95 - G06F 16/9577

{Exchanging control software or macros for controlling appliance services in a home automation network (arrangements for maintenance or administration involving configuration of the network and network elements H04L 41/08)}
Definition statement

This place covers:

Self explanatory, pieces of software, firmware used to control home appliances.

References
Limiting references

This place does not cover:

Configuration management of network or network elements

H04L 41/08

Informative references

Attention is drawn to the following places, which may be of interest for search:

Network arrangements or protocols for supporting network services or applications in data packet networks

H04L 67/00

Program loading or initiating

G06F 9/445 - G06F 9/44594

{Controlling appliance services of a home automation network by calling their functionalities (arrangements in telecontrol or telemetry systems for selectively calling a substation from a main station; in which substation desired apparatus is selected for applying a control signal thereto or for obtaining measured values therefrom H04Q 9/00)}
Definition statement

This place covers:

Exchange of information that triggers action of at least one device.

References
Limiting references

This place does not cover:

Arrangements in telecontrol or telemetry systems for selectively calling a substation from a main station, in which substation desired apparatus is selected for applying a control signal thereto or for obtaining measured values therefrom

H04Q 9/00

{from a device located outside both the home and the home network (access arrangements H04L 12/2856; for remote control or remote monitoring of applications H04L 67/025; arrangements for transmitting signals characterised by the use of a wireless eletrical link G08C 17/00; telephonic communication systems adapted for combination with remote control systems H04M 11/007)}
Definition statement

This place covers:

Complex home network provisions for being remotely accessed. Access to a home network (with at least two appliances) from a device outside the home network.

media5.png

In that example, a device control processor which communicates with a remote access service unit and operating a home network device using universal plug and play (UPnP) message, stores list of controlled devices, each device state, event list and service request list.

The processor converts request/message received from service unit/UPnP device into message/request for transmission to respective units.

References
Limiting references

This place does not cover:

Access arrangements, e.g. Internet access

H04L 12/2856

Remote control or remote monitoring of applications in data packet switching networks

H04L 67/025

Arrangements for transmitting signals characterised by the use of a wireless electrical link

G08C 17/00

Remote control via a telephone connection

H04M 11/007

{based on user interaction within the home (receiver circuitry for displaying additional information being controlled by a remote control apparatus H04N 21/42204)}
Definition statement

This place covers:

User interaction from within network for the control of appliances, e.g. through remote controller, PDA, cell phone, RF ID etc.

References
Limiting references

This place does not cover:

User interface for managing and configuring a home network

H04L 41/00

Receiver circuitry for displaying additional information being controlled by a remote control apparatus

H04N 21/42204

{Avoiding conflicts related to the use of home appliances (cryptographic protocols H04L 9/00; protocols for network security H04L 63/00)}
Definition statement

This place covers:

The home appliance or another device prevents the home appliance from having to execute commands which disturb ongoing operations.

References
Limiting references

This place does not cover:

Cryptographic protocols

H04L 9/00

Network security protocols

H04L 63/00

Informative references

Attention is drawn to the following places, which may be of interest for search:

Network access security

H04L 63/10

{Reporting information sensed by appliance or service execution status of appliance services in a home automation network (device-related reporting H04L 43/065; arrangements in telecontrol or telemetry systems for selectively calling a substation from a main station, in which substation desired apparatus is selected for applying a control signal thereto or for obtaining measured values therefrom H04Q 9/00)}
Definition statement

This place covers:

Exchange of information for reporting or monitoring the operation of home appliances so as to trigger operation of other home appliance functions. The status of a service or the sensed situation of an appliance is advertised on a home network for reaction by other home devices to create an environment conforming to specific rules or profiles.

media6.png

media7.png

In that document, the rules of device interaction may include instructions that are to be transmitted from the aggregator in response to the aggregator receiving change of state messages from devices of the environment.

References
Limiting references

This place does not cover:

Advertising the status of network devices

H04L 41/00

Alarm systems in general

G08B 25/00

Arrangements in telecontrol or telemetry systems for selectively calling a substation from a main station, in which substation desired apparatus is selected for applying a control signal thereto or for obtaining measured values therefrom

H04Q 9/00

{Reporting to a device located outside the home and the home network (access arrangements H04L 12/2856; for remote control or remote monitoring of applications H04L 67/025; telephonic communication systems adapted for combination with telemetering systems H04M 11/002)}
Definition statement

This place covers:

Self-explanatory : reporting the operation of home appliances or a particular network event affecting a home appliance to one or more external devices, i.e. to devices outside the home network.

References
Limiting references

This place does not cover:

Access arrangements

H04L 12/2856

For remote control or remote monitoring of applications

H04L 67/025

Telephonic communication systems adapted for combination with telemetering systems

H04M 11/002

Informative references

Attention is drawn to the following places, which may be of interest for search:

Network monitoring in data packet switching networks

H04L 43/10

{Reporting to a device within the home network; wherein the reception of the information reported automatically triggers the execution of a home appliance functionality}
Definition statement

This place covers:

Self explanatory: in contrast to the preceding class, the exchange of messages only occurs among home appliances within the same home automation network.

{involving user profiles according to which the execution of a home appliance functionality is automatically triggered}
Definition statement

This place covers:

Self explanatory: a user profile defines rules or a policy for triggering specific actions or the emission of a command to a device in response to the occurrence of an event at a given home appliance.

{Processing of data at an internetworking point of a home automation network}
Definition statement

This place covers:

Device adapted to communicate with different types of networks.

{Interconnection of the control functionalities between home networks (single bridge functionality H04L 12/4625)}
Definition statement

This place covers:

Bridges between home networks (e.g. HAVi/UPNP).

Home gateway performing interface adaptation (also lower layer adaptation, kind of bridge).

media8.png

References
Limiting references

This place does not cover:

Single bridge functionality

H04L 12/4625

Informative references

Attention is drawn to the following places, which may be of interest for search:

Bridging devices

H04L 12/462

Protocols for interworking; Protocol conversion

H04L 69/08

Multiprotocol handlers, e.g. single devices capable of handling multiple protocols

H04L 69/18

{Switching of information between an external network and a home network (access arrangements H04L 12/2856)}
Definition statement

This place covers:

Switching (or forwarding, routing) at a gateway between external network(s) and home network(s). Contains operational details on residential/home gateways.

References
Limiting references

This place does not cover:

Multiplexing of signals from an external network for distribution to the home network

H04L 12/2838

Access arrangements

H04L 12/2856

Bridging devices

H04L 12/462, H04L 12/4625

{Protocol conversion between an external network and a home network (controlling appliance services of a home automation network from a device located outside the home and the home network H04L 12/2818; protocol conversion H04L 69/08; adaptation of digital video signals for transport over a specific home network H04N 7/24)}
Definition statement

This place covers:

Protocol conversion between home network(s) and external network(s). If the conversion is only from one controlling protocol to another, the corresponding Indexing Code entry should be used.

References
Limiting references

This place does not cover:

from a device located outside both the home and the home network

H04L 12/2818

Protocol conversion

H04L 69/08

Informative references

Attention is drawn to the following places, which may be of interest for search:

Multiprotocol handlers, e.g. single devices capable of handling multiple protocols

H04L 69/18

{Distribution of signals within a home automation network, e.g. involving splitting/multiplexing signals to/from different paths (adaptations of television systems for transmission by electric cable for domestic distribution H04N 7/106; hybrid transport H04L 12/6418; home network arrangements specially adapted for distribution of digital video signals H04N 7/24)}
Definition statement

This place covers:

Distribution of signals within a home network. Data signal distribution from/to appliances within the home network. The mere transmission of signals in a home network without a particular way to convey said signal in the home network should not be classified here.

Example: WO2006100515.

media9.png

The main aspect of the document is that the signals are all distributed in the home through one Ethernet cable on which all packets are transmitted according to TCP/IP. There are no improvements to the TCP/IP no details on the head end and the switching within the head end. No details about control of devices, that's why signal distribution appears to be the only main aspect within home network.

Second example: US6751441

media10.png

Signals from cable network are split into TV and data signals; the data signals are modulated at the WLAN frequency but distributed to the rooms along the cables. Within the rooms the signals are radiated through an antenna.

References
Limiting references

This place does not cover:

Hybrid transport

H04L 12/6418

Domestic distribution of TV signals

H04N 7/106

{Metropolitan area networks}
Definition statement

This place covers:

A MAN, Metropolitan Area Network, refers to the access technology as well as to the size. The reference book "Computer Networks" written by Tanenbaum gives a definition of it: "A MAN is a network that covers an entire city, but uses LAN technology".

{Wide area networks, e.g. public data networks}
Definition statement

This place covers:

This group is very general about WANs. It contains public data networks such as Frame Relay and X.25 packet networks.

{Access arrangements, e.g. Internet access (asynchronous transfer mode networks H04L 12/5601; broadband local area networks H04L 12/2801; optical access or distribution networks H04Q 11/0067; access to open networks H04L 12/5691; digital subscriber line end-user equipment and bit-level processing of data on a PSTN-based network H04M 11/00; home network gateways H04L 12/2834; wireless access networks H04W)}
Definition statement

This place covers:

An access network is a part of a global wired communication network that connects subscribers to their service providers in the public data network.

It consists generally of end-user equipments connected to an access multiplexer. The access multiplexer is connected to an access server through an aggregation network, wherein the access server is the interface between the access network and the public data network.

media11.png

References
Limiting references

This place does not cover:

Switching of information between an external network and a home network

H04L 12/2834

Management of WDM parameters in optical multiplex systems

H04J 14/02

Access arrangements for providing telephone service in networks other than PSTN/ISDN

H04M 7/0066

Circuit-switched access networks

H04M 7/1205

Telephonic communication systems adapted for combination with other electrical systems

H04M 11/00

Transfer of video data (multimedia streaming) from a video content server to a subscriber

H04N 7/173

Wireless communications networks

H04W

Informative references

Attention is drawn to the following places, which may be of interest for search:

Access to a packet-switched data network over a hybrid coaxial infrastructure

H04L 12/2801

Asynchronous Transfer Mode (ATM) networks

H04L 12/5601

Access to open networks

H04L 12/5691

Admission & flow control, QoS management

H04L 47/10

Addressing and naming aspects

H04L 61/00

Establishment of secure connections and subscriber authentication

H04L 63/00

Digital subscriber line end-user equipment, DSL modems, xDSL splitters, and bit-level processing of data on PSTN-based network

H04M 11/062

Provision of optical access or distribution networks

H04Q 11/0067

Wireless access networks

H04W

{Access network architectures}
Definition statement

This place covers:

There are various ways to deploy an access network, but most of them rely on an existing wired infrastructure. Originally, access to the Internet was mostly provided by DSL access technologies, where a point-to point connection between a subscriber and a service provider is provisioned via a PPP over ATM connection, thereby re-using the existing wired network and their functionalities (ATM PVCs). Nowadays, the trend is clearly to integrate Ethernet as carrier technology for access network segments while remaining the main carrier for the backbone networks, thereby coping with the increasing demand for value-added services such as VoIP, HDTV, IPTV and Triple-Play. In parallel to the development of DSL access technologies, broadcast networks such as cable and optical networks are more and more employed to convey data packets in addition to other signal types, such as video or audio streaming.

References
Limiting references

This place does not cover:

Access to open networks, incl. selection between different service providers

H04L 12/5691

{Point-to-point connection between the data network and the subscribers (encapsulation H04L 12/4633; virtual LANs H04L 12/4641; routing of packets H04L 45/00)}
Definition statement

This place covers:

This group covers essentially the original access technologies wherein a connection between an end-user and the service provider is established by means of a point-to-point protocol, over various types of aggregation networks, such as ATM or Ethernet (PPPoX sessions). This group also includes pseudo-wire techniques, i.e. encapsulation over an IP-based access network.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Packet Encapsulation

H04L 12/4633

Virtual Local Area Networks

H04L 12/4641

ATM networks

H04L 12/5601

Routing of packets

H04L 45/00

Special rules of classification

This group has a quite broad definition and ideally should not be the only symbol allocated to a document dealing with access networks. Only documents focusing on the access network infrastructure taken as a whole, i.e. from the public data network to the end-user device, implementing a form of point-to-point technology shall be allocated this subclass as unique symbol.

{Point-to-multipoint connection from the data network to the subscribers}
Definition statement

This place covers:

In this entry, new access technologies relying on the existing cable infrastructure (e.g. DOCSIS, MoCA) or optical networks (PONs) are addressed. Data is transmitted over a shared communication medium on the downlink and the uplink. On the downlink, data is broadcast by the service provider to all subscribers, and each subscriber extracts the data which is aimed to him, out of the stream of multiplexed data.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Broadband Local Area Networks

H04L 12/2801

Provision for optical access or packet networks

H04Q 11/0067

Special rules of classification

See the reasoning for the symbol H04L 12/2859.

{Arrangements for combining access network resources elements, e.g. channel bonding (modem pooling H04L 25/14; routing of packets H04L 45/00; multichannel or multilink protocols H04L 69/14)}
Definition statement

This place covers:

Aspects related to an optimized usage of the available access network resources in order to enable provision of greedy multimedia services over bandwidth-limited access networks. This could consist of bundling subscriber lines, arranging a logical combination of network resources, such as frequency bands on a HFC network or the simultaneous usage of multiple PPPoX connections for transporting the same data service.

References
Limiting references

This place does not cover:

Multichannel or multilink protocols

H04L 69/14

Informative references

Attention is drawn to the following places, which may be of interest for search:

Modem pooling

H04L 25/14

Routing of packets

H04L 45/00

Virtual concatenation in SDH/OTN networks

H04J 2203/0094

{Logical combinations}
Definition statement

This place covers:

Essentially, comprises arrangements for multiplexing individual subscriber connections or grouping of frequency slots on a cable network. The emphasis is on the combination of logical or abstract entities, i.e. frequency or bandwidth resources combinations, not physical entities such as cables or hardware elements.

{Physical combinations}
Definition statement

This place covers:

Refers to the concept of grouping or combining physical access network resources such as devices, interfaces, wires, cables, in order to enhance the total throughput provided to a given subscriber.

{Operational details of access network equipments (admission control or resource allocation in access networks H04L 12/5692)}
Definition statement

This place covers:

Functional characteristics of various devices commonly present in an access network.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Admission control & resource allocation in access networks

H04L 12/5692

{Remote access server, e.g. BRAS}
Definition statement

This place covers:

A remote access server is a device that routes traffic to and from an access multiplexer (e.g. DSLAM) on a public data network.

Glossary of terms

In this place, the following terms or expressions are used with the meaning indicated:

BRAS

Broadband Remote Access Server

BAS

Broadband access server

{Termination of subscriber connections}
Definition statement

This place covers:

Covers essentially the handling of PPPoX sessions : how the Point-to-Point sessions are initiated, maintained, or terminated. Only PPPoX-related operations at the remote access server are covered by this subclass.

{Processing of data for distribution to the subscribers}
Definition statement

This place covers:

Details about specific data processing operations for distributing various multimedia flows, originally formatted to optimize their transport through an IP network, over the access network to the subscribers.

The emphasis is on a particular way to re-arrange or adapt a flow received at a remote access server from the public data network before distributing the flow to subscriber(s) over the access network, wherein this particular way reflects the characteristics of the access networks.

Example: a remote access server adds MAC address tag information to a packet received from an ISP.

{Handling of subscriber policies (group policies management H04L 41/0893)}
Definition statement

This place covers:

Differentiated policies for distributing data to subscribers, based for instance on user profiles, time of the day, traffic volume etc.

media12.jpg

References
Limiting references

This place does not cover:

Group management policies

H04L 41/0893

{Access multiplexer, e.g. DSLAM (generic distributed time multiplexers, e.g. TDM/TDMA H04J 3/1694)}
Definition statement

This place covers:

Operational details of an access multiplexer is a device, located normally in a telephone exchange or in multi-dwelling units of a service provider, that connects multiple end-user terminals to a public data network access node (e.g. a BRAS) through an aggregation network. Examples : DSLAM, fiber distribution hubs or active splitters, etc.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Generic distributed time multiplexers, e.g. TDM/TDMA

H04J 3/1694

DSL modem with DSLAM functionalities

H04M 11/062

{characterised by the network type on the uplink side, i.e. towards the service provider network}
Definition statement

This place covers:

Self-explanatory : this group characterizes the access multiplexer by the type of aggregation network used on the uplink (not to the end-user equipment).

{Arrangements interfacing with optical systems (optical network equipment H04B 10/00; optical multiplexers H04J 14/00)}
Definition statement

This place covers:

  • Optical Line Terminals
  • Cable modem Termination System.
References
Limiting references

This place does not cover:

Determination of optical signal parameters (e.g. wavelength) as a function of data characteristics from Layer-2 or above, like VLAN number, IP address, subscriber profile

H04B 10/00

Optical multiplexers

H04J 14/00

Glossary of terms

In this place, the following terms or expressions are used with the meaning indicated:

OLT

Optical Line Terminals

CMTS

Cable Modem Termination System

{characterised by the offered subscriber services}
Definition statement

This place covers:

Self-explanatory: in contrast to the group H04L 12/2879, this group covers the type of connection linking the access multiplexer to subscriber devices.

Special rules of classification

Normally, a document shall be allocated one of the symbols from this group only when the document focuses on the communication services offered between the access multiplexer and the subscriber devices.

{Multiservice, e.g. MSAN}
Definition statement

This place covers:

A Multi-service access Node, also known as a Multi-service access gateway is a device typically installed in a telephone exchange (although sometimes in a roadside serving area interface cabinet) which connects customers' telephone lines to the core network, to provide telephone, ISDN, and broadband such as DSL all from a single platform.

Glossary of terms

In this place, the following terms or expressions are used with the meaning indicated:

MSAN

Multi-service Access Node

MSAG

Multi-service Access Gateway

{Single service}
Definition statement

This place covers:

Self-explanatory. Essentially one DSL type is supported by the access multiplexer.

{characterised by the access multiplexer architecture}
Definition statement

This place covers:

This group covers specific implementation designs of an access multiplexer, e.g. specific hardware resources or line cards arrangements.

media13.jpg

References
Limiting references

This place does not cover:

DSLAM modems

H04M 11/00

{Centralized processing}
Definition statement

This place covers:

All complex traffic processing (e.g. classification, filtering, QoS, etc.) is performed on a single central chip, e.g. on the uplink card.

{Distributed processing, e.g. on line cards}
Definition statement

This place covers:

Some or all complex traffic processing is off-loaded to the line cards, which may include dedicated processors.

Examples : US6587476, US2002159462, US2008101401.

media14.jpg

{Subscriber equipments (DSL modems H04M 11/062; cable modems H04L 12/2801)}
Definition statement

This place covers:

  • Optical Network Units, Optical Line Terminals
  • Set-top boxes
  • Home network access point
  • Cable modems in cable networks, e.g. DOCSIS

Entry concerning the design of devices carrying out generic L2 or L3 data processing operations, located at the interface between a private or home environment and the access network.

References
Limiting references

This place does not cover:

Broadband local area networks

H04L 12/2801

Home network gateways, residential gateways

H04L 12/2834

DSL modems and xDSL splitters

H04M 11/062

Special rules of classification

This subclass shall only be allocated to documents giving operational details of subscriber equipments which interact with other access network devices, e.g. via the exchange of messages. The sole description of a stand-alone end-user device without any active connection to an access network shall not be classified in H04L 12/2898.

Bus networks
Definition statement

This place covers:

A bus network includes one or a plurality of shared communication lines interconnecting at least 3 distant stations, wherein data is transferred serially in the form of frames or bitstrings along the bus.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Transmission of data and power over a link, and not over a bus network as defined above

H04L 12/10

Serial data transmission over a shared medium having a ring or star topology

H04L 12/42, H04L 12/44

Fibre-channel aspects related to topology, i.e. ring, or switch architecture

H04L 12/42, H04L 49/00

Bus networks including at least one bridging device

H04L 12/4625

Bus networks employed restrictively for a specific automotive application (e.g. power steering, brake-by-wire)

B60R, B62D

Bus systems being deployed on an airplane specifically for controlling parts of an aircraft

B64C 13/503

Bus to control actuators/sensors or any other industrial appliance in an automation system

G05B 19/00

Parallel bus systems

G06F 13/00

Daisy chain buses using an embedded synchronisation

G06F 13/426

Point-to-point communication between 2 stations over a bus

G06F 13/4265

Wireless networks comprising several communication nodes using contention resolution mechanisms

H04W 74/08

{Architecture of a communication node (current supply arrangements H04L 12/10; intermediate storage or scheduling H04L 49/90)}
Definition statement

This place covers:

Details on the hardware elements comprised in a bus communication node. In particular, this class covers the inter-working of the various hardware components and implementation details of specific hardware components. A document shall get an EC code from this group only if the document deals with a particular inventive hardware or software realization. If the document includes the mere illustration of a hardware or software design for implementing a protocol, this document shall only get an Indexing Code in this group.

Example : A FlexRay communication node:

media15.jpg

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Current supply arrangements for the communication nodes

H04L 12/10

Intermediate storage or scheduling

H04L 49/90

Hardware architecture of a processing unit in general

G06F

{Details regarding a bus controller}
Definition statement

This place covers:

A bus controller refers to a microprocessor that is dedicated to input and output of data by a node on a bus. Structure of a carrier sense functionality is also classified here.

{Details regarding a bus master}
Definition statement

This place covers:

A bus master is a device controlling which node accesses the bus at particular time. See also H04L 12/403 for access control aspects

{Details regarding a bus guardian}
Definition statement

This place covers:

A bus guardian is a device monitoring the timing of node accesses on the bus, used for instance in FlexRay systems to avoid babbling idiots (faulty, continuously sending nodes).

References
Limiting references

This place does not cover:

Passive fault-masking in a computer environment

G06F 11/18

{Details regarding a bus interface enhancer}
Definition statement

This place covers:

Interface between the communication line and the other elements of the communication node, having some autonomous functionalities such as message pre-filtering, bus monitoring...

{Details regarding the setting of the power status of a node according to activity on the bus}
Definition statement

This place covers:

Power management aspects, such as management of the transition between various power states (sleep, active or stand-by). These documents shall also be classified in H04L 12/12

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Arrangements for remote connection or disconnection of substations or of equipment thereof

H04L 12/12

{Details regarding the feeding of energy to the node from the bus}
Definition statement

This place covers:

Refers to field devices for instance, which use the voltage and/or current level present on the bus to draw energy from the bus. Note that H04L 12/10 contains documents classified before 2008 having this functionality.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Current supply arrangements

H04L 12/10

{High-speed IEEE 1394 serial bus (bus transfer protocol on a daisy chain bus using an embedded synchronisation G06F 13/426)}
Definition statement

This place covers:

All documents dealing primarily with transmission on a Firewire bus.

References
Limiting references

This place does not cover:

Bus transfer protocol on a daisy chain bus using an embedded synchronization

G06F 13/426

Informative references

Attention is drawn to the following places, which may be of interest for search:

Synchronisation, e.g. post-wait, barriers, locks

G06F 8/458

{Isochronous transmission}
Definition statement

This place covers:

Documents referring generally to synchronization aspects of Firewire communication, incl. jitter compensation and clock synchronizations.

{Bandwidth and channel allocation (home automation networks H04L 12/2803; flow control H04L 47/10)}
Definition statement

This place covers:

Aspects of resource allocation for Firewire networks.

References
Limiting references

This place does not cover:

Home automation networks

H04L 12/2803

Informative references

Attention is drawn to the following places, which may be of interest for search:

Flow control aspects

H04L 47/10

{Packet processing; Packet format (adaptation of digital video signals for transport over a specific network H04N 21/2381, H04N 21/4363, H04N 21/4381; packet switches H04L 49/00; intermediate storage or scheduling H04L 49/90)}
Definition statement

This place covers:

Self-explanatory, deals with operations on packets in a Firewire bus system.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Packet switches

H04L 49/00

Intermediate storage or scheduling

H04L 49/90

{Bus configuration (home automation networks H04L 12/2803; arrangements for maintenance or administration H04L 41/00)}
Definition statement

This place covers:

Typically bus reset operations on Firewire.

References
Limiting references

This place does not cover:

Home automation networks

H04L 12/2803

Informative references

Attention is drawn to the following places, which may be of interest for search:

Arrangements for maintenance or administration

H04L 41/00

{Bus arbitration}
Definition statement

This place covers:

Control to the access to the communication medium on Firewire.

{Bus bridging (LAN interconnection over a bridge based backbone H04L 12/462; single bridge functionality H04L 12/462)}
Definition statement

This place covers:

Interconnection aspects in Firewire bus systems.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

LAN interconnection over a bridge based backbone

H04L 12/462

Single bridge functionality

H04L 12/4625

{Interconnection with other networks (LAN interconnection over a bridge based backbone H04L 12/462; single bridge functionality H04L 12/462)}
Definition statement

This place covers:

Gateway to other network sections, to other Firewire networks.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Bridging devices in local area networks

H04L 12/462

{Security; Encryption; Content protection (cryptographic protocols H04L 9/00; protocols for network security H04L 63/00)}
Definition statement

This place covers:

Security aspects in Firewire networks.

References
Limiting references

This place does not cover:

Cryptographic protocols

H04L 9/00

Network security protocols

H04L 63/00

{Interconnection of audio or video/imaging devices (home automation networks H04L 12/2803; bitstream network arrangements specially adapted for distribution of digital video signals H04N 7/24)}
Definition statement

This place covers:

Interconnection with multimedia devices over a FireWire bus.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Home automation networks

H04L 12/2803 - H04L 12/2838

{Interconnection of computers and peripherals (printer information exchange with computer G06F 3/1293)}
Definition statement

This place covers:

Interconnection of computers with specific extension elements such as peripherals over a Firewire bus.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Printer information exchange with computer

G06F 3/1293

{Management of data rate on the bus (systems modifying transmission characteristics according to link quality H04L 1/0001)}
Definition statement

This place covers:

Documents referring generally to the selection of a particular data rate on a bus network, based on different factors, i.e. instantaneous network load. Rate adaptation on a bus maybe be necessary for achieving optimal transmission performance, by finding a good trade-off between packet loss and transmission speed. A LIN bus supports for instance various bitrates.

References
Limiting references

This place does not cover:

Systems modifying transmission characteristics according to link quality

H04L 1/0001

Informative references

Attention is drawn to the following places, which may be of interest for search:

Allocation of payload

H04L 5/0044

Negotiation of transmission parameters of transmission speed prior to communication

H04L 5/1446

{Nodes adapting their rate to the physical link properties (LAN switches H04L 49/351)}
Definition statement

This place covers:

Physical link properties include bus capacity such as 10Mbit/s or 100Mbit/s Ethernet network.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Rate adaptation according to physical link properties such as the detection of the bus capacity being 10Mbit/s or 100Mbit/s Ethernet network at a LAN switch

H01L 29/66469

{involving priority mechanisms (hybrid switching fabrics H04L 12/6402; intermediate storage or scheduling H04L 49/90; time-division multiplex systems H04J 3/00)}
Definition statement

This place covers:

Documents related to the introduction of certain criteria to prioritize the transmission of data on the bus. On a vehicle bus for instance, information about car safety shall have priority over messages carrying monitoring data.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Hybrid switching fabrics

H04L 12/6402

Intermediate storage or scheduling

H04L 49/90

Time-division multiplexing

H04J 3/00

{by scheduling the transmission of messages at the communication node}
Definition statement

This place covers:

Queue management at the transmitting node.

{by using dedicated slots associated with a priority level}
Definition statement

This place covers:

In a TDMA bus communication system, certain time slots might be reserved for transmission of data having a high level of priority.

{by assigning priority to messages according to a message field}
Definition statement

This place covers:

Typically a message field or tag indicates a priority level, which can be read by any node connected to the bus.

{Flexible bus arrangements (arrangements for maintenance or administration involving management of faults; events, alarms H04L 41/06; automatic restoration of network faults H04L 41/0654)}
Definition statement

This place covers:

Documents covering various flexibility aspects, such as fast network re-configuration, flexible topology change, seamless connection or disconnection of a new node to/from the bus. In general, this class covers scalability of bus networks and reconfiguration aspect.

References
Limiting references

This place does not cover:

Arrangements for maintenance or administration involving management of faults; events, alarms

H04L 41/06

Automatic restoration of network faults

H04L 41/0654

{involving redundancy (error detection or correction of the data by redundancy in hardware using active fault-masking in interconnections G06F 11/2002; error detection or correction of the data by redundancy in hardware using active fault-masking in storage systems using spares or by reconfiguring G06F 11/2053)}
Definition statement

This place covers:

Different forms of redundancy which do not correspond to the following related fields.

References
Limiting references

This place does not cover:

Error detection or correction of the data by redundancy in hardware using active fault

G06F 11/2017

where persistent mass storage functionality or persistent mass storage control functionality is redundant

G06F 11/2053

{by using a plurality of communication lines}
Definition statement

This place covers:

A single bus system may comprise at least one back-up communication line, in case of failure of the main communication line. Each station has then typically two or more bus drivers, one for each communication line.

{by using a plurality of bus systems}
Definition statement

This place covers:

Two bus systems running independently of each other may provide protection against problems affecting the whole active bus system.

{by using a plurality of nodes}
Definition statement

This place covers:

Duplication of a part or of an entire communication node in order to ensure fast recovery from a node defect without affecting the bus operations.

{by using a plurality of master stations}
Definition statement

This place covers:

Switching from an active master station to a back-up master station is needed for safety-critical bus systems with centralized access control. See also H04L 12/403.

with centralised control, e.g. polling
Definition statement

This place covers:

Contains documents with a central control node controlling the transmissions on the bus. Polling is known for a long time so a "new" polling scheme could be found in rather old documents (<1970).

{in which slots of a TDMA packet structure are assigned based on a contention resolution carried out at a master unit (TDM/TDMA multiplex systems per se H04J 3/1694; hybrid switching systems H04L 12/64)}
Definition statement

This place covers:

Self-explanatory. Shall not be used for documents dealing with FlexRay in general.

References
Limiting references

This place does not cover:

Hybrid switching systems

H04L 12/64

Allocation of channels in TDM/TDMA networks

H04J 3/1694

with decentralised control
Definition statement

This place covers:

This is a subgroup with general aspects of decentralized control. It contains documents about implicit token passing and some slotted buses.

with random access, e.g. carrier-sense multiple-access with collision detection (CSMA-CD)
Definition statement

This place covers:

Deals with access schemes in which access to the medium is granted at random after an arbitration process in case several nodes send requests simultaneously (collision). CSMA/CD (carrier sense multiple access with collision detection) also called Ethernet (basic document by Xerox US4063220) is one of these schemes. Ethernet aspects not linked with CSMA/CD shall not be classified in this class, but documents concerning some specific Ethernet functionalities such as contention resolution, back-off or interframe gap shall be classified in this group.

{using bit-wise arbitration}
Definition statement

This place covers:

This is a special case for relatively low transmission speeds and/or short buses. Nodes competing for bus access read the superposed signals back from the bus and stop transmission when the bus signal is not identical with the transmitted signal. Many bus systems used e.g. in vehicles can be found in this subgroup.

References
Limiting references

This place does not cover:

Computer buses with bit-wise arbitration

G06F 13/374

Special rules of classification

CAN bus aspects not linked with bit-wise arbitration shall not be classified in this class.

with deterministic access, e.g. token passing
Definition statement

This place covers:

Contains documents with access schemes granting access to requests within a predetermined time limit. On token buses nodes are arranged in a logical ring passing the access right (token) from node to node. Bus networks having a master are not classified here. Aspects of FlexRay related to the deterministic access to static time slots are also classified here.

Loop networks
Definition statement

This place covers:

Deals with networks in which nodes are connected in a physical ring.

{Synchronisation for ring networks (Time Division Multiplex ring networks, e.g. SDH/SONET H04J 3/085)}
Definition statement

This place covers:

Deals with link by link synchronization between nodes and network

synchronization.

References
Limiting references

This place does not cover:

Synchronization in general

H04J 3/06, H04L 7/00

for ring networks

H04J 3/085

Informative references

Attention is drawn to the following places, which may be of interest for search:

Time division multiplex systems

H04J 3/00

Special rules of classification

Double classification with H04J 3/00 is allowed.

with centralised control, e.g. polling
Definition statement

This place covers:

Same as for bus networks but in a physical ring network.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Bus networks with centralized control

H04L 12/403

with decentralised control
Definition statement

This place covers:

Analog to bus networks, see H04L 12/417.

References
Limiting references

This place does not cover:

Bus networks with decentralized control

H04L 12/407

with synchronous transmission, e.g. time division multiplex [TDM], slotted rings
Definition statement

This place covers:

Slotted rings; can be with fixed time slot allocation to the nodes or with access schemes for transmission access to a part of the bandwidth (slot).

with asynchronous transmission, e.g. token ring, register insertion
Definition statement

This place covers:

Nodes having the access right (token) can transmit. When finished, the token is other nodes is buffered in a register until a node has finished its own transmission. This is the main group for FDDI and Fiber Channel rings when the access method is the issue.

Ring fault isolation or reconfiguration {(for SDH/SONET ring networks H04J 3/085)}
Definition statement

This place covers:

Rings are vulnerable to faults. This subgroup contains documents dealing with recovery from faults like loop-backs or subrings when a ring systems is cut.

References
Limiting references

This place does not cover:

Fault recovery in general

H04L 41/06

Fault recovery systems for SDH/SONET(Protection Switching) ring networks

H04J 3/085

Star or tree networks
Definition statement

This place covers:

Deals with networks in a physical star or tree configuration.

In case of Ethernet repeaters or hubs, transmission is broadcast and the bus access schemes are applied (e.g. Ethernet in 10baseT).

Interconnection of networks
Definition statement

This place covers:

  • Interconnection of network segments of different types. e.g. between Fire Wire and Ethernet segments;
  • Internetworking in CEBUS, MAP/TOP, CAN and other application oriented topologies;
  • Repeaters (LAN segmentation).

This group contains general documents on internetworking in packet-switched networks.

References
Limiting references

This place does not cover:

Coupling between buses internal to a computer

G06F 13/4004

{LAN interconnection over a backbone network, e.g. Internet, Frame Relay}
Definition statement

This place covers:

  • Header group for network backbone functionality
  • SONET, SMDS, DQDB
  • XNS, SNA, CATV
  • Internet
References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Implementation or adaptation of Internet protocol [IP], of transmission control protocol [TCP] or of user datagram protocol [UDP]

H04L 69/16

{LAN interconnection over ATM networks}
Definition statement

This place covers:

  • LAN emulation
  • IP or other proprietary protocols (e.g. IPX, SNA, netBIOS, Appletalk...) over ATM. MPOA.
  • VP switching for multiplexing connections in VLAN/BVPN Connectionless support in ATM for LAN interconnection (type D service. I.364 rec., ATM Forum's scheme).
  • Some documents about remote address resolution (ARP,NHRP).
{LAN interconnection over narrowband networks, e.g. N-ISDN, PSTN, X.25}
Definition statement

This place covers:

  • Internetworking over the PSTB
  • Narrowband ISDN both using BA or PR access, Channel B or D
  • X.25 based internetworks
{LAN interconnection over a LAN backbone}
Definition statement

This place covers:

Contains mainly documents about LAN interconnection using a FDDI backbone. Do not forget that some SNA implementations use a Token Ring backbone, so if you do not find your document here have a look to the H04L 12/4604 just in case.

{LAN interconnection over a bridge based backbone}
Definition statement

This place covers:

Topology aspects: where the bridges are placed. Bridging different type 802.X LAN's. General documents on Source Routing, Spanning Tree or DLS (no much detail on how the actual routing is carried out.

References
Limiting references

This place does not cover:

Routing of packets

H04L 45/00

Informative references

Attention is drawn to the following places, which may be of interest for search:

Routing tree calculation

H04L 45/48

Layer 2 routing, e.g. Ethernet-based MAN's

H04L 45/66

Special rules of classification

Spanning tree protocol shall be classified in this group, but also possibly H04L 45/00 and subgroups when applied on a generic routing protocol that can be applied on Layer 2 as well as Layer 3 networks.

{Single bridge functionality, e.g. connection of two networks over a single bridge}
Definition statement

This place covers:

Bridge functionalities.

It covers:

  • Multistandard for heterogeneous 802.X LAN environment
  • Address learning and filtering with the suitable table lookup or CAM techniques. Address caching.
  • Internal buffer and memory management.
  • Bridges doing repeater functions or routing (Brouters)
References
Limiting references

This place does not cover:

Router functionalities or routing protocols

H04L 45/00, H04L 49/00

Informative references

Attention is drawn to the following places, which may be of interest for search:

Fast packet switching

H04L 49/00

Special rules of classification

It is difficult to determine whether to begin the search in H04L 12/462 or in H04L 12/4625. As a rule of thumb you could say that bridge/router functionality that does not require cooperation among bridges/routers, should be classified in H04L 12/4625. Therefore, network aspects that involve exchange among bridges/routers are meant to be in H04L 12/462.

{Interconnection of networks using encapsulation techniques, e.g. tunneling}
Definition statement

This place covers:

Encapsulation is the embedding of a protocol in another protocol at the same or different OSI layer. This technique is often used in a backbone to be able to deal with a plurality of end user protocols using a common transport entity.

Tunneling is a very important part of this group (e.g. L2TP).

References
Limiting references

This place does not cover:

Pseudo-wire emulation, e.g. IETF WG PWE3

H04L 45/68

Informative references

Attention is drawn to the following places, which may be of interest for search:

Point-to-point connection between the data network and the subscriber in access networks (e.g. PPPoX protocols)

H04L 12/2859

Virtual LANs

H04L 12/4641

VPN tunnels for security

H04L 63/00

Protocol conversion

H04L 69/08

{Interconnected ring systems}
Definition statement

This place covers:

  • Complex meshes of rings; Topological aspects
  • MAN, WAN ring based architectures
  • Hierarchical ring topologies
  • Streets of Manhattan, interlaced rings and similar architectures
References
Informative references

Attention is drawn to the following places, which may be of interest for search:

FDDI WANs

H04L 12/4616

{Virtual LANs, VLANs, e.g. virtual private networks [VPN] (LAN interconnection over a bridge based backbone H04L 12/462; encapsulation techniques H04L 12/4633; routing of packets H04L 45/00; packet switches H04L 49/00; virtual private networks for security H04L 63/0272)}
Definition statement

This place covers:

Virtual local area network, virtual LAN or VLAN. A group of hosts with a common set of requirements that communicate as if they were attached to the same broadcast domain, regardless of their physical location. Networks with the same attributes as a physical local area network (LAN), but that allow for end stations to be grouped together even if they are not located on the same network switch.

media16.png

References
Limiting references

This place does not cover:

LAN interconnection over a bridge based backbone

H04L 12/462

Encapsulation techniques

H04L 12/4633

Routing of packets

H04L 45/00

Packet switches

H04L 49/00

Virtual private networks for security

H04L 63/0272

{Details on frame tagging (routing of packets H04L 45/00; support for virtual LAN H04L 49/354)}
Definition statement

This place covers:

Details on tagging of a frame with VLAN information, involving mainly the use of a dedicated field for tagging a frame. When a packet enters a VLAN, a switch adds a VLAN field to the packet including a VLAN ID, the tag. Covers converting untagged frames to tagged frames. A typical VLAN tagged frame:

media17.png

References
Limiting references

This place does not cover:

Routing of packets

H04L 45/00

Routing of packets using label swapping, e.g. MPLS

H04L 45/50

Switching devices with support for virtual LAN

H04L 49/354

Special rules of classification

Multi-tagging of frames shall not be classified in H04L 12/4645, only in H04L 12/465 or the subgroups of it.

{wherein a single frame includes a plurality of VLAN tags}
Definition statement

This place covers:

Description and creation of single frames including a plurality of VLAN tags.

Frequently refers to QinQ (see IEEE standard 802.1ad) and the derivatives of this protocol. Covers tagging an already tagged packet, thereby producing a "multiple-tagged" frame, or a VLAN stack. A typical QinQ frame:

media18.jpg

References
Limiting references

This place does not cover:

Encapsulation of packets

H04L 12/4633

Special rules of classification

A document shall only be allocated this class if no relevant subgroup of this class can be found. On the other hand, different classes from this group (i.e. H04L 12/4654, H04L 12/4658, H04L 12/4662) might be assigned to a single document.

{wherein a VLAN tag represents a customer VLAN, e.g. C-Tag}
Definition statement

This place covers:

In multi-tagged frames, a VLAN tag representing a customer VLAN is a VLAN tag uniquely associated to a particular end user, subscriber or

local network entity (computer, user station).

{wherein a VLAN tag represents a service provider backbone VLAN, e.g. B-Tag, S-Tag}
Definition statement

This place covers:

Covers the outer tagging of Ethernet packets in PBB (Provider Backbone Bridge) networks, see IEEE Standard 802.1ah. A service provider backbone VLAN spans over a carrier network, not over a single LAN

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Encapsulation techniques

H04L 12/4633

{wherein a VLAN tag represents a service instance, e.g. I-SID in PBB}
Definition statement

This place covers:

Covers documents associating a VPN with a PBB and assigning an I-SID. FIG. 3 below (US2008170573) is a simplified representation of a frame format 150 for VPN data packets transmitted through a PBB tunnel. The frame format 150 includes a PBB header 152 comprised of a backbone destination address (B-DA) 154, a backbone source address (B-SA) 156, a backbone VLAN ID (B-VID) 158, and a backbone I-component service ID (I-SID) 160.

media19.jpg

Glossary of terms

In this place, the following terms or expressions are used with the meaning indicated:

PBB

Provider Backbone Bridge

{Operational details on the addition or the stripping of a tag in a frame, e.g. at a provider edge node}
Definition statement

This place covers:

Covers operations carried out on a packet header, such as adding and/or removing tags, usually according to a particular algorithm or specific structure. An emphasis is put on the operational details of adding or stripping VIDs, at a particular node, e.g. US2010226368:

media20.jpg

Special rules of classification

The mere tagging of packets or removal of tags without particular operational details shall only be classified in H04L 12/4645 or in the subgroups of H04L 12/465

{Arrangements for supporting untagged frames, e.g. port-based VLANs}
Definition statement

This place covers:

The port is assigned to a specific VLAN independent of the user or system attached to the port. All users attached to the port should be members in the same VLAN. Usually the port configuration is static. A port based VLAN switch determines the membership of a data frame by examining the configuration of the port that received the transmission.

Special rules of classification

Classes from the H04L 12/4645 subgroups and the class H04L 12/467 might be allocated to a single document only if two VLAN operational modes (i.e. tag-based VLANs and port-based VLANs) are presented in the document as part of the invention

{Dynamic sharing of VLAN information amongst network nodes (configuration of the network or of network elements H04L 41/08)}
Definition statement

This place covers:

Sharing of information between networks elements: information about the identifier, about the member status, about the port based VLAN distribution. Sometimes this layer 2 information is intended to be displayed or monitored. Even though failure recovery is not covered in this class, Layer-2 information might be dynamically shared between the elements on the network after detection of a network failure.

References
Limiting references

This place does not cover:

Failure recovery

H04L 41/06

Configuration of the network, or of network elements

H04L 41/08

{Arrangements for the registration or de-registration of VLAN attribute values, e.g. VLAN identifiers, port VLAN membership}
Definition statement

This place covers:

Registration or de-registration of VLAN memberships. Also includes removing, discovering and identifying VLAN members. Covers also the exchange of messages for modifying an entry in a mapping table for switches supporting port-based VLANs.

References
Limiting references

This place does not cover:

Configuration of switching devices

H04L 12/4641

{characterized by the protocol used}
Definition statement

This place covers:

Details on a specific standardized or proprietary protocol for maintaining a VLAN, for registering, de-registering VLAN members

References
Limiting references

This place does not cover:

Group membership management

H04L 41/0893

Special rules of classification

Only for defining particular routines, packets types or format when maintaining VLANs. Can include extensions or modifications of an existing protocol

{MVRP [multiple VLAN registration protocol]}
Definition statement

This place covers:

A commonly-used VLAN registration protocol generic framework defined by the IEEE 802.1ak revision to the IEEE 802.1Q standard.

{GVRP [GARP VLAN registration protocol]}
Definition statement

This place covers:

This is a standards-based Layer 2 network protocol, for automatic configuration of VLAN information on switches. It was defined in the 802.1ak amendment to 802.1Q-2005.

Glossary of terms

In this place, the following terms or expressions are used with the meaning indicated:

GARP

Generic Attribute Registration Protocol

Synonyms and Keywords

In patent documents, the following abbreviations are often used:

MVRP

Multiple VLAN Registration Protocol

{VTP [VLAN trunking protocol]}
Definition statement

This place covers:

VTP is a proprietary protocol that propagates the definitions of Virtual Local Area Networks (VLAN) on a whole local area network.

Store-and-forward switching systems  (packet switching systems H04L 45/00, H04L 47/00)
Definition statement

This place covers:

Systems in which information is sent to an intermediate station where it is kept and sent at a later time to the final destination or to another intermediate station.

References
Limiting references

This place does not cover:

Routing or path finding of packets in data switching networks

H04L 45/00

Traffic control in data switching networks

H04L 47/00

{Packet switching systems}
Definition statement

This place covers:

Basic functionality of packet switching networks. Namely: routing, flow control, admission control, switching architectures and other general issues on packetized data handling.

References
Limiting references

This place does not cover:

Interprocessor communication

G06F 15/163

Packet based communication in satellite networks

H04B 7/185

Networks specially adapted for the exchange of pictorial information

H04N 7/00

Application-oriented references

Examples of places where the subject matter of this place is covered when specially adapted, used for a particular purpose, or incorporated in a larger system:

Arrangements for packet switching specially adapted for wireless networks

H04W

Informative references

Attention is drawn to the following places, which may be of interest for search:

Error detection or correction

H04L 1/00

Packet multiplexing

H04J

Synonyms and Keywords

In patent documents, the following abbreviations are often used:

ATM

Asynchronous Transfer Mode

TCP/IP

Transmission Control Protocol/Internet Protocol

{Transfer mode dependent, e.g. ATM}
Definition statement

This place covers:

Asynchronous Transfer Mode(ATM) technical aspects.

References
Limiting references

This place does not cover:

Routing in wireless networks

H04W 40/00

Details of the apparatus or circuits covered by groups H04L 15/00 or H04L 17/00
References
Limiting references

This place does not cover:

Apparatus or local circuits for transmitting or receiving dot-and-dash codes

H04L 15/00

Apparatus or local circuits for transmitting or receiving codes wherein each character is represented by the same number of equal-length code elements

H04L 17/00

Driving mechanisms; Clutches
References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Couplings for transmitting rotation; clutches

F16D

Spread spectrum techniques using chirp

H04B 2001/6912

Electronic distributors
References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Electronic switching or gating

H03K 17/00

Apparatus or local circuits for transmitting or receiving dot-and-dash codes, e.g. Morse code (teaching apparatus therefor G09B; telegraph tapping keys H01H 21/86)
References
Limiting references

This place does not cover:

Educational or demonstration appliances; appliances for teaching or communicating with, the blind, deaf or mute; models; planetaria; globes; maps; diagrams

G09B

Switches with abutting contact carried by operating part

H01H 21/86

Informative references

Attention is drawn to the following places, which may be of interest for search:

Having a plurality of operating members associated with different sets of contacts

H01H 13/70

Characterised by the way in which the control signal is generated

H03K 17/94

Coding in connection with keyboards or like devices

H03M 11/00

Apparatus or local circuits for transmitting or receiving codes wherein each character is represented by the same number of equal-length code elements, e.g. Baudot code
References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Having a plurality of operating members associated with different sets of contacts

H01H 13/70

Characterised by the way in which the control signal is generated

H03K 17/94

Coding in connection with keyboards or like devices

H03M 11/00

Apparatus or local circuits for systems other than those covered by groups H04L 15/00 - H04L 21/00
References
Limiting references

This place does not cover:

Apparatus or local circuits for transmitting or receiving dot-and-dash codes

H04L 15/00 - H04L 21/00

adapted for orthogonal signalling
Definition statement

This place covers:

Code Shift Keying and CCK (Complementary Code Keying).

The generation of sequences, like orthogonal CAZAC, Zadoff-Chu or Generalized Chirp sequences that are used for signalling purposes.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Codes types for Code Division Multiplex systems (CDMA)

H04J 13/0007

Generation of orthogonal codes for CDMA

H04J 13/12

Baseband systems
Definition statement

This place covers:

Baseband aspects of digital data transmission.

Arrangements for supplying electrical power along data transmission lines.

Channel estimation techniques.

Arrangements for detecting the data rate of an incoming signal.

Arrangements for coupling to transmission lines.

Line equalizers (digital).

Shaping networks in transmitter or receiver.

Digital equalizers: structure and adaptation algorithms.

Arrangements involving sequence estimation techniques.

Electric or magnetic storage of signals before transmitting or retransmitting for changing the transmission rate.

Decision circuits providing symbol by symbol detection; DC level restoring means; Bias distortion correction.

Modifications for reducing interference in line transmission.

Digital repeater/relay circuits.

Line codes.

Pulse width modulation; pulse position modulation.

References
Limiting references

This place does not cover:

Error correction coding

H04L 1/004

Arrangements for synchronising receiver with transmitter

H04L 7/00

Joint detection techniques in CDMA

H04B1/70105

Interference related aspects of DSSS

H04B 1/7097

Systems for transmitting signals via power distribution lines

H04B 3/54

Details on optical domain processing

H04B 10/516

Informative references

Attention is drawn to the following places, which may be of interest for search:

Bus networks

H04L 12/40

Digital adaptive filters

H03H 21/0012

Matched filters

H03H 21/0018

Kalman filters

H03H 21/003

Circuits in general for handling pulses

H03K

Coupling arrangements in general

H03K 19/0175

Conversion to or from representation by pulses

H03M 5/00

Coding in general

H03M 13/00

Details in line transmission systems in general

H04B 3/02

Echo cancellation

H04B 3/20

Reducing cross-talking

H04B 3/32

MIMO diversity systems

H04B 7/0413

Feedback content

H04B 7/0621

Wireless repeaters in general

H04B 7/15

Modelling the propagation channel

H04B 17/391

Interference aspects in orthogonal multiplex systems (i.e. using Walsh codes)

H04J 11/0023

Special rules of classification

The groups under H04L 2025/0335 classify the type of signal the equalizer is intended for.

The groups under H04L 2025/03433 provide further details on the equalizer structure implementation.

The groups under H04L 2025/03592 deal with details of the adaptation algorithms for equalisation.

The groups under H04L 2025/03777 provide details on signalling.

Glossary of terms

In this place, the following terms or expressions are used with the meaning indicated:

DFE

Decision Feedback Equaliser

SVD

Singular Value Decomposition

FIR

Finite Impulse Response

FDE

Frequency Domain Equalizer

GPRS

General Packet Radio Service

ICI

Inter-Carrier Interference

ISI

Inter-Symbol Interference

LLR

Log-Likelihood Ratio

LMMSE

Linear Minimum Mean Squared Error

LMS

Least Mean Square

LS

Least Squares

MAP

Maximum A-posteriori Probability

MLD

Maximum Likelihood Detector

MMSE

Minimum Mean Squared Error

RLS

Recursive Least Square

Synonyms and Keywords

In patent documents "pilot signals" can be called sometimes "Reference signals", "Sounding signals" or "Training signals".

Details {; arrangements for supplying electrical power along data transmission lines (systems for transmitting signals via power distribution lines H04B 3/54)}
References
Limiting references

This place does not cover:

Systems for transmitting signals via power distribution lines

H04B 3/54

Informative references

Attention is drawn to the following places, which may be of interest for search:

Circuits in general for handling pulses

H03K

In line transmission systems in general

H04B 3/02

{of each channel individually}
Special rules of classification

This subgroup should not be used for classifying. Instead H04L 25/0204 should be given.

{of the composite channel}
Special rules of classification

This subgroup should not be used for classifying. Instead H04L 25/0204 should be given.

{of impulse response}
Definition statement

This place covers:

The delay spread estimation.

{sounding signals per se}
Definition statement

This place covers:

The structure of the sounding signals or the pilot pattern. For details of the allocation of the sounding signals: H04L 5/0048.

{with direct estimation from sounding signals}
Definition statement

This place covers:

This group answer the question of how the sounding signals are used to derive an estimation. For example, by averaging.

{with extension to other symbols}
Definition statement

This place covers:

Use of data (in addition to the sounding signals) for channel estimation

{using estimation of the other symbols}
Definition statement

This place covers:

Iterative channel estimation for the same symbol, for example the EM (maximum expectation).

{using blind estimation}
Definition statement

This place covers:

Using only data per se.

{with factorisation}
Definition statement

This place covers:

For example: Cholesky, LU.

{Eigen-space methods}
Definition statement

This place covers:

Singular value decomposition, SVD.

{using least-mean-square [LMS] method}
Definition statement

This place covers:

All iterative algorithm (not for the same symbol), for example: RLS.

{Arrangements for coupling transmitters, receivers or transceivers to transmission lines; Line drivers (duplexing arrangements H04L 5/14)}
References
Limiting references

This place does not cover:

Line drivers (duplexing arrangements

H04L 5/14

Special rules of classification

This group should not be used. Subject-matter is classified under H04L 25/0264.

{Arrangements for detecting the data rate of an incoming signal}
Definition statement

This place covers:

This involves frequency estimation or detection, but not synchronisation.

{Arrangements for impedance matching}
Definition statement

This place covers:

The arrangements are at either end.

{Arrangements specific to the transmitter end}
Definition statement

This place covers:

How to couple the driver to the transmission line or how to configure the driver.

{the shape being matched to the transmission line (pre-equalisation per se H04L 25/03343)}
Definition statement

This place covers:

Implies some knowledge of the actual line, although it might be rather vague, such as "this is 100 m long". Thus, the coupling provides the pre-emphasis, otherwise, if it is not in the coupling, H04L 25/03885 is the proper place to classify.

References
Limiting references

This place does not cover:

the shape being matched to the transmission line (pre-equalisation per se

H04L 25/03343

Shaping networks in transmitter or receiver, e.g. adaptive shaping networks
Definition statement

This place covers:

Shaping networks in transmitter or receiver, e.g. adaptive shaping networks, receivers or arrangements for processing base band signals.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Impedance networks, e.g. resonant circuits; resonators

H03H

{Arrangements for removing intersymbol interference}
Definition statement

This place covers:

The subgroups under H04L 25/03006 cover digital equalisation and detection techniques. Digital equalisers not only try to make the channel flat and remove ISI, but they also implement detection and decision.

{with a recursive structure (H04L 25/03031 takes precedence)}
Definition statement

This place covers:

For example, DFE equalisers.

{Arrangements involving sequence estimation techniques}
Definition statement

This place covers:

MLSE techniques, and in general the estimation of a sequence of symbols (not just one symbol).

In the case of multiuser environment, it covers the estimation of the different users.

{Joint sequence estimation and interference removal (joint detection of several desired signals H04L 25/03331)}
Definition statement

This place covers:

The cases where desired user is estimated and the other users are seen as interferences, such that their estimation is removed (for example, by subtraction).

References
Limiting references

This place does not cover:

Joint sequence estimation and interference removal (joint detection of several desired signals

H04L 25/03331

{Arrangements at the transmitter end}
Definition statement

This place covers:

Pre-equalisation.

Pre-coding for MIMO channels can be seen as a pre-equaliser or as a beam-former.

The selection of codebook or precoding matrix for MIMO diversity systems is classified under H04B 7/0456, while the design of the codebook matrices is classified under H04L 25/03898.

{transmission using multiple-input and multiple-output channels}
Definition statement

This place covers:

Not limited to radio systems but also covers the case of cross-talk between cables as a MIMO system.

{not time-recursive}
Definition statement

This place covers:

For example: FFF (feed forward filter).

{Transmission of equaliser coefficients}
Definition statement

This place covers:

The cases of the feedback of codebook index to be able to choose a precoding matrix at the transmitter.

Dc level restoring means; Bias distortion correction {; Decision circuits providing symbol by symbol detection}
References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Detection of unique words or other known elements

H04L 7/00, H04J 3/0602

{providing soft decisions, i.e. decisions together with an estimate of reliability (H04L 25/068 and H04L 25/069 take precedence; sequence estimation techniques H04L 25/03178)}
Definition statement

This place covers:

When the soft decisions are part of a sequence estimation, then the place to classify is H04L 25/03318, otherwise, when the soft decisions are symbol by symbol is classified in H04L 25/067.

References
Limiting references

This place does not cover:

Sequence estimation techniques

H04L 25/03178

By sampling faster than the nominal bit rate

H04L 25/068

By detecting edges or zero crossings

H04L 25/069

Compensating for variations in line balance
References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Balancing during the coupling of signals

H04L 25/0282

Compensating for variations in line impedance
References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Impedance matching in coupling arrangements

H04L 25/0278

Channel dividing arrangements {, i.e. in which a single bit stream is divided between several baseband channels and reassembled at the receiver}
Definition statement

This place covers:

The parallel transmission of a single bit stream and the reassembling (skew compensation) of all the content of the parallel channels at the receiver in order to retrieve the single bit stream.

Repeaters for converting two wires to four wires; Repeaters for converting single current to double current
Definition statement

This place covers:

Wired digital repeaters. For wireless repeaters see classes under H04B 7/15.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Repeaters for converting two wires to four wires

H04B

Transmitting circuits; Receiving circuits {(repeater circuits, relay circuits H04L 25/20)}
References
Limiting references

This place does not cover:

Repeater circuits, relay circuits

H04L 25/20

Informative references

Attention is drawn to the following places, which may be of interest for search:

Arrangements for synchronising receiver with transmitter

H04L 7/00

Using the transitions of the received signal to control the phase of the synchronising-signal-generating means

H04L 7/033

Transmitting and receiving encryption devices synchronised or initially set up in a particular manner

H04L 9/12

using electronic distributors
References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Electronic distributors in general

H03K 17/00

using code conversion at the transmitter; using predistortion; using insertion of idle bits for obtaining a desired frequency spectrum; using three or more amplitude levels {; Baseband coding techniques specific to data transmission systems (spectral shaping H04L 25/03828)}
References
Limiting references

This place does not cover:

Spectral shaping

H04L 25/03828

Informative references

Attention is drawn to the following places, which may be of interest for search:

Preprocessing of received signal for synchronisation, e.g. by code conversion

H04L 7/0087

Coding, decoding or code conversion, in general

H03M

{using self-synchronising codes, e.g. split-phase codes}
Definition statement

This place covers:

For example: Manchester code; Biphase space or mark code (e.g. double frequency code).

{using multilevel codes}
Definition statement

This place covers:

For example: PAM with more than 2 levels.

{using levels matched to the quantisation levels of the channel}
Definition statement

This place covers:

PCM modems V.90.

by correlative coding, e.g. partial response coding or echo modulation coding {transmitters and receivers for partial response systems (transversal equalizers at the transmitter end H04L 25/03343)}
Definition statement

This place covers:

For example: Tolimson-Harashima precoding, Trellis precoding, GPRS.

References
Limiting references

This place does not cover:

Transmitters and receivers for partial response systems equalizers at the transmitter end

H04L 25/03343

Informative references

Attention is drawn to the following places, which may be of interest for search:

Response systems (transversal equalizers

H04L 25/03

Partial response continuous phase modulation systems

H04L 27/18

Modulated-carrier systems
Definition statement

This place covers:

Modulated-carrier systems.

Passband aspects of data transmission, e.g. modulating and demodulating, arrangements for provision and recovery of carriers.

The most fundamental digital modulation techniques: ASK, FSK, PSK and QAM.

Multicarrier modulation systems.

The modulated carrier systems covered in this groups are independent on the type of physical signal, i.e. the signal can be audio, RF, optical,..., but the signals must be digital.

Relationships with other classification places

When the multiple access scheme relies on the use of multicarrier signals,

and if what is important is how the signal is modulated/demodulated, or "hardware" aspects in the transmitter or the receiver to produce or recover (like synchronisation) such signal or aspects related to the peak power reduction, then the classes under H04L 27/2601 are relevant. Otherwise, to indicate that the signal involved is, for example, an OFDM signal, then the class under H04L 5/0007 is used instead.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Block-coded modulation

H04L 1/0058

Trellis-coded modulation

H04L 1/006

Arrangements affording multiple use of the transmission path

H04L 5/00

Modulated-carrier systems (code shift keying in combination with frequency multiplexing

H04L 5/06

Simultaneous bidirectional transmission of ac signals

H04L 5/143

Code Shift Keying; CCK (complementary code keying)

H04L 23/02

Pulse width modulation; Pulse position modulation

H04L 25/4902

Pulse amplitude modulation

H04L 25/4917

CORDIC

G06F 7/5446

Modulator circuits in general (analogue modulators)

H03C

Demodulator circuits in general (analogue demodulators)

H03D

Modifications in amplifiers to reduce non-linear distortions, by pre-distortion

H03F 1/3241

Pulse Amplitude modulation, i.e. PAM

H03K 7/02

Delta modulation

H03M 3/02

Details on optical domain processing

H04B 10/516

Polarisation shift keying

H04B 14/008

Transmission of data during the active part of a television frame

H04N 7/025

Glossary of terms

In this place, the following terms or expressions are used with the meaning indicated:

ASK

Amplitude Shift Keying

CPM

Continuous Phase Modulation

FSK

Frequency Shift Keying

OOK

On-Off Keying

PSK

Phase Shift Keying

DPSK

Differential Phase Shift Keying

QAM

Quadrature Amplitude Modulation

Synonyms and Keywords

In patent documents the following expression "multiresolution systems" is often used as synonym of non-uniform or asymmetric or layered modulation or hierarchical modulation or superposed modulation.

Equalisers {(baseband equalizers at the transmitter end H04L 25/03343; in analogue transmission systems H04B 3/04, H04B 7/005)}
References
Limiting references

This place does not cover:

Baseband equalizers at the transmitter

H04L 25/03343

In analogue transmission systems

H04B 3/04, H04B 7/005

Informative references

Attention is drawn to the following places, which may be of interest for search:

Control of amplification

H03G

Demodulator circuits; Receiver circuits
References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Demodulation of amplitude-modulated pulses

H03K 9/02

Frequency-modulated carrier systems, i.e. using frequency-shift keying (H04L 27/32 takes precedence)
References
Limiting references

This place does not cover:

Carrier systems in general comprising amplitude-modulated carrier systems, and phase-modulated carrier systems

H04L 27/32

Informative references

Attention is drawn to the following places, which may be of interest for search:

The signals being represented by different frequencies

H04L 5/06

The synchronisation signals differing from the information signals in amplitude, polarity, or frequency

H04L 7/06

Frequency multiplication

H04L 2027/0048

Continuous phase systems

H04L 27/18

{Chirp modulation (for spread spectrum techniques H04B 1/69)}
References
Limiting references

This place does not cover:

Spread spectrum techniques

H04B 1/69

Informative references

Attention is drawn to the following places, which may be of interest for search:

Spread spectrum techniques using chirp

H04B 2001/6912

Modulator circuits; Transmitter circuits
References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Continuous phase modulation

H04L 27/20

Frequency or rate pulse modulation

H03K 7/06

Demodulator circuits; Receiver circuits
References
Informative references

Attention is drawn to the following places, which may be of interest for search:

For continuous phase modulation systems

H04L 27/22

Demodulation of frequency- or rate-modulated pulses

H03K 9/06

Modulator circuits; Transmitter circuits
References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Position modulation

H03K 7/04

Demodulator circuits; Receiver circuits
References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Demodulation of position-modulated pulses

H03K 9/04

Systems using multi-frequency codes (H04L 27/32 takes precedence)
Definition statement

This place covers:

All techniques related to the multiple carriers processing of electrical signals (at the transmitter and receiver), to the structure of such signals (pilot signals, guard interval), and problems related to the frequency domain processing of such signals (Peak to Average Power Ratio PAPR).

Example of systems covered: OFDM, OFDMA, SC-FDMA, IFDMA, LTE, DVB, DSL, Optical OFDM ...

Practically the coverage of this subgroup in term of features is:

  • within a transmitter, it starts at the serial to parallel transformation of the data and ends after the IFFT (or any other frequency domain to time domain converter) or post-PAPR processing, and includes the PAPR processing, the pilot insertion, and if present the DFT precoding of the data (for SC-FDMA systems).
  • within a receiver, it starts at the FFT (or any other time domain to frequency domain converter) and includes the synchronisation arrangements (time, frequency).
References
Limiting references

This place does not cover:

Resource allocation techniques

H04L 5/00

Bit loading of the subcarriers for OFDM(A) systems

H04L 5/0046

Pilot allocation for OFDM(A) systems

H04L 5/0048

Techniques like MC-CDMA involving code and frequency multiplexing

H04L 5/026, H04L 5/0021

Carrier systems

H04L 27/32

Informative references

Attention is drawn to the following places, which may be of interest for search:

Channel estimation techniques

H04L 25/0202

Interference cancellation techniques (Inter Carrier Interference, multiusers)

H04L 25/03006

Pulse shaping

H04L 25/03834

Details of Fourier transforms

G06F 17/141

Optical transmitters

H04B 10/50

Higher Layer (network, routing) techniques

H04W

{Multicarrier modulation systems}
Special rules of classification

Although mentioned as modulation, it can of course be interpreted as multiplexing depending on the way the processing is interpreted. In a way it is a modulation since the main carrier signal is mixed with a modulating signal being the output of the IFFT after cyclic prefix addition. However it is also multiplexing since data being either from one user or from multiple users are orthogonally mapped to the subcarriers.

This group is generally given to aspects not covered by any of the following lower subgroups, or to documents where OFDM is a secondary technical aspect.

{Signal structure}
Special rules of classification

The two main aspects under this group are the cyclic prefix classified under H04L 27/2605 and the pilot structure under H04L 27/261.

Basically documents classified here have their main feature in the mapping of particular data to the subcarriers or properties of the resultant OFDM time domain signal after IFFT, rather than particular means for processing the signal.

{Multiresolution systems (by means of multiresolution subcarriers H04L 27/183, H04L 27/3488)}
Definition statement

This place covers:

Different constellations (modulations) used on the subcarrier. For the allocation aspect (i.e. waterfilling for instance), see H04L 5/0044.

References
Limiting references

This place does not cover:

Multiresolution modulation methods

H04L 27/183, H04L 27/3488

{Symbol extensions, e.g. Zero Tail, Unique Word [UW]}
References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Details of impulse response

H04L 25/0212

Symbol synchronization (locating the FFT window within a useful data portion + guard period)

H04L 27/2665

Delay profiles

H04B 17/364

Special rules of classification

Most of the OFDM systems (except OQAM OFDM) use a cyclic extension added in time domain after each symbol in order to capture all multipath components that would result otherwise in Inter Symbol Interference (H04L 25/03006). Documents classified here either use a particular extension (adaptive or with a specific pattern) or provide for a specific processing of this extension.

Synonyms and Keywords

In patent documents, the following words/expressions are often used as synonyms:

  • "Symbol Extension", "Cyclic Prefix/Postfix/Suffix/Extension" and "Guard Period/Interval"
{Cyclic extensions}
Special rules of classification

The Guard Period is a repetition of a portion of the useful data segment of the symbol transmitted.

{Structure of the reference signals}
Definition statement

This place covers:

Properties of the reference sequences used as preamble or pilot sequence.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Sounding signals for channel estimation

H04L 25/0226

Linked to code properties

H04J 13/00

CAZAC sequences

H04J 13/0055

{Peak power aspects}
Special rules of classification

The Inverse Fourier transform at the transmitter transforms modulated symbols on each subcarrier, modulated by usual constellation patterns (QPSK, QAM), to time domain symbols presenting high peak to average power ratio. This problem is a recurrent problem in OFDM systems.

This high PAPR creates linearity problems at the following power amplifiers and must be remedied for in the time domain (i.e. after the IFFT, for instance by clipping) or in the frequency domain (i.e. before the IFFT) using iteration and feedback loop (using empty subcarrier, constellation extension ...).

When none of the following subclasses matches the technique used in the document, this class H04L 27/2614 has to be given.

Synonyms and Keywords

In patent documents, the following words/expressions are often used as synonyms:

  • "peak to average power ratio", "PAPR " and "Crest factor"
{Reduction thereof using coding}
Special rules of classification

Through coding the series of bits before the modulation and the serial to parallel transformation, the situation where all modulated symbols on each subcarrier have the same phase thus generating the highest power is avoided. (See Jones and Wilkinson: "Block coding scheme for reduction of peak-to-average envelope power ratio of multicarrier transmission systems", 1994).

{Reduction thereof using auxiliary subcarriers}
Definition statement

This place covers:

For instance: Tone Injection or Tone Reservation. A subset of subcarriers is used for generating a PAPR reduction signal c added to the remaining signal transmitted.

{Reduction thereof using phase offsets between subcarriers}
Definition statement

This place covers:

One of the most active subfields of PAPR reduction: Encompasses techniques like Selective Mapping (SLM) or Partial Transmission Sequence (PTS). Considering N subcarriers, SLM performs M multiple parallel N point IFFTs, each using a different N-phase vector (one phase value applied to each subcarrier) and selects out of the M outputs the resulting time domain OFDM with the lowest PAPR value. PTS divides the N subcarriers in V disjoint subcarriers subsets, multiplies each by a phase value and performs V partial IFFT before adding the resulting V outputs producing the OFDM symbol to be sent.

media22.png

From Tao Jiang & al. "An Overview: Peak-to-Average Power Ratio Reduction Techniques for OFDM Signals"

{Reduction thereof by clipping}
Definition statement

This place covers:

Large field: Can happen in time domain (usual understanding where the parts outside the allowed power region are filtered or clipped out) but also in frequency domain (modulated symbols on each subcarrier are moved, see Active Constellation Extension). Can consist in decreasing higher power samples (by filtering or clipping) or enhancing low power samples (see nonlinear companding transforms using for instance μ-law companding from speech processing). Modify the dynamics of the signal.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Clipping in the frequency domain of the modulated symbols

H04L 27/3411

{by soft clipping}
Definition statement

This place covers:

Based on Quantization aspects (linked to digital to analog conversion as well), see for instance the nonlinear companding method.

{Arrangements specific to the transmitter only}
Definition statement

This place covers:

As depicted below, the features covered under this class extend from the serial to parallel conversion to the Guard Interval insertion and/or PAPR reduction block.

media23.png

{Modulators}
Definition statement

This place covers:

This part concerns the frequency domain to time domain conversion using either the classical Fourier transform, the filter bank approach or direct modulation of individual subcarriers.

{Inverse Fourier transform modulators, e.g. inverse fast Fourier transform [IFFT] or inverse discrete Fourier transform [IDFT] modulators (H04L 27/2634 takes precedence)}
References
Limiting references

This place does not cover:

Inverse Fourier transform modulators or inverse discrete Fourier transform modulators

H04L 27/2634

{with polyphase implementation}
Definition statement

This place covers:

Filter bank applications.

Synonyms and Keywords

In patent documents, the following abbreviations are often used:

FMT

Filtered Multitone

{using partial FFTs}
Definition statement

This place covers:

Less subcarriers processed than the actual number of subcarriers to be transmitted.

{Inverse fast Fourier transform [IFFT] or inverse discrete Fourier transform [IDFT] modulators in combination with other circuits for modulation}
References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Modulation circuits in general (Amplitude modulation)

H04L 27/02

Frequency modulation

H04L 27/10

Phase modulation

H04L 27/18

Combined modulation, like QAM

H04L 27/32

DFT and FFT computation methods and devices in general

G06F 17/141

{with FFT or DFT modulators, e.g. standard single-carrier frequency-division multiple access [SC-FDMA] transmitter or DFT spread orthogonal frequency division multiplexing [DFT-SOFDM]}
Definition statement

This place covers:

A DFT precoding of the symbols to be transmitted is performed prior to the IDFT. This gives good PAPR properties to the resulting signal.

media24.png

Conventional SC-FDMA Transmitter

{with direct modulation of individual subcarriers}
Definition statement

This place covers:

The frequency domain to time domain conversion is not performed using any inverse Fourier transform.

{Modulators using other transforms, e.g. discrete cosine transforms, Orthogonal Time Frequency and Space [OTFS] or hermetic transforms}
References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Details on Discrete Cosine Transform

G06F 17/147

{Pulse-shaped multi-carrier, i.e. not using rectangular window}
Definition statement

This place covers:

Loss of orthogonality between the carriers due to the use of synthesis and analysis filter banks instead of the rectangular pulse of OFDM. Advantages: More freedom for the choice of pulses which can be more confined in time and frequency. No guard interval needed. Often combined with the use of higher density of basis functions (twice if only orthogonality in real domain should be ensured) like OQAM scheme.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Sounding signals for channel estimation

H04L 25/03834

{Wavelet transform modulators (wavelet-division H04L 5/0008)}
Definition statement

This place covers:

Discrete Wavelet Multitone, Wavelet based multicarrier ...

References
Limiting references

This place does not cover:

Using Wavelet for dividing the transmission path

H04L 5/0008

Informative references

Attention is drawn to the following places, which may be of interest for search:

Wavelet transforms per se

H04L 27/0004

{using symbol repetition, e.g. time domain realization of distributed FDMA}
Definition statement

This place covers:

For the uplink of some standards.

{with oversampling}
Definition statement

This place covers:

More than one sample per subcarrier. Oversampling OFDM.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Filtered Multitone

H04L 27/264

{using feedback from receiver for adjusting OFDM transmission parameters, e.g. transmission timing or guard interval length}
References
Informative references

Attention is drawn to the following places, which may be of interest for search:

{Arrangements specific to the receiver only (equalisation H04L 27/01)}
Definition statement

This place covers:

This is the mirror part to H04L 27/2626.

media25.png

From US2007153673

References
Limiting references

This place does not cover:

Equalisation

H04L 27/01

Informative references

Attention is drawn to the following places, which may be of interest for search:

Arrangements for removing intersymbol interference

H04L 25/03006

{Synchronisation arrangements}
Definition statement

This place covers:

The synchronisation of multicarrier signals received implies a three-step synchronisation: a symbol synchronisation, a frequency synchronisation and a frame synchronisation.

Reference Article: "Robust Frequency and Timing Synchronization for OFDM"; Timothy M. Schmidl and Donald C. Cox, Fellow, 1997, IEEE

Also linked to Primary Synchronisation Signal (PSCH) and Secondary Synchronisation Signal (SSCH) in LTE.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Synchronisation at the physical level not specific to multicarrier systems

H04L 7/00

Carrier Synchronisation not specific to multicarrier systems

H04L 27/0014

Determination of the cell ID (cell search)

H04J 11/0069

Synchronisation protocols at higher layers

H04W 56/00

{Frame synchronisation, e.g. packet synchronisation, time division duplex [TDD] switching point detection or subframe synchronisation}
Definition statement

This place covers:

Frame synchronisation is generally achieved by time domain correlation using a repetition preamble. Technique is similar as that for achieving symbol synchronisation.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Preamble design

H04L 27/2613

Symbol synchronisation

H04L 27/2662

{Carrier synchronisation}
Definition statement

This place covers:

Carrier Synchronisation in OFDM systems often consists in a first round for identifying an offset corresponding to an integer number of subcarrier spacings (coarse synchronisation), and a second round identifying the fractional subcarrier spacing offset (i.e. less than a subcarrier spacing).

Special rules of classification

In H04L 27/2657, only the cases not decomposing the synchronisation in these coarse and fine steps should be classified. Otherwise the subgroups H04L 27/2659 and H04L 27/266 should be used.

Synonyms and Keywords

In patent documents the following expressions "frequency offset", "frequency shift", "frequency drift", "frequency error", "frequency correction", "carrier recovery" are often used in relation with this subgroup.

{Coarse or integer frequency offset determination and synchronisation}
Definition statement

This place covers:

An integer subcarrier spacing frequency offset causes at the receiver a shift of the subcarriers in the frequency domain.

Coarse frequency offset determination is often performed in the frequency domain: It consists in identifying the amount of subcarrier shifts by correlating the received signal after FFT with a reference signal.

{Fine or fractional frequency offset determination and synchronisation}
Definition statement

This place covers:

A fractional subcarrier spacing offset causes at the receiver an attenuation of each subcarrier symbol in the frequency domain.

Usually this fractional offset is identified by autocorrelating the received preamble in the time domain.

{Symbol synchronisation}
Definition statement

This place covers:

The same distinction between coarse and fine synchronisation as for the frequency synchronisation applies.

The symbol boundaries replace the carrier spacing: While the coarse symbol synchronisation will align the received symbol stream with a reference time, the fine symbol synchronisation mainly consists of synchronisation within the symbol boundaries (i.e. including the Guard Interval) and the best positioning of the FFT window within these boundaries.

Special rules of classification

As for frequency synchronisation, this class H04L 27/2662 should only be allocated to cases not decomposing the synchronisation in these coarse and fine steps. Otherwise the subgroups H04L 27/2663 and H04L 27/2665 should be used.

{Coarse synchronisation, e.g. by correlation}
Definition statement

This place covers:

Generally coarse symbol synchronisation is achieved by autocorrelation in the time domain of the preamble sequence.

{Fine synchronisation, e.g. by positioning the FFT window}
Definition statement

This place covers:

A FFT window of length corresponding to the useful symbol part must be positioned within the wider part including the Guard Interval. The ideal FFT location minimizes Inter Symbol Interference (ISI) and ensures the highest desired signal energy captured.

{Acquisition of further OFDM parameters, e.g. bandwidth, subcarrier spacing, or guard interval length}
Definition statement

This place covers:

In some systems using OFDM, transmission parameters like the Guard Interval length, the carrier spacing and/or bandwidth are variable or unknown to the receiver and thus have to be determined at the receiver (without any control channel). This class covers the different algorithms and methods to determine these parameters at the receiver.

References
Limiting references

This place does not cover:

Allocation of subcarriers

H04L 5/003, H04W 72/04

{Details of algorithms}
Definition statement

This place covers:

This class has been foreseen as a complementary class to the synchronisation classes above. It aims at further describing the synchronisation algorithm performed. Multiple classes may be allocated to describe the algorithm as precisely as possible.

{characterised by the domain of operation}
Definition statement

This place covers:

This first subclass concerns the domain (time or frequency) in which the algorithm takes place. For mixed domain (files where parts of the algorithm takes place in time domain and other parts in frequency domain), this class H04L 27/2669 should be allocated.

{Time domain}
Definition statement

This place covers:

The main algorithm of the invention has its essential steps performed in time domain.

{Frequency domain}
Definition statement

This place covers:

The main algorithm of the invention has its essential steps performed in frequency domain.

{characterised by synchronisation parameters}
Definition statement

This place covers:

This subclass should be allocated to describe which part of the received signal is used for achieving synchronisation: This can be known symbols (a preamble or pilot symbols), or it can be blind by using only unknown symbols (the decision of these symbols or their cyclic extension, or the presence of a repetition pattern).

{Pilot or known symbols}
References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Allocation of pilot signals

H04L 5/0048

Structure of pilot symbols

H04L 27/2613

Cell search in orthogonal multiplex systems

H04J 11/0069

Special rules of classification

Classification here should take place when the synchronisation algorithm of the document uses known symbols and their location at the receiver to achieve synchronisation. The value of these symbols is known.

{Blind, i.e. without using known symbols}
Definition statement

This place covers:

In this case, the algorithm does not use any known symbols (the value of these symbols and their location is not known in advance).

{using cyclostationarities, e.g. cyclic prefix or postfix}
Definition statement

This place covers:

The Guard Interval structure (when the Guard Interval consists of a cyclic repetition of the useful symbol part, see H04L 27/2607) or any other cyclostationarity of the received signal is used for achieving synchronisation.

The use of a repetition pattern (where instead of a preamble, a data symbol is sent twice, and the receiver uses only the location and the fact that repetition occurred) is considered as being blind and belongs to this class since it uses a kind of cyclostationarity in the received signal.

{Decision-aided}
Definition statement

This place covers:

The algorithm has a feedback loop where decision on received symbols are used to achieve synchronisation.

{characterised by constraints}
Definition statement

This place covers:

The constraints given to the algorithm or in other words, the advantage of the algorithm versus conventional algorithms.

{Precision}
Definition statement

This place covers:

The algorithm of the document achieves a better precision (in time or frequency) than conventional algorithms.

{Complexity}
Definition statement

This place covers:

The algorithm of the document has a lesser complexity than conventional algorithms.

{Speed of convergence}
Definition statement

This place covers:

The algorithm of the document reaches synchronisation more quickly than conventional algorithms.

{Range of frequencies or delays tested}
Definition statement

This place covers:

The algorithm of the document has a wider range of frequencies or delays tested than conventional algorithms.

{Resistance to perturbation, e.g. noise, interference or fading}
Definition statement

This place covers:

The algorithm of the document is more resistant to such perturbations or errors than conventional algorithms.

{Link with other circuits, i.e. special connections between synchronisation arrangements and other circuits for achieving synchronisation}
Definition statement

This place covers:

This particular subgroup applies when a synergistic effect is present between the synchronisation arrangement and any other circuit in the course of the synchronisation process (example: Locating the FFT window is often associated with particular peak tracking arrangements for channel estimation).

{involving interference determination or cancellation}
Definition statement

This place covers:

For the cases where the synchronisation process interacts non-obviously with an interference estimation/cancellation circuit.

Interference aspects are covered in many other classes:

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Inter Symbol Interference removed in Equalizers

H04L 25/03006

Interference in receivers

H04B 1/10

Further interference aspects at the receiver (EMI)

H04B 15/00

Interference due to the multiplexing of users (inter-users, inter-cell, adjacent channel)

H04J 11/0023

{with preamble design, i.e. with negotiation of the synchronisation sequence with transmitter or sequence linked to the algorithm used at the receiver}
Definition statement

This place covers:

The preamble sent by transmitter is constructed or negotiated in the light of the synchronisation process/algorithm used at the receiver.

{with channel estimation, e.g. determination of delay spread, derivative or peak tracking (channel estimation H04L 25/0202)}
Definition statement

This place covers:

As mentioned in the example above, the synchronisation process may interact with a particular channel estimation/tracking method.

References
Limiting references

This place does not cover:

Channel estimation per se

H04L 25/0202

Informative references

Attention is drawn to the following places, which may be of interest for search:

Measuring or estimating channel quality parameters

H04B 17/309

{in combination with other modulation techniques}
Definition statement

This place covers:

This subclass like H04L 27/2634 above covers interaction between the OFDM multiplexing and other circuit components.

{double density OFDM/OQAM system, e.g. OFDM/OQAM-IOTA system}
Definition statement

This place covers:

OFDM/OQAM generally has a real value modulated on each subcarrier and does not necessitate any Guard Interval to be inserted between contiguous symbols. It generally necessitates well localized (in time as well as in frequency domain) pulse shaping function.

Arrangements for maintenance, administration or management of data switching networks, e.g. of packet switching networks
Definition statement

This place covers:

Aspects relating to operation, administration, maintenance, and provisioning (OAMP) of heterogeneous data packet networks (e.g. IP, Ethernet, Next Generation Network ...) both using proprietary and standardised network management architectures and protocols (e.g. TMN, SNMP, OMA-DM) irrespective of the physical transport medium, the type of service carried and the type of virtualisation (e.g. cloud);

Although typical Network Management functions, aspects related to accounting/billing and security are in general not classified here. The only exceptions are Service quality based billing and security of the network management system (e.g. authorised access to the manager, security of management messages).

Relationships with other classification places

Aspects related to the management of the fulfilment of an agreement between two different parties (usually not within the same network/domain), typically known as Service Level Agreement (SLA), are classified under the H04L 41/50 subgroups.

aspects related to the monitoring of the performance of a network communications are classified under the H04L 43/00 subgroups (e.g. monitoring of QoS parameters).

Aspects related to the testing of a network or a network element are classified under H04L 43/50.

Aspects relating to specific functions of data storage and retrieval, e.g. in database, is covered under G06F 16/00

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Detection or prevention of error at physical layer

H04L 1/00

Accounting or billing for the transport of the data-packets

H04L 12/14

Operation and Maintenance of homogeneous ATM networks

H04L 2012/5625

Arrangement for network security

H04L 63/00

Controlling or operating of remote end-user devices' applications

H04L 67/125

Network management of traditional telephonic (circuit-switched) networks

H04M 3/22

Interconnection arrangements between voice switching centres. Network operation, administration, maintenance or provisioning

H04M 7/0081

Arrangements providing connection between exchanges

H04Q 3/0016

Selecting arrangements for multiplex systems using optical techniques

H04Q 11/0001

Wireless communication networks. Supervisory, monitoring or testing arrangements

H04W 24/00

Wireless communication networks. Network traffic or resource management

H04W 28/00

Special rules of classification

In these subgroups, unless otherwise indicated, classification is made according to the best place which embraces the invention. When several particular technical subjects are disclosed, this rule is separately applied to each of them.

Glossary of terms

In this place, the following terms or expressions are used with the meaning indicated:

Network Management, NM

refers to the activities, methods, procedures, and tools that pertain to the operation, administration, maintenance, and provisioning of networked systems.

Network Management functions

Functions that are performed as part of network management include Fault, Configuration, Accounting, Performance Security management (FCAPS).

Operation

deals with keeping the network up and running smoothly.

Administration

deals with keeping track of resources in the network and how they are assigned. It includes all the "housekeeping" that is necessary to keep the network under control.

Maintenance

is concerned with performing repairs and upgrades—for example, when equipment must be replaced, when a router needs a patch for an operating system image, when a new switch is added to a network. Maintenance also involves corrective and preventive measures to make the managed network run "better", such as adjusting device configuration parameters.

Provisioning

is concerned with configuring resources in the network to support a given service. For example, this might include setting up the network so that a new customer can receive the requested service.

Network Manager

An entity that acts in a manager role for performing the network management functions.

Agent

A software module that performs management functions requested by a Manager.

Network element (NE), managed device, managed node

Manageable logical entity uniting one or more physical devices which are networked. Network elements usually have management agents responsible for interfacing with the network manager. They can be any type of device, including, but not limited to: nodes, routers, switches, bridges, hubs, Network Interface Controller (NIC) hosts, gateways, servers, modem, IP telephones, IP video cameras, data-centres, computer hosts, and printers.

Managed object

an abstract representation of network resources of the network element that is managed.

Synonyms and Keywords

In patent documents, the following abbreviations are often used:

OA&M, OAM

Operation, administration and management

OAM&O, OAMP

Operation, administration, management and provisioning

OSS

Operations support systems

NM

Network Management

NMS

Network Management System

TMN

Telecommunications Management Network

SNMP

Simple Network Management Protocol

MIB

Management Information Base

TR-069

Technical Report 69 (Broadband forum standard)

ITU

International Telecommunication Union

IETF

Internet Engineering Task Force

OMA-DM

Open Mobile Alliance - Device Management

3GPP

3rd Generation Partnership Project

SOAP

Simple Object Access Protocol

In patent documents, the word/expression in the first column is often used instead of the word/expression in the second column, which is used in the classification scheme of this place:

Management

Controlling, commanding or operating

Configured to

Adapted to or suitable for defining functional features of structural elements

Standardisation; Integration
Definition statement

This place covers:

Use of standards NM protocols, standards architecture, arrangement and representation instrumental for a integrated management

Special rules of classification

This group covers a hierarchy of different miscellaneous aspects focusing on integration and standardisation. Classification is preferably made in the appropriate subdivision below.

Standardised network management protocols, e.g. simple network management protocol [SNMP]
Definition statement

This place covers:

Aspects related to modification or specific use of standards NM protocols. Additional examples are TR-069, OMA-DM.

Special rules of classification

If the type of standardized protocol is merely cited as general information the group is not to be allocated. Not conventional management protocol, like web-based, web service are classified under H04L 41/0246.

Multivendor or multi-standard integration
Definition statement

This place covers:

Managing network equipments from different vendors following different communication protocols and standards technologies;

Integration products capable of communicating with different managed nodes in their own protocol and capable of representing a unified network view to the network managers.

media0.png

Mapping or translating multiple network management protocols
Definition statement

This place covers:

Using different NM protocols, conversion of NM commands and reports from one NM protocol (e.g. CMIP) into another protocol (e.g. SNMP), mapping between different version of the same NM protocols (SNMP v2 and v3);

media1.png

Object-oriented techniques, for representation of network management data, e.g. common object request broker architecture [CORBA]
Definition statement

This place covers:

Using object oriented techniques (e.g. CORBA) for representation of NM data. Processing managed entities as Objects.

Special rules of classification

This class is to be allocated for OO-Techniques other than or beyond the typical use of objects in, e.g., SNMP (e.g. MIB's objects or OMA) which can be considered in the class H04L 41/0213 .

{using relational databases for representation of network management data, e.g. managing via structured query language [SQL]}
Definition statement

This place covers:

Use of networks being modelled by a (1:1) image in a relational database, e.g, management is done by issuing respective (SQL) commands.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Information retrieval in structured data stores

G06F 16/20

Exchanging or transporting network management information using the Internet; Embedding network management web servers in network elements; Web-services-based protocols
Relationships with other classification places

This group relates to aspects where the Internet or web applications and protocols are used for management, and it does not for conventional management protocol, like SNMP.

Aspects of Internet or web applications and protocols in general which are not instrumental to network management functions should be classified in H04L 67/00, in particular H04L 67/02.

The specific management functions should also be classified in the other appropriate H04L 41/00 subgroups, e.g. configuration in H04L 41/08, fault management in H04L 41/06.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Conversion of network management protocols

H04L 41/0226

Web-based network application protocols in general

H04L 67/02

Web-based network application protocols for remote control of end-devices or monitoring of remote application data

H04L 67/025

Proprietary application protocols for remote control of end-devices in special networking environments

H04L 67/125

Retrieval from the Internet

G06F 16/95

using browsers or web-pages for accessing management information
Definition statement

This place covers:

Aspects relating to accessing the management information by browsing web pages focusing on the communication capabilities.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Generic visualisation aspects of Graphical User Interface (GUI) for management

H04L 41/22

using e-messaging for transporting management information, e.g. email, instant messaging or chat
Definition statement

This place covers:

Aspects relating to embedding management objects or management commands or management data by using applications like email, chat.

using meta-data, objects or commands for formatting management information, e.g. using eXtensible markup language [XML]
Definition statement

This place covers:

Aspects relating to use of Internet language data, e.g. html, xml, for formatting management information, e.g. web services data.

using web services for network management, e.g. simple object access protocol [SOAP]
Definition statement

This place covers:

Aspects relating to use of SOAP, or other protocols for enveloping/encapsulation of management data.

{for synchronisation between service call and response}
Definition statement

This place covers:

Aspects relating to timing between the client and server communication (request, response) for monitoring or exchanging management data.

aspects related to push or pull or polling or event-based transmission of management data.

{for search or classification or discovery of web services providing management functionalities}
Definition statement

This place covers:

Finding a list of available services, e.g. by using UDDI;

aspects related to how the service is to be accessed, e.g. by using WSDL

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Network applications and protocols for service discovery

H04L 67/51

{for accessing web services by means of a binding identification of the management service or element}
Definition statement

This place covers:

Aspects relating to address resolver (e.g. URL) or path identification for accessing web resources.

Aspects related to physical or logical identification of management client/server.

Relationships with other classification places

Aspects of naming and addressing in general is covered by H04L 61/00

Network management architectures or arrangements
Definition statement

This place covers:

Aspects on how the NMS is structurally organised;

Aspects on how the NMS is connected for retrieving the management information.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Architecture of monitoring probes

H04L 43/12

comprising distributed management centres cooperatively managing the network
Definition statement

This place covers:

Multiple NM centers or NM units communicating with each other and managing the network together and all managers being on the same hierarchical level - peer to peer relation.

Synchronisation and coordination among different managers.

Examples: EP1624615, EP2053780

Special rules of classification

The different multivendor network managers under the group H04L 41/022 do not necessarily cooperate with each other but they operate independently.

comprising hierarchical management structures
Definition statement

This place covers:

Hierarchical structures like main manager > medium (mid - level -) managers > sub-managers.

media2.png

comprising client-server management architectures
Definition statement

This place covers:

Aspects related to the specific type of NM architecture comprising client and server type of relationship, i.e. one central server and one or multiple clients connected to the server, wherein the management network provides the client-server architecture (architecture of the managed network is irrelevant).

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Standardised network management protocols, e.g. simple network management protocol [SNMP]

H04L 41/0213

Protocols for client-server architectures

H04L 67/01

comprising network management agents or mobile agents therefor
Definition statement

This place covers:

Usage of NM agents. Management agents are usually implemented in the managed network nodes themselves or reside "close" to the managed nodes in the network. They usually support the standard NM protocols or provide a mapping functionality between the nodes' proprietary and the managers standardized protocol (e.g. proxy).

media3.png

Special rules of classification

This symbol is to be allocated for use and features of Agents other than or beyond the typical use already done in, e.g., SNMP standardised protocols, which can be considered in the group H04L 41/0213.

{mobile agents}
Definition statement

This place covers:

Agent which are able to move from one place to another, e.g. from a NMS to a managed element.

using standardised network management architectures, e.g. telecommunication management network [TMN] or unified network management architecture [UNMA]
Definition statement

This place covers:

Aspects related to the specific type of standard NM architecture used.

Management of faults, events, alarms or notifications
Definition statement

This place covers:

Aspects related to the generation, processing of notifications, error messages, managements messages originated from the network instrumental to determine the network behaviour.

Relationships with other classification places

Aspects related to active monitoring of the status or availability of the network elements which are triggered by a NMS or a monitoring system are classified under the H04L 43/00 subgroups.

Fault tolerance in computer systems is classified under G06F 11/00. In general, if restoration of faults is performed without a NMS but rather with the involvement of the end nodes (CPUs in multiprocessor systems, Personal Computers in computer networks, or Operating System or applications running on the end nodes) then classification should be done in the G06F 11/00 groups, as indicated below:

Responding to the occurrence of a fault, e.g. fault tolerance

G06F 11/07

Error or fault processing without redundancy, i.e. by taking additional measures to deal with the error/fault

G06F 11/0703

Error detection or correction of the data by redundancy in operation

G06F 11/14

Error detection or correction of the data by redundancy in hardware

G06F 11/16

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Alarm or failure messages notified by the user, customer (trouble ticket); Alarm or messages triggered by the user, handling of user's trouble tickets

H04L 41/5074

Active monitoring the status or the connection of network elements

H04L 43/10, H04L 43/0811, H04L 43/0817

Tracking events generated by the networked application user's

H04L 67/535

Fault management in exchanges' connections

H04Q 3/0075

Glossary of terms

In this place, the following terms or expressions are used with the meaning indicated:

Error

A deviation of a system from normal operation.

Fault or failure

Lasting error or warning condition.

Event

Something that happens which may be of interest. A fault, a change in status, crossing a threshold, or an external input to the system, for example.

Notification

Unsolicited transmission of management information from network managed entity to network manager.

Trap

Asynchronous notification from managed device (or agent thereof) to NMS

Alarm or alert

Indication of the occurrence of a fault.

faulty entity

a network element or a sub-part thereof in charge of communication functionalities, e.g. NIC.

using filtering, e.g. reduction of information by using priority, element types, position or time
Definition statement

This place covers:

Reduction of the notifications' number. Often the network manager is overwhelmed with floods of alarms in complex networks. Filters can be set to only show these events the network managers considers "relevant" at a given time representing a subset.

Aspects related to classification, suppression, grouping of notifications

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Filtering or reduction of monitored data packets

H04L 43/02

Error or fault reporting or logging, in computer systems

G06F 11/0766

{based on severity or priority}
Definition statement

This place covers:

Aspects relating to discriminate among messages which are less or more relevant or urgent.

{based on the type or category of the network elements}
Definition statement

This place covers:

Aspects relating to discriminate among messages which are originated by different kind of devices (e.g. routers instead of switches).

{based on the physical or logical position}
Definition statement

This place covers:

Filtering/reducing based on topological/geographical information of the network elements.

{based on time}
Definition statement

This place covers:

Filtering/reducing depending on the time the messages were generated.

{by acting on the notification or alarm source}
Definition statement

This place covers:

Aspects related to interventions on the notifications source for stopping or limiting the sending of messages.

using root cause analysis; using analysis of correlation between notifications, alarms or events based on decision criteria, e.g. hierarchy, tree or time analysis
Definition statement

This place covers:

Correlating notifications or messages for identifying the relevant information pointing to the same problem.

Determination of the root of a problem in general;

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Identification of network element affecting the current service quality

H04L 43/091

Error or fault localisation, by collation, in computer systems

G06F 11/0703

{by additionally acting on or stimulating the network after receiving notifications}
Definition statement

This place covers:

Use of additional signalling for locating the root of a problem.

using network fault recovery (ring fault isolation or reconfiguration in loop networks without recovery actions by a network management system H04L 12/437)
Definition statement

This place covers:

Recovery from network faults with the involvement of a NMS.

Aspects relating to the management signalling for re-establishing the communication functionalities of elements.

Automatically "repairing" broken links, nodes, routes by a NMS when the network is up.

Relationships with other classification places

Redundancy within network elements, for example routers with redundant CPUs or interconnections, is classified under G06F 11/00. Where the G06F 11/00 groups refer to "interconnections", they are meant to be physical media and are of point-to-point type or of bus type.

References
Limiting references

This place does not cover:

Ring fault isolation or reconfiguration

H04L 12/437

Informative references

Attention is drawn to the following places, which may be of interest for search:

Selection of a alternate/backup route

H04L 45/22

Route fault recovery

H04L 45/28

Techniques for recovering from a failure of a protocol instance or entity

H04L 69/40

Error or fault handling in computer systems

G06F 11/0793

by isolating or reconfiguring faulty entities
Definition statement

This place covers:

Removing or switching off a faulty entity without replacement.

Command or instructions for dynamically by-passing the faulty entity toward other paths, possibly by informing the neighbouring nodes.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Reconfiguration of paths in computing systems

G06F 11/1423

Active fault-masking in computer systems, where interconnections are redundant

G06F 11/2002

Performing the actions predefined by failover planning, e.g. switching to standby network elements
Definition statement

This place covers:

Offline failover planning, command and instructions from the NMS to re-direct to a different path previously calculated.

by dynamic selection of recovery network elements, e.g. replacement by the most appropriate element after failure
Definition statement

This place covers:

Replacement by the best or redundant element in terms of similar capabilities/functionalities, not just replacement of the path.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Active fault-masking in computer systems, where processors are redundant

G06F 11/202

{by re-configuring the faulty entity}
Definition statement

This place covers:

Re-booting/starting (possibly after a waiting time), re-initialise, re-setting or re-configuring (by changing parameters) in order to repair the faulty entity into the network.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Re-configuration in response to network events

H04L 41/0816

Bootstrapping procedure in computers

G06F 9/4401

Error or fault handling in computer systems

G06F 11/0793

Faults occurring during boot-up procedure in computer systems

G06F 11/1417

Localisation of faults
Definition statement

This place covers:

Determining or detection of a fault with particularly emphasis on the physical or logical position of the problem with or without event correlation.

Relationships with other classification places

Aspects related to the active monitoring of the status of network elements is under H04L 43/00, specifically H04L 43/0817. However, if the monitoring activity gives rise to a the determination of a failure's position then the group H04L 41/0677 is also to be allocated.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Error or fault detection or monitoring in computer systems

G06F 11/0751

Configuration of triggering conditions
Definition statement

This place covers:

Aspects relating to the setting of events, fault, alarm or trap conditions or threshold, metrics, which give arise to a error message,definition of a fault.

Aspects relating to when an alert is to be generated.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Threshold monitoring

H04L 43/16

Additional information in the notification, e.g. enhancement of specific meta-data
Definition statement

This place covers:

Notification data-model.

Added-value aspects of the content of the notifications, like position, time, failure type, etc..

Adding information to the notifications, description of the notifications' attributes.

using logs of notifications; Post-processing of notifications
Definition statement

This place covers:

Using of libraries, database or data structure parameters for saving alarms, notifications or events.

Off-line extraction or post-processing for statistics purposes or graphical representation

Examples: WO2013023837

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Error or fault reporting or logging in computer systems

G06F 11/0766

the faulty arrangement being the maintenance, administration or management system
Definition statement

This place covers:

Actions when the manager itself fails;

Configuration management of networks or network elements (address allocation H04L 61/50)
Definition statement

This place covers:

Aspects relating to dynamic or off-line functionality to perform operations that will provide physical and logical parameters settings to/from network or network elements.

Determination and storing of configuration information.

References
Limiting references

This place does not cover:

Address allocation

H04L 61/50

Informative references

Attention is drawn to the following places, which may be of interest for search:

Proprietary application protocols for remote control of end-devices in special networking environments

H04L 67/125

Configuration management in the context of software development

G06F 8/71

Configuration of software in general

G06F 9/44505

Automatic configuration in wireless networks

H04W 24/02

Configuration setting
Definition statement

This place covers:

Aspects relating to assign configurations;

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Provisioning or reconfiguring application services over wireless networks

H04W 4/00

automatic configuration in wireless networks

H04W 24/02

for initial configuration or provisioning, e.g. plug-and-play
References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Configuration of networked applications configuration parameters

H04L 67/34

Configuration management in the context of software development

G06F 8/71

Configuration of software in general

G06F 9/44505

{Plug-and-play configuration}
Definition statement

This place covers:

Aspects relating to configuration as soon as an element is being connected.

The network element having already configuration parameters ready.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Software configuration of peripheral devices

G06F 9/4411

electrical coupling for live connection to bus

G06F 13/4081

the condition being updates or upgrades of network functionality
References
Informative references

Attention is drawn to the following places, which may be of interest for search:

topology update or discovery for routing purposes

H04L 45/02

characterised by the purposes of a change of settings, e.g. optimising configuration for enhancing reliability (for optimising operational conditions of wireless networks H04W 24/02)
Definition statement

This place covers:

Aspects focusing on the aim of the configuration settings, for improving certain conditions, e.g. reliability or reducing downtime.

References
Limiting references

This place does not cover:

Optimising operational conditions of wireless networks

H04W 24/02

for reduction of network costs (H04L 41/0833 takes precedence)
Definition statement

This place covers:

Configuration aiming at reducing the number or use or maintenance of network components, devices, links, functionalities or the cost associated to a function of the network or the path.

References
Limiting references

This place does not cover:

For reduction of network energy consumption

H04L 41/0833

Retrieval of network configuration; Tracking network configuration history
Definition statement

This place covers:

Aspects relating to reading or auditing configuration information of network elements;

Special rules of classification

This group covers a hierarchy of different miscellaneous aspects focusing on retrieving configuration data. Classification is preferably made in the appropriate subdivision below.

{by backing up or archiving configuration information}
References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Details of backing up or restoring data

G06F 11/1446

{by rolling back to previous configuration versions}
References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Details of restoration of backup data

G06F 11/1415

Checking the configuration
Definition statement

This place covers:

Aspects relating to validation, comparison of configuration's data.

{Aspects of the degree of configuration automation}
Special rules of classification

This group covers a hierarchy of different miscellaneous aspects focusing on how automatic the configuration is carried out. Classification is preferably made in the appropriate subdivision below.

These groups are usually to be allocated in combination with the other groups of H04L 41/08.

Assignment of logical groups to network elements
Definition statement

This place covers:

Aspects related to the logical clustering of network elements, e.g. grouping according to configuration parameters or network element functionality.

Policy-based network configuration management
Definition statement

This place covers:

Aspects related to the definition and/or use of policies and/or rules for the processing of network element configuration data.

Aspects related to network management functionalities within Policy and Charging Control, e.g. 3GPP policy architecture (PCRF, PCEF, SPR).

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Policy and charging Control architecture for metering, charging or billing

H04L 12/1407

Network security policies

H04L 63/20

Configuration of virtualised networks or elements, e.g. virtualised network function or OpenFlow elements
Definition statement

This place covers:

Aspects covering specifically operations defined for configuration management when the network or network elements are virtualised.

Special rules of classification

As far as configuration of the virtualised networks or network elements involves relevant aspects covered by subgroups H04L 41/0803 - H04L 41/0894, these aspects are additionally classified under the relevant subgroups, e.g. operations defined for the activation or instantiation of virtualised entities such as VNFs or Service Chains of VNFs are classified with H04L 41/0895 and H04L 41/0806.

Bandwidth or capacity management, i.e. automatically increasing or decreasing capacities (flow or congestion control using dynamic resource allocation, e.g. in-call renegotiation, H04L 47/76)
Definition statement

This place covers:

Involvement of a manager for configuring elements in order to cope with the bandwidth request.

References
Limiting references

This place does not cover:

Flow or congestion control using dynamic resource allocation, e.g. in-call renegotiation

H04L 47/76

by horizontal or vertical scaling of resources, or by migrating entities, e.g. virtual resources or entities
Definition statement

This place covers:

Aspects dealing with the scaling by instantiating additional or removing virtualised entities or by adapting the capacity of the virtualised entities, e.g. runtime optimisation of network slices or VNFs or VMs.

Aspects dealing with the migration of virtualised entities in a virtualised environment in order to ensure the consistent transfer of information and connections.

Aspects of the orchestrator, cloud manager, SDN controller or virtual network manager entities performing these scaling and migration operations.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Hypervisor specific management aspects

G06F 9/45558

Virtual machine migration in general

G06F 9/4856

Discovery or management of network topologies
Definition statement

This place covers:

  • Determination, retrieval or use of network topology (also based on routing table information) for network management purposes (e.g. Fault localisation, network analysis, configuration, graphical representation, mapping...) Both a link or network layer.
  • Discovery of links, network elements and adjacencies within a network;
  • Aspects relating to topology change after migration;
  • Planning of the appropriate topology.
References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Monitor simple connectivity of an element

H04L 43/0811

Topology update for routing purposes

H04L 45/02

Details of backing up or restoring data

G06F 11/1446

Topology discovery in wireless networks for routing purposes

H04W 40/24

of virtualised topologies, e.g. software-defined networks [SDN] or network function virtualisation [NFV]
Definition statement

This place covers:

Arrangements and functions wherein the appropriate topology for the virtualised network is determined and established, e.g. based on requirements such as the ones derived from "multi-tenant sites", "multi-sites" and customers' requirements.

Aspects related to the mapping of virtual or logical elements to physical elements, the virtualised network topology comprising hierarchies or layers of network elements and aspects of the distribution of controllers and forwarding entities in the network.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Arrangements for network security, VPNs

H04L 9/40, H04L 63/0272

Local partitioning of resources

G06F 9/5077

Network analysis or design
Definition statement

This place covers:

Aspects related to the analysis or the plan of a network.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Network monitoring

H04L 43/00

Special rules of classification

This group covers miscellaneous aspects focusing on the analysis of the network.

Classification is preferably made in the appropriate subdivision below.

The sub-groups do not simple relate to monitoring of packets H04L 43/00 but more advanced analysis, analysis of management messages, aggregation of information in different part of the network, analysis of the network as a whole.

If the analysis is only "punctual" (single link, single path, specific elements) monitoring H04L 43/00 is to be considered.

using statistical or mathematical methods
Definition statement

This place covers:

Evaluation of monitored data applying advanced statistical methods and tests going beyond basic counting and averaging of frames, errors. Detecting anomalies, The analysis can be based on input from real data, when the network is or was operative.

Aspects of traffic modelling, e.g. Poisson, Markov, self-similar.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Generation of artificial traffic for testing

H04L 43/50

{involving simulating, designing, planning or modelling of a network}
Definition statement

This place covers:

Network design tools (e.g. with integrated simulation and design testing).

Modelling or abstraction of the network for behaviour simulation.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Modelling of isolated elements of the network, auditing

H04L 41/0233, H04L 41/085

Network topology's graph or modelling

H04L 41/12

Network design in exchanges connections

H04Q 3/0079

Radio cell planning

H04W 16/00

for predicting network behaviour
Definition statement

This place covers:

The outcome of the network's analysis are instrumental for determining the future behaviour of the network, e.g. bandwidth forecast.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Modelling of isolated elements of the network, auditing

H04L 41/0233, H04L 41/085

Fault management

H04L 41/06

Radio cell planning

H04W 16/00

for prediction of maintenance
Definition statement

This place covers:

Aspects related to the prediction of the maintenance needs due to the future forecast behaviour of network or network elements.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Fault management

H04L 41/06

using machine learning or artificial intelligence
Definition statement

This place covers:

Applying artificial intelligence methods (expert systems, rule based systems, genetic algorithms) in NM.

Delegation of network management function, e.g. customer network management [CNM]
Definition statement

This place covers:

Giving the customer (limited) access to NM functions.

{Network management software packages}
Definition statement

This place covers:

Particular aspects (e.g., customization, programmability or configuration) of NM software tools like HP Openview, Netview 6000, with GUIs (Graphical User Interfaces) capable of managing large and complex data networks.

comprising specially adapted graphical user interfaces [GUI]
Definition statement

This place covers:

Using a GUI to represent the architecture of the network.

Which/how the management information are displayed.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Using a browser for accessing management information

H04L 41/0253

Graphical visualization of monitored data

H04L 43/045

Special rules of classification

In group H04L 41/22, the focus is on the graphical representation of the managed network, elements, objects, whereby H04L 41/0253 relates to the access to web-based management content via a browser. Graphical/visualization aspects of web browsers are therefore classified under H04L 41/22.

{using dedicated network management hardware}
Definition statement

This place covers:

(Portable) hardware equipment for managing (e.g. configuring, logging management data, etc.) a device at a time.

Craft terminals used by fields technicians.

Built-in NM hardware.

{using dedicated tools for LAN [Local Area Network] management}
Definition statement

This place covers:

Usually NM tools operating at MAC level.

Examples: US2010281106, US2009113046

Restricting access to network management systems or functions, e.g. using authorisation function to access network configuration
Definition statement

This place covers:

Only security related to the NM system.

Aspects relating to keeping the manager and the management data secure.

Restricting access control to the NMS, encryption of management data.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Cryptography for secret or secure communication

H04L 9/00

Protocols or architecture for network security

H04L 63/00

Protecting computers or computer systems against unauthorised activity

G06F 21/00

Wireless network security

H04W 12/00

{Decision processes by autonomous network management units using voting and bidding}
Definition statement

This place covers:

Process for electing a unit as a master.

Bidding and electing units based on best QoS level.

{Specific management aspects for broadband networks}
Definition statement

This place covers:

NM for traditional broadband digital cross-connect switches supporting user's communication, now being replaced by ATM or DSL-based infrastructure.

Signalling channels for network management communication
Definition statement

This place covers:

Aspects of how network administration and management data are transferred, e.g. details of the transport procedure or details of transfer schemes for in-band transport of management data over the same physical and logical infrastructure as the user plane data traffic.

Data signalling between network management entities.

Aspects related to the use of network management tunnels between network devices, e.g. protocols for enveloping/encapsulation of management data.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Conversion of network management protocols

H04L 41/0226

Exchanging or transporting network management information using Internet; Embedding network management web servers in network elements; Web-services-based protocols

H04L 41/0246

Web-based network application protocols in general

H04L 67/02

Web-based network application protocols for remote control of end-devices or monitoring of remote application data

H04L 67/025

Proprietary application protocols for remote control of end-devices in special networking environments

H04L 67/125

between virtual entities, e.g. orchestrators, SDN or NFV entities
Definition statement

This place covers:

Actions and arrangements involving the communication between virtual network management entities, e.g. NFV-MANO orchestrator, cloud managers, VNFM, VIM, VMs, VNFs.

Actions and arrangements involving communication between a plurality of SDN controllers or communication between a network management entity and orchestrator(s)/controller(s). The communication including signalling between SDN controllers for indicating forwarding information on reachability at one or more layers for network management purposes.

Actions and arrangements involving the communication between an SDN controller and one or a plurality of forwarding entity/entities for network management.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Management of faults, events, alarms or notifications

H04L 41/06

Configuration management

H04L 41/08

Policy based network configuration management

H04L 41/0894

Ensuring SLA

H04L 41/5019

Monitoring or testing data switching networks

H04L 43/00

Updating the topology between route computation elements

H04L 45/036

Using an overlay routing layer

H04L 45/64

Out-of-band transfers
Definition statement

This place covers:

Definition or use of an out-of-band management signalling layer.

Aspects concerning management data transfer via outband or out-of-band (OOB) channel, e.g. wherein OOB signalling is channeled via dedicated NEs which are independent and physically distinct from those in the data network.

Aspects wherein NMS manages NEs even if an inband service channel fails by using a secondary transmission channel dedicated for the transport of network management information.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Using different networks or paths for security, e.g. using out of band channels

H04L 63/18

using virtualisation of network functions or resources, e.g. SDN or NFV entities
Definition statement

This place covers:

Aspects covering specific management or orchestration operations to explicitly specify them as being associated to network function virtualisation or resources virtualisation, e.g. virtualisation aspects in fault management.

Aspects covering logical centralisation of network intelligence and state, e.g. virtualisation of network resources as most relevant features such as those defined in Software Defined Network and ETSI NFV Network Function Virtualisation, e.g. NFV Management and Orchestration (NFV-MANO) or 3GPP Network Slice Subnet Management Function (NSSMF) as shown in the figure below.

media28.png

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Arrangements for monitoring or testing data switching networks

H04L 43/00

Routing or path finding of packets in data switching networks

H04L 45/00

Traffic control in data switching networks

H04L 47/00

Packet switching elements

H04L 49/00

Network arrangements or protocols for supporting network services or applications

H04L 67/00

Optical switching

H04Q 11/0001

Special rules of classification

As far as network management using virtualisation of networks or network elements involves relevant aspects covered by H04L 41/00 subgroups which are not exclusively defined for virtualised entities, these aspects are additionally classified under the relevant subgroups. For instance, root cause analysis in a virtualised network is classified in groups H04L 41/0631 and H04L 41/40

Network service management, e.g. ensuring proper service fulfilment according to agreements
Definition statement

This place covers:

aspects relating to Service level management between parties for service deployment, assurance and review over heterogeneous packet-switched data networks (e.g. IP, Ethernet, ...) irrespective of the physical transport medium and the type of service carried and the type of virtualisation (e.g. cloud).

Glossary of terms

In this place, the following terms or expressions are used with the meaning indicated:

Service Level Management

provides for continual identification, monitoring and review of the levels of IT services specified in the Service Level Agreements (SLAs). Service Level Management ensures that arrangements are in place with internal IT Support-Providers and external suppliers in the form of Operational Level Agreements (OLAs) and Underpinning Contracts (UCs), respectively.

Service Level Management functions

ensuring that the agreed IT services are delivered when and where they are supposed to be; liaising with Availability Management, Capacity Management, Incident Management and Problem Management to ensure that the required levels and quality of service are achieved within the resources agreed producing and maintaining a Service Catalogue (a list of standard IT service options and agreements made available to customers) ensuring that appropriate IT Service Continuity plans exist to support the business and its continuity requirements.

Service Level Agreement, SLA

service level agreement is a part of a service contract where the level of service is formally defined.

Quality of Service, QoS

quality measure relating to specific network parameters of traffic packets (bit rate, delays, packet loss...) which describe the treatment experienced by the packets while passing through the network .

SLA vs QoS

In order to meet the SLA requirements specific internal QoS management processes are to be implemented. SLA is namely directed to an 'aggregation' of (end-to-end) QoS parameters rather than to specific internal network metrics or is directed to QoS related to a customer (QoE).

Quality of Experience, QoE

a subjective measure of a customer's experiences with a service.

Synonyms and Keywords

In patent documents, the following words/expressions are often used with the meaning indicated:

"QoS"

of "Service Level performance" (e.g. AU2008201028, paragraph 8)

Managing SLA; Interaction between SLA and QoS
Definition statement

This place covers:

General aspects relating to the description of the terms or properties of the SLA.

Aspects relating to mapping/converting SLA requirements into QoS parameters.

Illustrative example of subject matter (ITU-T Rec. E.860) classified in this group.

media4.png

Creating or negotiating SLA contracts, guarantees or penalties
References
Informative references

Attention is drawn to the following places, which may be of interest for search:

SLA negotiation in wireless networks

H04W 28/24

Determining service level performance parameters or violations of service level contracts, e.g. violations of agreed response time or mean time between failures [MTBF]
Definition statement

This place covers:

Aspects relating to the benchmarking for specific services.

Aspects relating to mean time to failure (mttf), mean time to recover (mttr).

Aspects relating to the overall performance of a network, e.g. Delay, reliability based on aggregation of qos parameters.

Measuring specific key performance indicators (kpi).

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Monitoring performance metrics on a simple network level

H04L 43/08

Ensuring fulfilment of SLA
References
Informative references

Attention is drawn to the following places, which may be of interest for search:

flow or congestion control at network level

H04L 47/10

by proactively reacting to service quality change, e.g. by reconfiguration after service quality degradation or upgrade
References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Network faults recovery

H04L 41/0654

Changing configuration due to adaption

H04L 41/0813

{Service quality level-based billing, e.g. dependent on measured service level customer is charged more or less}
References
Informative references

Attention is drawn to the following places, which may be of interest for search:

General charging or billing for transport of data packets

H04L 12/14

{Generating service level reports}
Definition statement

This place covers:

Generating a report based on data showing the performance levels for individual customers or individual services

Automatic deployment of services triggered by the service manager, e.g. service implementation by automatic configuration of network components
References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Initializing Configuration, i.e. provisioning of network or devices

H04L 41/0806

{Service discovery by the service manager}
Definition statement

This place covers:

Identifying service elements or services and dependencies among the elements and services of a network

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Determining the actual topology of a network

H04L 41/12

Topology discovery in routers

H04L 45/02

Arrangements for service discovery, e.g. Service Location Protocol (SLP)

H04L 67/51

characterised by the interaction between service providers and their network customers, e.g. customer relationship management
Definition statement

This place covers:

Order and problem handling, informing end-user of service situation.

{Customer relationship management}
Definition statement

This place covers:

  • Handling of customer data, contracts, customer history
  • Monitoring and recording customer interactions with the provider
  • Data mining techniques for customer's data processing
References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Arrangements involving Customer Network Management, i.e. giving the customer access to network management functions

H04L 41/18

Customer-centric QoS measurements
Definition statement

This place covers:

Aspects relating to the quality or satisfaction as perceived by the customer/user, Quality of Experience (QoE).

Aspects relating to reports provided by the customer about the service quality.

Filtering out customers affected by service problems
Definition statement

This place covers:

Identifying customers affected by service problems as network element failures, network congestion or service degradation.

Handling of user complaints or trouble tickets
Definition statement

This place covers:

Aspects relating to the generation of error messages, notifications, issues, incident originated by a customer or a customer's terminal to be treated by the Service Provider.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Alarm messages (automatically) triggered by faulty network elements

H04L 41/0677

{wherein the managed service relates to simple transport services, i.e. providing only network infrastructure}
Definition statement

This place covers:

Aspects wherein access or connectivity to the network itself is the service, e.g. offering VLAN.

{based on type of value added network service under agreement}
Special rules of classification

The H04L 41/508 groups should be allocated only in combination with at least one of the groups from H04L 41/50 - H04L 41/5074 and only if essential for the characterisation of the service management aspects.

{wherein the managed service relates to web hosting}
References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Web-based network application protocols

H04L 67/02

Web site content organisation and management

G06F 16/958

Video-hosting

H04N 21/2743

{wherein the managed service relates to voice services (management of VoIP services H04M 7/0081)} 
References
Limiting references

This place does not cover:

Management of VoIP services

H04M 7/0081

Informative references

Attention is drawn to the following places, which may be of interest for search:

Protocols for real-time multimedia communications

H04L 65/00

Management of telephonic communication services

H04M 3/22

{wherein the managed service relates to media content delivery, e.g. audio, video or TV}
References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Protocols for real-time multimedia communications

H04L 65/00

Interactive television or video on demand [VOD]

H04N 21/00

{wherein the managed service relates to messaging or chat services}
References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Conducting a computer conference

H04L 12/1822

Messaging, e.g. e-mail or instant messaging in packet-switching networks

H04L 51/00

{wherein the managed service relates to distributed or central networked applications}
References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Management of file systems

G06F 16/10

Management of structured data stores

G06F 16/20

Arrangements for monitoring or testing data switching networks
Definition statement

This place covers:

  • Aspects of 'passive' monitoring, e.g. Observing the network by measuring passing traffic or setting counters here and there at different points in the network
  • Aspects of 'active monitoring', by introducing specific packets or modifying real data packets (also called testing)
  • Monitoring qos parameters of traffic;
  • Monitoring of metrics of network elements;
  • Measuring performance at network/link level (availability, status)
  • Report of monitored parameters;
  • Testing environment and routine;
  • Test traffic characterization
Relationships with other classification places

Traffic and packet monitoring techniques in H04L 43/00 are irrespective of the use which is done of the result and focuses on the monitoring techniques as such, not on the application which may be of different nature.

The group H04L 43/50 focuses on the testing platform, routine, apparatus and configuration.

Aspects related to the generation or insertion of specific type of packets (e.g. ICMP, ping, traceroute) are classified under H04L 43/10 whereas (test) traffic injection of data according to a pattern and characterization is under H04L 43/50.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Filtering policies for separating internal from external traffic for security

H04L 63/0227

Monitoring for detecting or protecting against malicious traffic

H04L 63/1408

Tracking the activity of the application user

H04L 67/535

Monitoring of computer activity

G06F 11/34

Synonyms and Keywords

In patent documents, the following words/expressions are often used with the meaning indicated:

"testing"

"monitoring" or "active monitoring".

Capturing of monitoring data
Definition statement

This place covers:

Aspects relating to the selection of specific type/group of packets

by sampling
Definition statement

This place covers:

Aspects relating to the storing of selection of packets being which is a representative subset of packets.

by adaptive sampling
Definition statement

This place covers:

Dynamically adjusting the sampling rate according to specific criteria, e.g. traffic burstiness, packet rate, statistics.

using flow identification
Definition statement

This place covers:

Aggregating captured packet data into flows, a flow being defined as a unidirectional sequence of packets all sharing same network parameters mainly based on header information.

Monitoring flow, wherein the flow is usually characterised by a n-tuple of network parameters, e.g. Source/destination address, port number, protocol number (e.g. Ietf ipfix, netflow)

Monitoring, identify or classify the flow on different osi-layers.

by filtering
Definition statement

This place covers:

Reduction of monitored data by applying filters to extract specific type of packets or part of packets;

Deep packet inspection (e.g. Bpf, libpcap) including payload analysis.

Using hashing, masking for extracting and storing packets or part of packets.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Alarm or event filtering

H04L 41/0604

Filtering policy for separating internal from external traffic for security

H04L 63/0227

Processing captured monitoring data, e.g. for logfile generation
Definition statement

This place covers:

Aspects focusing on aggregation and post-processing (including exporting, transmitting) of the monitored data, post-correlation.

Storing or logging of (part of) monitored packets.

Creation of specific data structure of the monitored packets.

for graphical visualisation of monitoring data
Definition statement

This place covers:

Displaying, showing of the monitoring data/result in graphs, x-y axis, drawings.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Use of a GUI as a tool for monitoring or managing a network

H04L 41/22

Display of network or application conditions affecting the applications

H04L 67/75

Visual indication of the functioning of a computing machine

G06F 11/32

Generation of reports
Definition statement

This place covers:

Aspects focusing on accumulation of data extracted from packet flows for reporting or for simple statistics purposes.

related to network traffic
Definition statement

This place covers:

Reporting the overall traffic on a Tap-Point in the network.

related to network devices
Definition statement

This place covers:

Reporting traffic characteristics for a specific device or network node.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Reporting of sensed information of home appliances managing a network

H04L 12/2803

using time frame reporting
Definition statement

This place covers:

Formatting traffic reports with respect to certain time intervals, e.g. per second, minute, hour, day or week, or configurable timeframes

Monitoring or testing based on specific metrics, e.g. QoS, energy consumption or environmental parameters
Definition statement

This place covers:

Aspect of monitoring of packets on a network (link/node) level including QoS parameters;

Aspect of monitoring of network elements' parameters (temperature, power consumption, etc.) via network protocols.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Measuring performance on a service level

H04L 41/5009

by checking connectivity
Definition statement

This place covers:

Monitoring whether a link is active or a device is connected

Checking or verifying both physical and logical connectivity, e.g., by using connectivity/continuity check messages;

Use of techniques at layer 2 or 3 of the OSI-stack.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Topology's determination

H04L 41/12

by checking functioning
Definition statement

This place covers:

Monitoring the status of the connected device for whether the device is working properly, monitoring network element resource metrics like memory utilization or printer utilization.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Monitoring appliance functionality of home appliances

H04L 12/2803

Monitoring the activity of the application user

H04L 67/535

Errors, e.g. transmission errors
References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Management of events, faults or alarms

H04L 41/06

Packet loss
Definition statement

This place covers:

Monitoring of transmission data loss for all upper layers (Layers 2, 3 and above), as e.g. packet/frame/PDU loss, is classified in groups H04L 43/0829/low. A loss is often recognized via expiration of a timer (timeout) and can be caused by full buffer, overloading, discarding.

{Transmission error}
Definition statement

This place covers:

Monitoring of transmission errors include all layer independent errors which can be recognized after reception of any transmitted data as bit errors (as e.g. CRC/checksum errors), packet errors (as e.g. duplicate packet errors, packets received after close errors), framing errors (frames too long/short), alignment errors, framing checksum (FCS) errors, bad header errors, carrier sense errors, packet collisions, late collision errors, excessive collision errors, backward errors, duplicate message acknowledgements (ACKs), out of order packet errors.

Delays
Definition statement

This place covers:

Different type of packet delays (transition time), also due to node or stack processing, buffering.

Special rules of classification

This class and the groups refer to delays irrespective of the use that is done of the delay information. For example the use of delay information for synchronizing time/clock is to be classified in H04J 3/0635.

Network utilisation, e.g. volume of load or congestion level
Definition statement

This place covers:

Aspects relating to the number of packets.

Utilisation of link capacity
Definition statement

This place covers:

Level of congestion, i.e. percentage or absolute value of link capacity available or used.

Throughput
Definition statement

This place covers:

Observing the time required to get a certain amount of bits across a link or path, thus the ratio of bits per time unit.

Packet rate
Definition statement

This place covers:

Monitoring bandwidth or packet data rate used by a traffic stream.

Measuring contribution of individual network components to actual service level
Definition statement

This place covers:

Aspects related to identification of network entities such as nodes, links, applications, that contribute to or are responsible for actual Service Level performance, such as service failure or service quality degradation, wherein the network entities provide the service for which a Service Level Agreement exists.

Aspects related to measuring the contribution of network entities to the actual Service Level.

Relationships with other classification places

Aspects of Service Level Management between parties for Service Level Agreement definition, Service Level assurance or Service deployment are covered by H04L 41/50 and its subgroups.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Management of faults, events, alarms or notifications using root cause analysis; Using analysis of correlation between notifications, alarms or events based on decision criteria, e.g. hierarchy, tree or time analysis

H04L 41/0631

Network service management, e.g. ensuring proper service fulfilment according to agreements

H04L 41/50

Active monitoring, e.g. heartbeat, ping or trace-route
Definition statement

This place covers:

Aspects related to the use of specific (standardised / well-known) 'smart' packets (ICMP, ping, probe packets, etc.) in the monitored network which stimulates a certain reaction from the monitored network.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Injection or characterization of test traffic

H04L 43/50

using time related information in packets, e.g. by adding timestamps
Definition statement

This place covers:

Inserting time-related information to the exchanged packets.

Network monitoring probes
Definition statement

This place covers:

Aspects specifically related to passive devices, e.g. meters, capturing data units (packets, cells, frames) transiting the monitored communications network;

Distribution, architecture, topology of the monitoring devices like sniffers, taps;

Internal architecture of a probe (buffer, processor).

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Protocol analyser

H04L 43/18

{using software, i.e. software packages (network security related monitoring H04L 63/1408)}
References
Limiting references

This place does not cover:

monitoring for network security

H04L 63/1408

Threshold monitoring
Definition statement

This place covers:

Monitoring if observed parameters or metrics are within upper or lower thresholds.

Protocol analysers
Definition statement

This place covers:

Devices able to capture data (i.e. cells, packets or frames) and "understand / parse / decode" the field structure of different networking protocols in a promiscuous mode (i.e. all the data they receive) and able to process the captured data for representing the parsed / decoded data fields along with their meanings of different packets specified by different networking protocols (e.g. Wireshark) in order to facilitate the analysis for a user.

media27.png

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Simple packet capture with probes

H04L 43/12

Protocol compliance testing

H04L 43/50

the monitoring system or the monitored elements being virtualised, abstracted or software-defined entities, e.g. SDN or NFV
Definition statement

This place covers:

Aspects covering operations specifically defined for monitoring or testing data switching networks for virtualised systems, virtualised network functions, virtualised entities and network slices, e.g. being performed by an orchestrator, OpenFlow controller, NFV-MANO entities and cloud managers.

Relationships with other classification places

As far as the virtualised monitoring system or monitored elements involve relevant aspects covered by other H04L 43/00 subgroups, these aspects are additionally classified under the relevant subgroups.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Fault Management

H04L 41/06

Testing arrangements
Definition statement

This place covers:

Testing of data networks, with specific focus on the following aspects:

Architectural aspects of testing: layout of the testing environment, design of the testing system, distribution of the testing nodes in the network at specific locations, devices dedicated for testing, or networking devices that have dedicated test modes.

Functional aspects of testing: benchmark testing, design of test scripts, test sequences, traffic patterns to be injected in the network system or device to be tested.

Testing groups of devices: testing groups of devices at once, for speeding-up the testing.

Compliance testing: testing whether a device complies to the specific protocol that it is supposed to adhere to.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Arrangements for detecting or preventing errors in the information received; testing correct operation

H04L 1/24

Alarm or event or notifications correlation; root cause analysis; by additionally acting on or stimulating the network after receiving notifications

H04L 41/0645

Active monitoring (e.g. heartbeat protocols or polling or ping or trace-route)

H04L 43/10

Protocol analysers

H04L 43/18

Testing of service level quality

H04L 43/55

Testing presence of Network Address Translation [NAT], e.g. STUN, TURN, MMUSIC/ICE

H04L 61/2575, H04L 61/2589

Arrangements for testing electric properties

G01R 31/00

Software testing in computer systems

G06F 11/3668

Line transmission systems; Monitoring; Testing

H04B 3/46

Transmission of information-carrying signals; Monitoring; Testing

H04B 17/00

Time-division multiplex systems; Provisions for broadband connections in integrated services digital network using frames of the Optical Transport Network [OTN] or using synchronous transfer mode [STM], e.g. SONET, SDH; Testing

H04J 2203/0062

Telephonic communication; Supervisory, monitoring, or testing arrangements in automatic or semi-automatic exchanges

H04M 3/22

Diagnosis, testing or measuring for television systems or their details

H04N 17/00

Selective content distribution; detecting features or characteristics in audio or video streams

H04N 21/4394, H04N 21/44008

Selecting arrangements for multiplex systems; Using optical techniques; Testing; Monitoring

H04Q 2011/0083

Testing of service level quality, e.g. simulating service usage
Definition statement

This place covers:

Testing the quality level of a service, e.g. by simulating or emulating service usage by active agents to automatically measure Service Level compliance, testing based on artificial traffic, artificial customer's behaviour.

Relationships with other classification places

The determination and monitoring of Service Level performance and of violations of Service Level requirements is covered by H04L 41/5009. Measuring the contribution of individual network components to actual Service Level is covered by H04L 43/091.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Network Service Management, e.g. ensuring proper service fulfilment according to agreements

H04L 41/50

Routing or path finding of packets in data switching networks (routing or path finding in wireless networks H04W 40/00)
References
Limiting references

This place does not cover:

Routing or path finding of packets in data switching networks specially adapted for wireless routing

H04W 40/00

Topology update or discovery
Definition statement

This place covers:

Details on network reconfiguration for routing purposes, topology database update and exchange, update of link metrics in a distributed routing system, conversion of physical to logical topology for routing.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Topology discovery and update for network management

H04L 41/12

Routing tree calculation

H04L 45/48

Topology issues related specifically to wireless networks

H04W 40/24

Ensuring consistency of routing table updates, e.g. by using epoch numbers
Definition statement

This place covers:

Arrangements to make sure that the routing table contained in each router corresponds to the latest available version.

Delayed use of routing table updates
Definition statement

This place covers:

Delay of the implementation of the just received updates, e.g. so that all nodes implement the update at the same time.

{Updating only a limited number of routers, e.g. fish-eye update}
Definition statement

This place covers:

Updating techniques in which update information is broadcast with a hop counter so that only nodes at a certain distance receive the update; region-wise or limited-scope updates.

{Details of "hello" or keep-alive messages}
Definition statement

This place covers:

Routing update or discovery using "hello" or "keep-alive" packets sent or broadcast by a specific router in order to inform the neighbouring routers of its presence or to verify that the neighbouring routers are still up and running.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Avoiding end of session, e.g. keep-alive, heartbeats, resumption message or wake-up for inactive or interrupted session

H04L 67/145

Dynamic adaptation of the update intervals, e.g. event-triggered updates
Definition statement

This place covers:

Conditions under which the exchange of routing table updates takes place.

by updating link state protocols
Definition statement

This place covers:

Details on updating link state protocols for routing purposes.

by updating distance vector protocols
Definition statement

This place covers:

Details on updating distance vector protocols for routing purposes.

Updating the topology between route computation elements, e.g. between OpenFlow controllers
Definition statement

This place covers:

Interaction between route computation elements for the purpose of routing topology update, e.g. between controllers located in different network domains.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Configuration of virtualised networks or elements, e.g. virtualised network function or Openflow elements

H04L 41/0895

Interdomain routing, e.g. hierarchical routing

H04L 45/04

Routes obligatorily traversing service-related nodes
Definition statement

This place covers:

Route determination in which at least one of the nodes that must be part of the route is selected based on the type of application to be routed.

for service chaining
Definition statement

This place covers:

Selection of paths in order to comprise nodes or devices that provide specific services to end users or end devices, e.g. according to a sequence of actions to be applied to the flow.

{Interdomain routing, e.g. hierarchical routing}
Definition statement

This place covers:

Inter-cluster routing Internet routing; provisions in routers for interdomain routing; inter LAN routing with bridges; routing in Hierarchical Networks; all hierarchical aspects of BGP and PNNI.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Cluster building

H04L 45/46

{Deflection routing, e.g. hot-potato routing}
Definition statement

This place covers:

Forwarding, by routing nodes of the received autonomous network data packets, without buffering in order to reduce traffic and network complexity. Hypercubes and hypertorus routing in multiprocessor networks such as the routing used for supercomputers.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Combinations of two or more digital computers

G06F 15/16

{Learning-based routing, e.g. using neural networks or artificial intelligence}
Definition statement

This place covers:

Routing with genetic algorithms, fuzzy logic, artificial intelligence (AI) for routing purposes, ants-routing.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Machine learning per se

G06N 20/00

{Routing in connection-oriented networks, e.g. X.25 or ATM}
Definition statement

This place covers:

Provisions for routing with virtual circuits; routing in Frame Relay.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Hierarchy definition for routing in ATM-PNNI

H04L 45/04

Virtualisation or emulation of application or operating system execution engines

G06F 9/455

Shortest path evaluation
Definition statement

This place covers:

Different techniques for the calculation of the shortest path based on any kind of single metric (Objective Functions) or metrics combination.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Function evaluation by approximation methods per se

G06F 17/17

by minimising delays
Definition statement

This place covers:

Using minimum path delay or latency (e.g. queuing delay, round-trip time) in order to determine the best route.

by minimising distances, e.g. by selecting a route with minimum of number of hops
Definition statement

This place covers:

Using the number of intermediate nodes between the source and the destination in order to determine the best route.

{Evaluation of link metrics (techniques for monitoring network metrics H04L 43/08)}
Definition statement

This place covers:

Applying a function to a basic parameter such as delay in order to create a new metric, e.g. delay statistics; refine a parameter to create a new metric. The link metric is obtained after operation of a link performance value, e.g. a link metric could be the average loss rate over a time interval.

References
Limiting references

This place does not cover:

Techniques for monitoring network metrics

H04L 43/08

{using a combination of metrics}
Definition statement

This place covers:

Details on using a combination of parameters to determine the best path, including constrained shortest path calculation. The parameter is a basic parameter or a combined/new parameter.

based on throughput or bandwidth
Definition statement

This place covers:

Routing based on minimum link metrics relating to available rate in the links; congestion, link occupancy.

{minimising geographical or physical path length}
Definition statement

This place covers:

Routing based on determining the paths having the minimum physical length

{based on intermediate node capabilities}
Definition statement

This place covers:

Using different parameters of intermediate routing nodes as a route calculation metric, e.g. processing or storage capabilities.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Battery capabilities in wireless routing

H04W 40/10

for finding disjoint paths
Definition statement

This place covers:

Determining whether two routes between the same end-points do not share nodes or links.

{with disjoint links}
Definition statement

This place covers:

Determining whether two routes between the same end-points do not share links.

{with disjoint nodes}
Definition statement

This place covers:

Determining whether two routes between the same end-points do not share nodes.

{Routing performance; Theoretical aspects}
Definition statement

This place covers:

Performance, stability and graph theory, e.g. Directed Acyclic Graph, DAG, Bellman-Ford, Dijkstra and other basic routing algorithms for path selection.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Function evaluation by approximation methods per se

G06F 17/17

Multipoint routing
Definition statement

This place covers:

Specific arrangements for supporting broadcast such as dedicated routing tables or route discovery for multipoint packets.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Broadcast in general

H04L 12/18

Shortcut routing, e.g. using next hop resolution protocol [NHRP]
Definition statement

This place covers:

Specific arrangements for shortcut routing, e.g. NHRP.

Loop-free operations
Definition statement

This place covers:

Routing arrangements for avoiding packets from travelling in loops, e.g. an identifier in a message is saved in a node to check if the same message is again passing the node; updating of a routing table is inhibited for a certain period of time, routing is only allowed in a certain direction.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Updating of a routing table, wherein the updated routing values are inhibited for a certain period of time

H04L 45/023

Spanning tree techniques

H04L 45/48

{Hop count for routing purposes, e.g. TTL}
Definition statement

This place covers:

Age, time to live or hop counting for broadcast or loop free, such as Layer 2 TTL, timestamp to age out.

{Alternate routing}
Definition statement

This place covers:

Routing techniques using different routes for communication between two nodes in which only one of the routes is used at a time; route diversity; primary and secondary routes; re-routing; 1:1 protection; link or path protection; shared link risk groups.

Multipath
Definition statement

This place covers:

Routing techniques using multiple routes between two nodes used simultaneously for load sharing or higher speed, including when involving packet fragmentation; redundant transmission, 1+1 and n:m path redundancy.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Load sharing/balancing (without additional routing features)

H04L 47/125

using M+N parallel active paths
Definition statement

This place covers:

Details on multipath routing using a different number of parallel active paths for redundancy purposes.

{Link aggregation, e.g. trunking}
Definition statement

This place covers:

Using a logical identity for the selection of a physical link among all possible physical links between two terminals or nodes; trunk group/Link aggregation.

using M:N active or standby paths
Definition statement

This place covers:

Details on multipath routing using a different number of active and standby paths for redundancy purposes.

{Route discovery packet}
Definition statement

This place covers:

Packets adapted for discovery of communication paths; scout packet; delay measuring packet; buffer occupancy measuring packet; path restoration message after route fault; traceroute; exploratory agent packet.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Arrangements for monitoring or testing data switching networks

H04L 43/00

RREQ-RREP for wireless routing

H04W 40/28

using route fault recovery
Definition statement

This place covers:

Recovery of communication routes after route fault or node failure.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Using network fault recovery

H04L 41/0654

Routing of multiclass traffic
Definition statement

This place covers:

Selection of a path for multiclass traffic.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Routing based on transmission quality or channel quality

H04W 40/12

Route determination based on requested QoS
Definition statement

This place covers:

Route selection based on a requested QoS, such as delay, bandwidth etc., in which the selected route has a minimum requested QoS.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Routing based on shortest path evaluation

H04L 45/12

{Route determination for signalling traffic}
Definition statement

This place covers:

Selecting a path specially adapted for signalling purposes, route determination for signalling traffic, setting up and reservation of special routes for signalling and control traffic.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Modification of handling priority for control packets, e.g. for ACK or signalling traffic

H04L 47/2466

{Route determination based on the nature of the carried application}
Definition statement

This place covers:

Selecting a path based on the nature of the application, e.g. browsing traffic HTTP, FTP traffic; content delivery networks using name based addressing.

{for real time traffic}
Definition statement

This place covers:

Route determination for real time traffic, e.g. voice and video.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Real-time or near real-time messaging, e.g. instant messaging [IM]

H04L 51/00

Network arrangements, protocols or services for supporting real-time applications in data packet communication

H04L 65/00

Selective video distribution

H04N 21/00

{Route determination based on user's profile, e.g. premium users}
Definition statement

This place covers:

Route determination based on the profile of the user or Service Level Agreement of the user; policy-based routing.

{Flooding (denial of service attacks H04L 63/1458)}
Definition statement

This place covers:

Techniques of routing in which packets are sent unconstrained into the network with a unicast address and only one destination is expected to receive the packets, the other nodes act as blind relays; limited flooding with a hop count.

References
Limiting references

This place does not cover:

Denial of service attacks

H04L 63/1458

{Source routing}
Definition statement

This place covers:

Routing techniques in which route preference (e.g. intermediate nodes) is declared in the packet or in which intermediate nodes record in a specific object the set of nodes through which a route establishment message passes and contents of record object are used for explicitly routing packets in subsequent messages.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Routing using backward learning

H04L 45/36

{Backward learning}
Definition statement

This place covers:

Routing based on learning address/port relationship from the passing traffic; learning the route followed from source to destination to use it again for the return traffic; update routing tables with learned relationship from passing traffic.

{Flow based routing}
Definition statement

This place covers:

Routing techniques in which all packets in a flow are routed in the same manner along a routing path.

{Wormhole routing}
Definition statement

This place covers:

Routing operation pipelining for faster processing, e.g. cut-through, streaming or on the fly.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Cut-through or Wormhole switching

H04L 49/251

Store and forward switching

H04L 49/252

Centralised routing
Definition statement

This place covers:

Routing in which a central entity collects (query/response) the routing metrics, calculates the appropriate routes and disseminates the routing information to the rest of the routers.

Distributed routing
Definition statement

This place covers:

Arrangements for routing performed in a distributed manner, e.g. each node calculates the appropriate routes and disseminates the routing information to the rest of the routers and no central entity is responsible for routing.

{Cluster building}
Definition statement

This place covers:

Routing in hierarchical networks; hierarchy definition; criteria for cluster membership.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Interdomain routing

H04L 45/04

Wireless routing for defining a routing cluster membership

H04W 40/32

Routing tree calculation
Definition statement

This place covers:

Routing techniques adapted to tree topologies; spanning tree.

using multiple routing trees
Definition statement

This place covers:

Routing aspects related to multiple trees, including definition, update and use of multiple tree topologies; multiple spanning trees.

using root node determination
Definition statement

This place covers:

Routing aspects related to determination of the route node in tree topologies.

using label swapping, e.g. multi-protocol label switch [MPLS]
Definition statement

This place covers:

Routing techniques using label swapping, e.g. multi-protocol label switching MPLS.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Traffic engineering

H04L 47/125

{Frame based}
Definition statement

This place covers:

Routing techniques using label swapping on frame-based transport, e.g. MPLS over IP based technology.

{Cell based}
Definition statement

This place covers:

Routing techniques using label swapping on cell-based transport, e.g. MPLS over Asynchronous Transfer Mode (ATM) networks.

{Label distribution}
Definition statement

This place covers:

Routing techniques detailing how to spread the labels among the nodes, e.g. Label Distribution Protocol (LDP).

Multiprotocol routers
Definition statement

This place covers:

Routing in networks having coexisting different routing protocols, e.g. RIP and OSPF, separated IPv4 and IPv6 routing stacks.

{Organization of routing tables}
Definition statement

This place covers:

Details of the information and format of the routing tables; special routing tables.

{Routing software}
Definition statement

This place covers:

Details on operating systems for routers, routing software architecture, scheduling of routing tasks software.

{Software download or update}
Definition statement

This place covers:

Details on download or update of software for routing, e.g. initialization of download of routing software or software for improving security of routing decisions, downloading of modified versions of routing software.

{Routing instructions carried by the data packet, e.g. active networks}
Definition statement

This place covers:

Data packets containing routing instructions, e.g. routing instructions to modify the routing tables.

Association of routers
Definition statement

This place covers:

Association of routers for multiple purposes, e.g. Active (working)-Standby (reserve) routers, load balancing or load sharing, multiple physical routers or multiple routing instances (hard or soft) in the same device behave as a single logical routing entity.

{Stackable routers}
Definition statement

This place covers:

Plurality of router instances (hard or soft) connected to, for example, the same backplane; physical association of routers, e.g. located in the same hardware chassis.

of virtual routers
Definition statement

This place covers:

Plurality of physical routers behaving as a logical unit, e.g. working in active/standby, Virtual Router Redundancy Protocol (VRRP).

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Virtualisation or emulation of application or operating system execution engines

G06F 9/455

Router architectures
Definition statement

This place covers:

Details concerning physical or hardware structure of a routing unit.

{Wavelength based (optical switching H04Q 11/0062)}
Definition statement

This place covers:

Routing specially adapted for optical networks, e.g. selection of the wavelength.

References
Limiting references

This place does not cover:

Optical switching

H04Q 11/0062

Informative references

Attention is drawn to the following places, which may be of interest for search:

Optical communications

H04B 10/00

Selecting arrangements for multiplex systems

H04Q 11/00

using an overlay routing layer
Definition statement

This place covers:

Multiple layers comprising a routing control layer specialized in topology update and routing policy determination, and a data layer under the routing layer, including separation of controlling and forwarding.

Splitting route computation layer and forwarding layer, e.g. routing according to path computational element [PCE] or based on OpenFlow functionality
Definition statement

This place covers:

Impact in the routing strategy of a separation between the routing control (computation) layer and the data (forwarding) layer. The route selection intelligence is (logically) centralised in software-based controllers (Path Computation Elements) that maintain a global view of the network topology, which appears to forwarding elements as a single, logical entity.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Network topology discovery or management

H04L 41/12

Interaction between route computation entities and forwarding entities, e.g. for route determination or for flow table update
Definition statement

This place covers:

Forwarding and updating of routing rules or flow table information between controllers and forwarding elements, e.g. routing table reconfiguration.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Network topology discovery or management

H04L 41/12

{Layer 2 routing, e.g. in Ethernet based MAN's}
Definition statement

This place covers:

Routing based on data link layer, e.g. using MAC address for routing.

{Pseudowire emulation, e.g. IETF WG PWE3}
Definition statement

This place covers:

Routing comprising emulation of services such as Frame Relay, ATM, ethernet, TDM and SONET/SDH over packet switched networks using IP or MPLS.

{Routing based on monitoring results}
Definition statement

This place covers:

Routing based on monitoring, measuring or observing of parameters needed for routing or how these parameters are measured.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Arrangements for monitoring or testing packet switching networks

H04L 43/00

{Routing based on the source address}
Definition statement

This place covers:

Route or next hop determination based on the sender's node address indicated in a data packet.

Address processing for routing
Definition statement

This place covers:

Details on address processing for routing purposes.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Network arrangements, protocols or services for addressing or naming

H04L 61/00

Routing in networks with a plurality of addressing schemes, e.g. with both IPv4 and IPv6
Definition statement

This place covers:

Routing between domains using different addressing schemes.

{Route cache; Operation thereof}
Definition statement

This place covers:

Details on route cache as a way to shorten table lookup operations, e.g. the complex lookup operation in the general table is done only on the first packet of a sequence, aging of route cache entries.

Address table lookup; Address filtering
Definition statement

This place covers:

Details on address table lookup and address filtering for routing purposes.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Network arrangements, protocols or services for addressing or naming

H04L 61/00

Multiple parallel or consecutive lookup operations (lookup operation involving Bloom filters H04L 45/7459)
Definition statement

This place covers:

Details of lookup operations that are conducted in parallel or in serial (cascading or series of consecutive lookups), using different lookup strategies.

References
Limiting references

This place does not cover:

Lookup operation involving Bloom filters

H04L 45/7459

using hashing
Definition statement

This place covers:

Details on routing techniques using hashing operations.

using Bloom filters
Definition statement

This place covers:

Use of Bloom filters in lookup operations as an alternative to the single hashing lookup.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Complex mathematical operations

G06F 17/10

{using content-addressable memories [CAM]}
Definition statement

This place covers:

Details on address table lookup operations and address filtering for routing purposes using content-addressable memories [CAM].

using longest matching prefix
Definition statement

This place covers:

Use of longest prefix match in routing operations.

Routing in software-defined topologies, e.g. routing between virtual machines
Definition statement

This place covers:

Routing in virtual network topologies where virtual machines are adapted to run routing protocols.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Virtualisation or emulation of application or operating system execution engines

G06F 9/455

Ingress point selection by the source endpoint, e.g. selection of ISP or POP
Definition statement

This place covers:

Details on ingress point selection by the source node for routing purposes.

Selection among different networks
Definition statement

This place covers:

Selection among different networks for routing purposes.

Dynamic network selection or re-selection, e.g. after degradation of quality
Definition statement

This place covers:

Dynamic network selection or re-selection for routing purposes, e.g. using artificial intelligence (AI).

Traffic control in data switching networks (arrangements for detecting or correcting errors in the information received H04L 1/00)
References
Limiting references

This place does not cover:

Traffic regulation in packet switching networks arrangements for detecting or correcting errors in the information received

H04L 1/00

Flow control; Congestion control
Definition statement

This place covers:

General aspects of flow control or congestion control which do not fall under a sub-class.

Glossary of terms

In this place, the following terms or expressions are used with the meaning indicated:

Flow control

Prevent a sender from overwhelming a receiver, traffic is controlled between a sender and receiver, only the sender controls the transmission rate

Congestion control

Prevent a sender from overwhelming the network, the network is prevented from becoming congested

Identifying congestion
Definition statement

This place covers:

Congestion monitoring to detect a degradation in network performance, using QoS parameters which indicate congestion or impending congestion. Typically exemplified by increased delays, jitter, packet losses or errors, increased retransmission rates. In response, congestion control or congestion avoidance is activated.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Maintenance or administration or management of packet switching networks; Bandwidth or capacity management, i.e. automatically increasing or decreasing capacities, e.g. bandwidth on demand

H04L 41/00, H04L 41/0896

Network monitoring of the performance of a network communications and QoS parameters

H04L 43/00, H04L 43/08

Routing; Evaluation of link metrics

H04L 45/00, H04L 45/12

{using a dedicated packet}
Definition statement

This place covers:

Either the receiver or intermediate nodes in the network can explicitly signal back to the sender that congestion has been identified using a dedicated packet rather than piggybacking a congestion indication in a data packet. The dedicated packet indicating congestion can be sent by a network controller, receiver, or intermediate node.

media29.png

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Maintenance or administration or management of packet switching networks

H04L 41/00

Network monitoring of the performance of a network communications and QoS parameters

H04L 43/00

Avoiding congestion; Recovering from congestion
Definition statement

This place covers:

Techniques for avoiding congestion including: monitoring ACKs and retransmissions at the sender, receiving feedback from the receiver. In response, the transmission rate, window size, etc. are adjusted.

media30.png

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Routing

H04L 45/00

Load balancing, e.g. traffic engineering

H04L 47/125

Wireless Routing

H04W 40/00

by diverting traffic away from congested entities
Definition statement

This place covers:

Localising congestion and selecting a different path/port/route with less congestion.

media31.png

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Routing

H04L 45/00

Routing to minimize delay

H04L 45/121

Routing based on performance – link metrics

H04L 45/123

Routing based on performance – bandwidth

H04L 45/125

Alternate routing – switching to a different path

H04L 45/22

Multipath routing – using multiple paths simultaneously

H04L 45/24

Wireless Routing

H04W 40/00

by balancing the load, e.g. traffic engineering
Definition statement

This place covers:

General field which relates to redistributing or balancing the flow to either avoid or recover from congestion. Load distribution can divert flow to different intermediate network nodes, paths, ports, queues or servers.

This code should be considered as a general one and applicable to H04L 45/00 and H04L 47/00 as well as to other fields in H04L.

media32.png

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Routing; Routing – Load balancing; Wireless Routing

H04L 45/00, H04L 45/24, H04W 40/00

Network-specific arrangements or communication protocols supporting networked applications; Load balancing among servers

H04L 67/00, H04L 67/1001

Wireless flow control; Wireless load balancing

H04W 28/00, H04W 28/08

by using congestion prediction
Definition statement

This place covers:

By monitoring to detect or forecast the onset of congestion and pre-emptively trigger congestion avoidance and recovery techniques.

media33.png

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Network monitoring of the performance of a network communications and QoS parameters

H04L 43/00

Prediction of resource usage

H04L 47/823

Real-time communications e.g. video streaming, voice conferencing QoS aspects

H04L 65/00, H04L 65/80

at the destination endpoint, e.g. reservation of terminal resources or buffer space
Definition statement

This place covers:

Techniques for congestion avoidance or recovery at a destination node.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Resource usage – mobile terminals

H04L 47/824

{in a LAN segment, e.g. ring or bus}
Definition statement

This place covers:

Techniques for congestion avoidance or recovery in a local area network, e.g. LAN segment, ring network or bus network.

media34.png

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Bus networks with decentralised control

H04L 12/413

Loop networks with decentralised control with asynchronous transmission, e.g. token ring, register insertion

H04L 12/433

LAN switches, e.g. ethernet switches

H04L 49/351

{by jamming the transmission media}
Definition statement

This place covers:

When a collision condition is detected, the station stops transmitting that frame, transmits a jam signal, and then waits for a random time interval before trying to resend the frame, e.g. CSMA/CD in Ethernet segments.

{in relation to multipoint traffic (arrangements for broadcast or multicast in data networks H04L 12/18)}
Definition statement

This place covers:

Flow and congestion control for multicast/multipoint flows, e.g. source based control, receiver driven layered approaches, exploitation of IGMP and multicast routing protocols, admission control, TCP friendly rate control.

References
Limiting references

This place does not cover:

Arrangements for multicast in data networks

H04L 12/18

Informative references

Attention is drawn to the following places, which may be of interest for search:

Arrangements for providing special services to substations for broadcast or conference, e.g. multicast with traffic restrictions for efficiency improvement, e.g. involving subnets or subdomains

H04L 12/1886

Routing multicast

H04L 45/16

Interaction among intermediate nodes, e.g. hop by hop
Definition statement

This place covers:

Neighbouring nodes cooperate to control the flow either using reservation, policies, PAUSE, backpressure, e.g. a congested node stops receiving packet from upstream node. This may cause the upstream node or nodes to become congested and rejects receiving data from above nodes. Backpressure is a node-to-node congestion control technique that propagate in the opposite direction of data flow.

media35.png

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Flow control or congestion control using information about buffer occupancy at either end or transit nodes

H04L 47/30

LAN switches, e.g. ethernet switches

H04L 49/351

Backpressure

H04L 49/506

Queuing arrangements

H04L 49/90

{End to end}
Definition statement

This place covers:

Congestion control and flow control is implemented between the sender and receiver.

at layers above the network layer (network arrangements for networked applications for scheduling or organising the servicing of application requests H04L 67/60)
Definition statement

This place covers:

Protocols adapted to include flow and congestion control techniques often in the context of client-server applications, e.g. TCP friendly rate control for UDP, TFRC. Application layer protocols adapted to support real-time communications: RTP, RTCP, RTSP, SIP etc.

When this scheme is crossed with H04L 67/00, it will yield documents concerning flow control in client/server communication.

Note: There is a specific subgroup dedicated to TCP related congestion control, see H04L 47/193 and H04L 69/163.

References
Limiting references

This place does not cover:

Network-specific arrangements or communication protocols supporting networked applications; For scheduling or organising the servicing of application requests

H04L 67/60

Informative references

Attention is drawn to the following places, which may be of interest for search:

Network monitoring of the performance of a network communications and QoS parameters

H04L 43/00

Network-specific arrangements or communication protocols supporting networked applications; For scheduling or organising the servicing of application requests

H04L 67/00, H04L 67/60

Application independent communication protocol aspects or techniques in packet data networks; Adaptation of TCP data exchange control procedures;Adaptation of UDP

H04L 69/00, H04L 69/163, H04L 69/164

at the transport layer, e.g. TCP related
Definition statement

This place covers:

Modifications or adaptations of classical TCP behaviour.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Monitoring; Delay

H04L 43/08, H04L 43/0852

Network delay

H04L 47/283

Slow start – only if it describes a modification to the standard slow start

H04L 47/37

TCP/IP; Adaptations of TCP exchange control procedure

H04L 69/16, H04L 69/163

Traffic management, e.g. flow control or congestion control adapting protocols for flow control or congestion control to wireless environment, e.g. adapting transmission control protocol [TCP]

H04W 28/0273

{Integration of transport layer protocols, e.g. TCP and UDP}
Definition statement

This place covers:

Congestion control techniques based on integration of transport layer protocols.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Application independent communication protocol aspects or techniques in packet data networks

H04L 69/00

Combined use of TCP and UDP

H04L 69/165

Traffic policing
Definition statement

This place covers:

Monitoring network traffic for compliance with a traffic contract and taking steps to enforce that contract at an ingress node. Traffic is monitored, metered and classified as being compliant/exceeding/violating the contract. The traffic contract can be described through various parameters: committed Information Rate CIR, Committed Burst Size CBS, and Excess Burst Size EBS. To enforce the contract, traffic can be discarded, flow control can be implemented (e.g. leaky buckets, traffic shaping and token buckets) or traffic can be marked as non-compliant, e.g. setting an ECN flag, DE, DSCP).

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Ensuring SLA

H04L 41/5019

Network monitoring of the performance of a network communications and QoS parameters

H04L 43/00

using leaky-bucket
Definition statement

This place covers:

A sender's packet is buffered in a leaky bucket. Packets are egressed from the leaky bucket at a constant rate. Consequently, bursty traffic is controlled and egressed as constant rate. Typically, the bucket is a finite queue that outputs at a finite rate.

media36.png

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Network monitoring of the performance of a network communications and QoS parameters

H04L 43/00

using token-bucket
Definition statement

This place covers:

A token bucket extends from the leaky bucket to allow flexibility for bursty traffic. Packets are egressed from the bucket in accordance with a deduction of corresponding tokens. Tokens are replenished at regular intervals.

media37.png

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Network monitoring of the performance of a network communications and QoS parameters

H04L 43/00

Traffic shaping
Definition statement

This place covers:

Traffic shaping (also known as packet shaping) is a bandwidth management technique that delays the flow of certain types of network packets in order to ensure network performance for higher priority applications. Traffic shaping limits the amount of bandwidth that can be consumed by certain types of applications.

media38.png

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Maintenance or administration or management of packet switching networks

H04L 41/00

Bandwidth or capacity management, i.e. automatically increasing or decreasing capacities, e.g. bandwidth on demand

H04L 41/0896

{Determination of shaping rate, e.g. using a moving window}
Definition statement

This place covers:

The shaping rate throttles the rate of packet transmission by setting a maximum bandwidth as a transmission rate or a maximum percentage of bandwidth for a queue or a forwarding class set. 

media39.png

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Packet Switching Systems

H04L 49/10

Quality of Service based

H04L 49/205

{Bit dropping}
Definition statement

This place covers:

Relates to voice traffic.

Traffic characterised by specific attributes, e.g. priority or QoS
Definition statement

This place covers:

Network arrangements for networked applications for scheduling or organising the servicing of application requests whereby quality of service or priority requirements are taken into account.

media40.png

for supporting different services, e.g. a differentiated services [DiffServ] type of service
Definition statement

This place covers:

Diff-Serv or differentiated services. Tags or labels (e.g. Class of Service CoS, Type of Service ToS, DSCP) in the packet header are used to provide a classification category of the type of traffic, wherein based on the tag or label, the packet receives a particular treatment or QoS in the network, for example: assured, expedited, default forwarding, class selection.

media41.png

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Special provisions for routing multiclass traffic

H04L 45/30

Route determination based on requested QoS

H04L 45/302

Real-time traffic
Definition statement

This place covers:

Flow control actions in relation to, for example, voice or video traffic.

media42.png

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Real-time bi-directional transmission of motion video data

H04N 7/14

Selective content distribution, e.g. interactive television or video on demand [VOD]

H04N 21/00

for supporting services specification, e.g. SLA
Definition statement

This place covers:

Service-level agreements [SLAs] are contracts that specify the performance parameters within which a network service is provided. The SLA might define parameters such as the type of service, data rate, and what the expected performance level is to be in terms of delay, error rate, availability, and network uptime.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

General aspects of SLA management

H04L 41/5003

Determining service level performance, e.g. measuring SLA quality parameters, determining contract or guarantee violations, response time or mean time between failure [MTBF]

H04L 41/5009

Ensuring SLA

H04L 41/5019

{Allocation of priorities to traffic types}
Definition statement

This place covers:

Congestion avoidance techniques adapted to perform allocation of priorities for each traffic type.

media43.png

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Priority, marking, classes

H04L 2012/5651

Quality of Service based

H04L 49/205

relying on flow classification, e.g. using integrated services [IntServ]
Definition statement

This place covers:

IntServ is an architecture that identifies the elements needed to specify and guarantee QoS in networks. IntServ architecture is adapted to determine and classify incoming flows to apply the suitable policy. Every node in the system implements IntServ, and every application that requires some kind of QoS guarantee has to make an individual reservation. Flow specifications describe what the reservation is for, while RSVP is the underlying mechanism to signal it across the network.

This field can be generally applied to the determination of the class of the flow according to a given criteria(e.g. QOS). Queuing actions or corresponding flow control actions can be applied thereafter.

media44.png

{using preemption}
Definition statement

This place covers:

Higher priority traffic (real-time, critical, public safety) is allowed to take precedence or pre-empt lower priority traffic when being scheduled, queued, allocated resources, or more generally when being communicated through the network.

media45.png

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Traffic management, e.g. flow control or congestion control using specific QoS parameters for wireless networks, e.g. QoS class identifier [QCI] or guaranteed bit rate [GBR]

H04W 28/0268

{Modification of priorities while in transit}
Definition statement

This place covers:

The priority of the packet is indicated in the packet and the priority in the packet is modified.

using signalling traffic
Definition statement

This place covers:

The priority indicated within the packet is not modified; rather priority is applied to signalling traffic, ACKs, etc.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Scheduling and prioritising arrangements

H04L 1/1854

Route determination for signalling traffic

H04L 45/304

Network-specific arrangements or communication protocols supporting networked applications for the provision of proxy services, e.g. intermediate processing or storage in the network for providing operational support to end devices by emulation, e.g. when they are unavailable, or by off-loading in the network

H04L 67/59

Adaptation of TCP data exchange control procedures

H04L 69/163

for supporting traffic characterised by the type of applications
Definition statement

This place covers:

Flow control actions that take into consideration the type of application.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Special provisions for routing multiclass traffic

H04L 45/30

Header parsing or analysis

H04L 69/22

involving identification of individual flows
Definition statement

This place covers:

Techniques to identify different flow types and apply flow control accordingly. Analysis of the packet header 5-tuple or statistical analysis of packets can be used to infer the particular flow type, e.g. small constant sized packets are indicative of voice.

Flow types include: Aggregated flows, Elephant or macro flows comprised of flowlets, sub-flows, mice flows, suspect or suspicious flows, audio, video etc.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Enhancement of application control based on intercepted application data

H04L 67/564

Header parsing or analysis

H04L 69/22

Mapping quality of service [QoS] requirements between different networks
Definition statement

This place covers:

Conversion of IP TOS to QCI.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Arrangements for connecting between networks having differing types of switching systems, e.g. gateways

H04L 12/66

Interdomain routing

H04L 45/04

Traffic management, e.g. flow control or congestion control

H04W 28/02

Traffic management, e.g. flow control or congestion control based on communication conditions

H04W 28/0231

Negotiating wireless communication parameters

H04W 28/18

Negotiating SLA [Service Level Agreement]; Negotiating QoS [Quality of Service]

H04W 28/24

with rate being modified by the source upon detecting a change of network conditions
Definition statement

This place covers:

Autonomous determination of congestion by the source endpoint in which there is no explicit feedback. Every source terminal or source node is able to determine the evolution of the congestion, e.g. by determining ACK packet loss or using techniques covered in other groups, such as H04L 47/50 or H04L 47/70.

using explicit feedback to the source, e.g. choke packets
Definition statement

This place covers:

The source endpoint is requested by the destination endpoint to apply rate correction actions. Explicit feedback can include feedback reports, e.g. RTCP, choke packets, e.g. a packet sent by a node to the source to inform it of congestion. Each router monitors its resources and the utilization at each of its output lines. Whenever the resource utilization exceeds the threshold value, which is set by the administrator, the router directly sends a choke packet to the source giving it a feedback to reduce the traffic. The intermediate nodes through which the packets have travelled are not warned about congestion.

media46.png

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Monitoring of the downstream path of the transmission network, e.g. bandwidth available

H04N 21/2402

Controlling the complexity of the video stream, e.g. by scaling the resolution or bitrate of the video stream based on the client capabilities

H04N 21/2662

Traffic management, e.g. flow control or congestion control based on conditions of the access network or the infrastructure network

H04W 28/0247

Traffic management, e.g. flow control or congestion control using buffer status reports

H04W 28/0278

Rate modification at the source after receiving feedback
Definition statement

This place covers:

Techniques for flow control in which source is adapted to modify its transmission rate after receiving feedbacks.

media47.png

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Reallocation of resources, renegotiation of resources, e.g. in-call triggered by the end-points

H04L 47/765

Backpressure

H04L 49/506

Flow control between communication endpoints

H04W 28/10

sent by intermediate network nodes
Definition statement

This place covers:

The intermediate node is requested by the destination endpoint to apply rate correction actions.

{Stopping or restarting the source, e.g. X-on or X-off}
Definition statement

This place covers:

Flow control action is based on interrupting the source of packet transmission until congestion is alleviated.

media48.png

sent by the destination endpoint (network streaming of media packets with control of the source by the destination H04L 65/613)
Definition statement

This place covers:

The destination node is adapted to send explicit feedback to the source node.

References
Limiting references

This place does not cover:

Network streaming of media packets with control of the source by the destination

H04L 65/613

Evaluation or update of window size, e.g. using information derived from acknowledged [ACK] packets
Definition statement

This place covers:

Recalculation of the congestion window to adapt to the network or destination endpoint situation.

This code is not meant for all documents that concerns windows based flow control.

media49.png

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Sliding window management

H04L 1/187

Adaptation of TCP data exchange control procedures

H04L 69/163

in relation to timing considerations
Definition statement

This place covers:

Flow control techniques taking into account time parameters, e.g. delays, latencies.

in response to processing delays, e.g. caused by jitter or round trip time [RTT]
Definition statement

This place covers:

Flow control techniques taking into account processing delays.

media50.png

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Network monitoring of the performance of a network communications and QoS parameters

H04L 43/00

Delay

H04L 43/0852

Round trip delays

H04L 43/0864

{Time to live}
Definition statement

This place covers:

Flow control techniques based on TTL.

media51.png

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Hop count for routing TTL

H04L 45/20

Self-organising networks, e.g. ad-hoc networks or sensor networks

H04W 84/18

{using a combination of thresholds}
Definition statement

This place covers:

Using plural thresholds triggering different actions when they are reached, for example, hysteresis.

media52.png

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Network monitoring of the performance of a network communications and QoS parameters

H04L 43/00

in combination with information about buffer occupancy at either end or at transit nodes
Definition statement

This place covers:

Flow control techniques taking into account buffer occupancy of nodes toward destination.

When giving this code, it is important to add the end-to-end or hop-by-hop codes if the feature is present.

media53.png

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Flow control or congestion control with hop by hop codes

H04L 47/17

Flow control or congestion control with end to end codes

H04L 47/18

Queueing arrangements many subclasses relating to buffers

H04L 49/90

Wireless buffer status reports

H04W 28/0278

by tagging of packets, e.g. using discard eligibility [DE] bits
Definition statement

This place covers:

Flow control techniques using tagging of packets.

media54.png

by discarding or delaying data units, e.g. packets or frames
Definition statement

This place covers:

Using discard policies for preventing congestion, e.g. partially discarding corrupted, excessively delayed or non-critical packets.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

One way delays

H04L 43/0858

Flow control between communication endpoints

H04W 28/10

{Discarding or blocking control packets, e.g. ACK packets}
Definition statement

This place covers:

Techniques for preventing congestion related to acknowledgment. Since acknowledgement are also the part of the load in network, the acknowledgment policy imposed by the receiver may also affect congestion. The receiver should send acknowledgement for N packets rather than sending acknowledgement for a single packet. The receiver should send an acknowledgment only if it has to send a packet or a timer expires.

Special actions on ACK traffic not related to delay or discard are classified in H04L 47/2466.

{with random discard, e.g. random early discard [RED]}
Definition statement

This place covers:

Flow control actions by using random early detection [RED], also known as random early discard or random early drop, e.g. queuing discipline for a network scheduler suited for congestion avoidance.

Various discard algorithms include: Weighted random early detection [WRED]; adaptive RED or active RED [ARED]; and Robust random early detection [RRED].

media55.png

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Network monitoring of the performance of a network communications and QoS parameters

H04L 43/00

Packet Switching Systems

H04L 49/10

Queueing in packet switching networks

H04L 49/90

using forward notification
Definition statement

This place covers:

Communication of the congestion information to the destination terminal. This is a kind of feedback to the destination.

ensuring sequence integrity, e.g. using sequence numbers
Definition statement

This place covers:

Flow control actions in combination with ensuring sequence integrity.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Arrangements for connecting between networks having differing types of switching systems, e.g. gateways

H04L 12/66

Alternate routing

H04L 45/22

Queuing arrangements

H04L 49/90

by embedding flow control information in regular packets, e.g. piggybacking
Definition statement

This place covers:

Flow control actions adapted to embedding specific flow control packets in data traffic packets.

by determining packet size, e.g. maximum transfer unit [MTU]
Definition statement

This place covers:

Flow control actions in combination with packet size determination, sometimes performed at the beginning of the communication.

media56.png

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Routing based on monitoring results

H04L 45/70

IP fragmentation or TCP segmentation aspects

H04L 69/166

{Dynamic adaptation of the packet size}
Definition statement

This place covers:

Dynamic adaptation of the packet size during communication.

{Slow start}
Definition statement

This place covers:

Modification of the starting window. This specific feature of TCP could appear in any other environment.

This code is used when the document describes an evolution from the standard procedure.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Adaptation of TCP data exchange control procedures

H04L 69/163

by adapting coding or compression rate
Definition statement

This place covers:

Flow control actions in combination with adapting coding or compression rates, e.g. in video transmission with the purpose of adapting the multimedia signal to the receiving terminal.

media57.png

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Media handling, encoding, streaming or conversion

H04L 65/60

Content on demand

H04L 65/612

Controlling the feeding rate to the network, e.g. by controlling the video pump

H04N 21/23805

{Credit based}
Definition statement

This place covers:

Flow control actions in combination with credits indicating availability or available buffer space of the receiver. Before data can be forwarded over a link, the sender needs to receive credits from the receiver.

At various times, the receiver sends credits to the sender indicating availability of buffer space for receiving data.

using split connections
Definition statement

This place covers:

Using a performance enhancing proxy access node that divides the end-to-end TCP connection between the client and the server into a multi-overlay-hop path where each overlay hop is an independent TCP connection, such that the RTT of each overlay hop is lower than the direct RTT between A and B, e.g. TCP splitting.

media58.png

by acting on aggregated flows or links
Definition statement

This place covers:

Flow control actions are applied to a bundle of links with the purpose of achieving an aggregate result. Corrective actions are applied to a set of links or flows corresponding to the same logical or physical entity.

media59.png

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Link aggregation, e.g. trunking

H04L 45/245

Assembling or disassembling of packets, e.g. segmentation and reassembly [SAR]
Definition statement

This place covers:

Flow control actions in combination with assembling or disassembling of packets.

using padding or de-padding
Definition statement

This place covers:

Flow control actions in combination with padding or de-padding of packets.

Queue scheduling
Definition statement

This place covers:

Packet scheduling when multiple queues are competing to transmit packets on a common link. A typical example of queue scheduling is illustrated below.

media60.jpg

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Packet Switching Systems

H04L 49/10

Input queuing

H04L 49/3018

Output queuing

H04L 49/3027

Shared queuing

H04L 49/3036

Virtual queuing

H04L 49/3045

Policing

H04L 49/503

Head of Line Blocking Avoidance

H04L 49/508

Queueing and buffering in packet switching networks

H04L 49/90

Plurality of buffers per packet

H04L 49/9021

Common buffer combined with individual queues

H04L 49/9036

by attributing bandwidth to queues
Definition statement

This place covers:

Scheduling policies that schedule the transmission of the data stored in the queue(s) taking into account the bandwidth consumed by the data. Such scheduling policies aim at optimizing the use of system bandwidth, by scheduling transmissions that neither underutilize nor saturate the transmission medium.

media61.png

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Bandwidth or capacity management, i.e. automatically increasing or decreasing capacities, e.g. bandwidth on demand

H04L 41/0896

{Static queue service slot or fixed bandwidth allocation}
Definition statement

This place covers:

Data in each queue are assured a portion of the total bandwidth as in the Weighted Fair Queueing scheduling method (see H04L 47/56) or the queue service slot (meaning the time that a queue is active each round) is fixed.

{Dynamic queue service slot or variable bandwidth allocation}
Definition statement

This place covers:

Schedulers which adapt the queue service slot (the time that a queue is active each round) or the bandwidth allocation in each service round based on different parameters. The queue service order can be fixed or variable and is classified under the group H04L 47/62.

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{Queue skipping}
Definition statement

This place covers:

H04L 47/524 is a special case of H04L 47/522, wherein the scheduler does not assign any bandwidth to a given queue.

by redistribution of residual bandwidth
Definition statement

This place covers:

In this case, there is a minimum guaranteed bandwidth per each queue and the residual bandwidth is redistributed among the queues.

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{Quantum based scheduling, e.g. credit or deficit based scheduling or token bank}
Definition statement

This place covers:

Scheduling in which each poll session is assigned a weight (quantum) of bits to be transmitted.

If the queue has less bits, a credit is assigned to said queue and quantum credit can be transmitted during the next poll (see also H04L 47/6265).

Token banks involve assigning tokens to the queues and storing said tokens in a finite capacity bank. The tokens assigned to a queue whose associated bank has reached its maximum capacity are assigned to another queue whose bank is below its capacity. Access to the resources is allowed if the queue has a predetermined number of tokens in its associated bank, otherwise it is denied.

{Minimum bandwidth guarantee}
Definition statement

This place covers:

The scheduler assigns a guarantee minimum bandwidth to each queue.

{Loss aware scheduling}
Definition statement

This place covers:

Scheduling taking into account the history of losses per flow or per class in order to prioritise the flows or classes accordingly. Changing the loss tolerance, value used for scheduling, of packets depending on whether or not another packet from the same stream has been scheduled for transmission before or after its deadline.

implementing delay-aware scheduling
Definition statement

This place covers:

Scheduling taking into account delay constraints of packets, for example, real time packets. Under this code disciplines in which packets are scheduled according to a system potential (also referred to as virtual time) are also covered. The scheduler uses this global function to compute timestamps which specify when packets should be served. Packets are scheduled in increasing order of the corresponding timestamps. The specific function used as system potential determines the delay and fairness properties.

If different priorities are involved, then the corresponding group H04L 47/24 is also used. For example, groups H04L 47/245 and H04L 47/2416 also apply.

{Attaching a time tag to queues}
Definition statement

This place covers:

Scheduling in which packets are grouped in buffers according to the corresponding session rate and only one timestamp is maintained per rate.

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{Attaching a deadline to packets, e.g. earliest due date first}
Definition statement

This place covers:

Scheduling in which each packet is assigned a timestamp for transmission, for example, earliest.

{Deadline varies as a function of time spent in the queue}
Definition statement

This place covers:

Excess bandwidth is used to try to equalize the delays of the connections.

{Calendar queues or timing rings}
Definition statement

This place covers:

Scheduling using calendar queues or timing rings.

A calendar queue is an ordered structure of bins representing possible values of timestamps in the system. The bins are ordered by increasing value of their timestamps. When the maximum difference between timestamps of backlogged sessions in the system is bounded, the calendar queue can become a circular queue where the bins can be reused as the time progresses. The bin associated with the minimum value must correspond with the value of the system potential at that time, and the total number of bins must be sufficient to cover the possible range of timestamps. Each bin is implemented as a list of pointers to individual connections. Every time a connection receives a new timestamp, it is linked to the corresponding bin.

The calendar queue can be automatically resized, i.e. the number of bins and the width of the bins (the number of possible timestamp values of a bin) can be changed depending on the distribution of backlogged connections in the bins. The granularity of the bins or slots in one calendar queue can be variable, for example, in the logarithmic calendar queue.

media65.png

media66.png

{Changing or combining different scheduling modes, e.g. multimode scheduling}
Definition statement

This place covers:

Changing the scheduling discipline upon an event such as congestion.

implementing hierarchical scheduling
Definition statement

This place covers:

Hierarchical integration of schedulers.

A hierarchical scheduler can be represented by a tree where the root node corresponds to a scheduler which multiplexes the packets on the physical link, each intermediate node corresponds to a scheduler at that level of the hierarchy, and the leaf nodes correspond to the allocated sessions. Each leaf is connected to the root through a single path of intermediate nodes.

The classes for the specific schedulers should be also given. If different types of schedulers are used, the class H04L 47/58 should be given also.

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media68.png

characterised by scheduling criteria
Definition statement

This place covers:

Various general aspects of queue scheduling.

{Arrangements for avoiding head of line blocking}
Definition statement

This place covers:

Scheduling techniques adapted to avoid Head of Line [HOL] Blocking, e.g. the first packet in a queue which is waiting for the corresponding output to be free prevents other packets from that queue to be transferred to the corresponding outputs which are free.

{Individual queue per connection or flow, e.g. per VC}
Definition statement

This place covers:

Scheduling techniques adapted to process each individual queue in a flow or connection.

{Individual queue per QOS, rate or priority}
Definition statement

This place covers:

Scheduling techniques adapted to consider an individual queue for each QoS class, rate or priority of traffic.

media69.png

{Queue service order}
Definition statement

This place covers:

Scheduling techniques adapted to consider the service order of the queues. The service order can be fixed, as in Round Robin scheduling method, or variable.

{Variable service order}
Definition statement

This place covers:

Scheduling techniques in which the service order of the queues is variable.

Therefore, if in the first round queues 1, 2 and 3 are served in that order, in the second round queue 3 could be served as first queue followed by 1 and 2. To be used in conjunction with H04L 47/625.

{Altering the ordering of packets in an individual queue}
Definition statement

This place covers:

Scheduling techniques adapted to change the ordering of packets in a queue, e.g. a buffer manager manages a sequence of pointers each referencing a separate cell of the buffer, the sequence of pointers being ordered to indicate the order in which the buffer manager has to write/read into/from the single cell.

{Modifications to standard FIFO or LIFO}
Definition statement

This place covers:

Scheduling techniques in which the standard FIFO or LIFO procedure for writing/reading data in the queue is modified under certain conditions.

for service slots or service orders
Definition statement

This place covers:

Scheduling techniques adapted to apply other criteria for service slot or service order than those covered by H04L 47/6205 - H04L 47/6245.

{queue load conditions, e.g. longest queue first}
Definition statement

This place covers:

Scheduling techniques in which the load of the queue is constantly monitored and the next scheduled queue is the queue with the highest load. One or more predetermined thresholds can be used and priority can be set for choosing between queues which are in the same condition.

In this case, the classes H04L 47/29 and H04L 47/30 should also be considered. Otherwise, the bandwidth, for example, number of packets read from a queue can be changed based on load condition of a specific queue.

{channel conditions}
Definition statement

This place covers:

Scheduling techniques where the order in which the respective queues are visited is chosen as a function of the propagation conditions on the transmission channel associated to each queue.

The same can apply to the bandwidth dedicated to each queue per service slot.

{past bandwidth allocation}
Definition statement

This place covers:

Techniques in which the scheduling of the queue is changed according to the previous bandwidth allocation. A credit (counter) system per queue is introduced. The history credit count of each queue is increased when data transmission from the queue is blocked and decreased when arbitration has been won on the basis of the history credit count. In this way, the reading sequence of the queues is determined.

{policing}
Definition statement

This place covers:

Scheduling techniques in which each flow is metered to determine whether its bitrate is below/over its guaranteed bitrate requirement, and based on the measurement, a scheduling weight is determined. The traffic queues are then scheduled according to the determined scheduling weights.

based on priority
Definition statement

This place covers:

Scheduling techniques in which the order in which the respective queues are visited is chosen according to the queue priority, often in combination with H04L 47/6215.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Individual queue per QoS, rate or priority

H04L 47/6215

based on packet size, e.g. shortest packet first
Definition statement

This place covers:

The scheduler takes into account the packet size.

{Provisions for avoiding starvation of low priority queues}
Definition statement

This place covers:

Scheduling techniques in which low priority queues are prevented for being empty.

Ensuring fair share of resources, e.g. weighted fair queuing [WFQ]
Definition statement

This place covers:

Scheduling techniques designed in order to achieve a fair sharing of resources among different users.

using multiple queues, one for each individual QoS, connection, flow or priority
Definition statement

This place covers:

Scheduling techniques which further organise packets having same QoS/connection/flow/priority into multiple queues.

This is a further subdivision with respect to H04L 47/6215.

Admission control; Resource allocation
Definition statement

This place covers:

The interaction between an endpoint and the network for ensuring resource availability for a requesting user.

A requested or negotiated resource can take many forms, for example, bandwidth, slots, buffer capacity or other transmission resources. Typically following negotiation, a reservation phase is performed before the actual communication is established, for example, call setup. Other aspects covered in this class is renegotiation, for example, bandwidth reallocation either requested by an already active user or by the ingress node network to adapt the available resources to serve new calls with higher priority.

In particular, it should be noted that the following classes have been allocated for network slicing applications:

Architecture

H04L 47/78

Service chaining and classification

H04L 47/2441

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Network dimensioning or reallocation of resources between areas of the network

H04L 41/00

Network fault recovery selecting new candidate element

H04L 41/0668

Bandwidth management and trading

H04L 41/0896

Routing

H04L 45/00

Alternate routing

H04L 45/22

Route fault recovery

H04L 45/28

Flow classification

H04L 47/2441

Resource allocation architecture

H04L 47/78

Protocols for multimedia access such as IMS or SIP

H04L 65/00

For peer-to-peer [P2P] networking; Functionalities or architectural details of P2P networks

H04L 67/104

Wireless load balancing or load distribution

H04W 28/08

Wireless resource allocation

H04W 72/04

Wireless resource scheduling

H04W 72/12

using reservation actions during connection setup
Definition statement

This place covers:

Admission control in which resources are reserved over the network in advance, usually at call setup time in order to assure a quality of service QoS. A traffic descriptor is provided so that the network can reserve enough bandwidth resource to handle the specified QoS.

at the destination endpoint, e.g. reservation of terminal resources or buffer space
Definition statement

This place covers:

Admission control ensuring that enough resources, e.g. buffer space, can be reserved at the receiver for the communication.

at intermediate nodes, e.g. resource reservation protocol [RSVP]
Definition statement

This place covers:

Admission control in which resources are reserved at the intermediate nodes, e.g. in the resource reservation protocol RSVP.

RSVP, described in RFC 2205, can be used by either hosts or routers to request or deliver specific levels of quality of service QoS for application data streams or flows. RSVP defines how applications place reservations and how they can relinquish the reserved resources once the need for them has ended. RSVP operation will generally result in resources being reserved in each node along a path.

Reserving resources in multiple paths to be used simultaneously (by balancing the load H04L 47/125)
Definition statement

This place covers:

Admission control in which the reservation is performed over a plurality of paths for the communication, for example for load balancing.

media70.jpg

References
Limiting references

This place does not cover:

Reserving resources by balancing the load

H04L 47/125

Informative references

Attention is drawn to the following places, which may be of interest for search:

Wireless load balancing

H04W 28/08

{for backup paths}
Definition statement

This place covers:

Admission control in which the reservation is performed for backup paths which are used in case of failure of the main path.

media71.jpg

measures in reaction to resource unavailability
Definition statement

This place covers:

Admission control reacting to the situations in which there are not enough resources for a connection, including a new connection or an existing connection, e.g. due to a failure.

Typical reactions are rejecting the connection or storing the request until resources become available. For existing connections and in case the reaction is a flow control or congestion control action as, for example, packet dropping, flow control subgroups under H04L 47/10 should be considered. An example is policing actions where H04L 47/20 would apply. This group could be used in combination with the group H04L 47/76 if the reaction is the reallocation of resources.

{Holding a request until resources become available}
Definition statement

This place covers:

Admission control in which an incoming request is held in a queue until the requested resources become available.

media72.jpg

{Reaction at the end points}
Definition statement

This place covers:

Admission control that includes reactions at the end nodes.

{Reaction in network}
Definition statement

This place covers:

Admission control that includes reactions in the network, e.g. when a new connection is accepted by diminishing the bandwidth reserved to other connections even if there is no sufficient bandwidth available.

media73.jpg

{Reaction triggered by a failure}
Definition statement

This place covers:

Admission control in which specific actions are performed as a reaction to a failure.

{Negotiation of resources, e.g. modification of a request}
Definition statement

This place covers:

Admission control in which, if the user requests cannot be satisfied due to lack of resources, the user resubmits (or is offered) an alternative request or is offered an alternative to the request, e.g. a connection at a bandwidth lower than the originally requested one.

media75.jpg

using dynamic resource allocation, e.g. in-call renegotiation requested by the user or requested by the network in response to changing network conditions
Definition statement

This place covers:

Admission control in which resources of existing connections are reallocated, e.g. to accommodate a new connection being triggered by an end-point, to upgrade a connection or to improve efficiency according to monitored patterns by the network.

For existing connections and in case the action is a flow control or congestion control/avoidance action, e.g. modification of packet priorities while in transit, flow control subgroups under H04L 47/10 should be considered. An example is policing actions where H04L 47/20 would apply.

triggered by the network
Definition statement

This place covers:

Admission control in which specific actions are initiated by the network.

media76.jpg

triggered by the end-points
Definition statement

This place covers:

Admission control in which specific actions are initiated by the end nodes.

media77.jpg

{after changing the attachment point, e.g. after hand-off}
Definition statement

This place covers:

Admission control in which specific actions are performed after changing of the attachment point such as an access node.

This group could be used in combination with H04L 47/783 (Distributed allocation of resources) when, for example, as a result of the hand-off there is a change of network domain.

media78.jpg

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Distributed allocation of resources, e.g. bandwidth brokers

H04L 47/783

Architectures of resource allocation
Definition statement

This place covers:

Admission control relevant to specific network architectures.

media79.png

{Centralised allocation of resources}
Definition statement

This place covers:

Admission control in which resources are allocated by a central unit.

{Hierarchical allocation of resources, e.g. involving a hierarchy of local and centralised entities}
Definition statement

This place covers:

Admission control performed by nodes which are related in a hierarchical configuration.

media80.png

media81.png

Distributed allocation of resources, e.g. bandwidth brokers
Definition statement

This place covers:

Admission control in which the allocation of resources is performed in a distributed way, e.g. by employing Bandwidth Brokers as agents that manage a domain and adapted to communicate with its adjacent peers, allowing end-to-end services to be constructed as a result of bilateral agreements.

media82.jpg

among multiple network domains, e.g. multilateral agreements
Definition statement

This place covers:

Admission control in which the allocation of resources is performed within multiple network domains allowing end-to-end services to be constructed as a result of multilateral agreements.

{Mapping reservation between domains}
Definition statement

This place covers:

Admission control in which the allocation of resources comprises inter-domains correspondence of reservations.

media83.jpg

media84.jpg

{Bandwidth trade among domains}
Definition statement

This place covers:

Multi-domain admission control in which the allocation of resources comprises bandwidth trade among domains.

media85.jpg

media86.png

{Autonomous allocation of resources}
Definition statement

This place covers:

The allocation of resources is done in an autonomous way by, e.g. an access point. The access point is responsible for the admission of new requests based on the current allocation of resources.

Actions related to the user profile or the type of traffic
Definition statement

This place covers:

Reservation actions depending on the type of traffic, e.g. real time vs. non-real time traffic, quality of service, priority, application dependent etc. or user, e.g. service level agreement, SLA.

{Real time traffic}
Definition statement

This place covers:

Resource allocation is done with preference to real time traffic in case of mixed real time and non-real time traffic, due to the sensitivity of the real time traffic to delay.

media87.jpg

{Application aware}
Definition statement

This place covers:

Allocation of resources or requesting of an access based on the application that is going to use the resources/access.

The bandwidth allocation problem becomes more difficult in multiservice networks that have a large variety of different applications, each one with different requirements in terms of bandwidth, duration or delay and information loss.

media88.jpg

{QOS or priority aware}
Definition statement

This place covers:

Allocation/reservation of resources based on specific QoS parameters requested by the connection.

media89.jpg

{Broadcast or multicast traffic}
Definition statement

This place covers:

Allocation/reservation for broadcast and multicast traffic.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Multicast in flow control

H04L 47/15

Multicast or broadcast media

H04L 65/611

Resource management for broadcast services

H04W 72/005

{User-type aware}
Definition statement

This place covers:

Allocation/reservation of resources is based on the type of user profile which is specified by the service level agreement SLA.

media90.jpg

{Miscellaneous aspects}
Definition statement

This place covers:

Other admission control aspects not covered by the previous subgroups.

{Prioritising resource allocation or reservation requests}
Definition statement

This place covers:

Prioritisation of the resource allocation/reservation requests.

media91.png

{Collecting or measuring resource availability data}
Definition statement

This place covers:

Prioritisation of the resource allocation/reservation requests.

media92.jpg

{Prediction of resource usage}
Definition statement

This place covers:

The allocation of resource is made by taking into account the effects that the resources to be allocated will have on the whole system.

media93.png

{Applicable to portable or mobile terminals}
Definition statement

This place covers:

Resource allocation/reservation wherein a portable or mobile terminal is involved.

{Involving tunnels, e.g. MPLS}
Definition statement

This place covers:

Resource allocation/reservation in networks using packet encapsulation techniques, e.g. MPLS or mobile IP networks.

media94.png

{Involving periods of time}
Definition statement

This place covers:

Resource allocation/reservation taking into account time parameters or performed in different periods of time, e.g. sending first data with high priority and at a later point in time data with less priority.

The class can also be used for resource reservation policies that vary with the time.

media95.jpg

{Aggregation of resource allocation or reservation requests}
Definition statement

This place covers:

Admission control in which the resource reservations are aggregated and sent to the node that requested the reservation.

media96.jpg

{Allocation of resources per group of connections, e.g. per group of users}
Definition statement

This place covers:

Admission control in which the allocation of resources is performed in relation to a group of connections.

media97.png

media98.png

media99.png

{Topology based}
Definition statement

This place covers:

Admission control in which the allocation of resources is based on a particular topology or in relation to the change of topology of the network.

media100.jpg

based on usage prediction
Definition statement

This place covers:

Admission control in which the allocation of resources is based on predicted usage of said resources.

Packet switching elements
References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Packet switching elements selecting arrangements for multiplex arrangements using optical switching

H04Q 11/0001

characterised by the switching fabric construction
Definition statement

This place covers:

Construction of the interconnect, or switching fabric or switching network, which connects every input port of the switch to every output port of the switch.

Interconnection of switching modules
Definition statement

This place covers:

Interconnection of the basic switching modules that are part of a switch fabric.

A switch fabric is built of basic switching building blocks, i.e. the switching modules.

A switching module is the basic unit of the switch fabric. It can be implemented in a single integrated circuit element or on a printed circuit board. The routing information of the incoming packet is analysed at the input port, and the cell is then directed to the correct output port (outlet). In general, the switching element consists of an interconnection network, an IC (input controller) for each incoming line and an OC (output controller) for each outgoing line. The OC transports cells which have been received from the interconnection network toward the destination. The IC and OC are coupled by the interconnection network.

Support for services
Definition statement

This place covers:

Details of specific features of packet switches for support of certain services, e.g. application services or a certain quality of service (QoS).

{Peripheral units, e.g. input or output ports}
Definition statement

This place covers:

Details of the peripherals units of a switch comprising functionalities taking place either between the end of the input link and the switching fabric, or between the switching fabric and the output link.

Switches specially adapted for specific applications
Definition statement

This place covers:

Packet switches, routers or bridges which are designed to support specific applications or protocols, e.g. LAN switches, Fibre Channel switches.

Constructional details, e.g. power supply, mechanical construction or backplane
Definition statement

This place covers:

Details of the constructional aspects of a packet switch.

The constructional details may not only be mechanical but may also relate to clock distribution, connectors, backplane distribution, etc.

Arrangements for providing or supporting expansion
Definition statement

This place covers:

Details concerning the upgrading of a switch, expanding a switch, e.g. a switch which is already in operation needs to be upgraded in terms of adding more ports to the switch or other upgrades concerning the switching fabric, the processing capacity of the controller or the number of line cards.

Overload detection or protection within a single switching element
Definition statement

This place covers:

Details concerning all functions within a packet switch that are used to detect an overload situation and/or to protect the packet switch from the negative consequence of degraded throughput due to overload, including functions used to prevent failure of the switch or errors in the switch, such as loss of packets, due to overload.

The overload may be either at the packet or at the call control level. It may be detected in any part of the switch, peripherals, switching fabric, control.

The most common overload situation of packet switches is the burst arrival of more packets than can be handled by the switch. This results in packets being discarded or a malfunction of the entire switch. However, other reasons for overload do exist, for instance the control plane for connection oriented packet switches (e.g. ATM switches) may receive more signalling messages than can be processed.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Diverting traffic away from congested spots

H04L 47/122

Load balancing

H04L 47/125

Congestion Prediction

H04L 47/127

Reactions to storage capacity overflow

H04L 49/9084

Replacing packets in a storage arrangement, e.g. pushout

H04L 49/9089

Prevention, detection or correction of errors
Definition statement

This place covers:

Details concerning prevention, detection and corrections of errors such as packet loss, switch failure, internal routing errors.

Software-defined switches
Definition statement

This place covers:

Switches specially adapted for software-defined operations in cooperation with SDN controllers in network structures that centralise network intelligence in one network component, e.g. SDN controller, and separate the forwarding process or data plane from the routing process or control plane.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Updating the topology between route computation elements, e.g. between OpenFlow controllers

H04L 45/036

Splitting route computation layer and forwarding layer, e.g. routing according to path computational element [PCE] or based on OpenFlow functionality

H04L 45/645

Interaction between route computation entities and forwarding entities, e.g. for route determination or for flow table update

H04L 45/655

Re-configuration of fast packet switches
Definition statement

This place covers:

Details concerning aligning the physical properties of the switch with the control software of that particular switch as an activity that is either executed by the switch itself (e.g. by the control software) or via a connected operation and maintenance system.

This implies that prior to the (re-)configuration of the switch, a change in the hardware structure of the switch has taken place. Such a change may comprise an addition or removal of hardware, for instance a line card or a switch card, the change of status of availability of some hardware, for instance due to a failure. Another reason can, for instance, be the need to expand the switch or to increase its functionality.

{Virtual switches}
Definition statement

This place covers:

Details concerning switching functionalities implemented as software programs that allows communications between virtual machines.

A virtual switch does more than just forward data packets. It can intelligently direct communication on the network by inspecting packets before passing them on. Some vendors embed virtual switches right into their virtualisation software, but a virtual switch can also be included in a server's hardware as part of its firmware.

Apart from the pure software implemented virtual switch, there are hybrid virtual switches comprising a real physical switching fabric interconnecting physical machines with a network. The control software of the switch implements virtual ports, i.e. emulates multiple logical ports on a physical port. This can have advantages if connections have to be moved from one physical port to another physical port and it also seems to have advantages in load balancing within the switch.

Another type of virtualisation is the provision of a logical switch or cluster switch that emulates a single switch on a plurality of physical switches.

Buffering arrangements
Definition statement

This place covers:

Queueing arrangements in packet switching networks, buffer allocation to packets, e.g. memory location (internal, external), buffer pools, memory partition to adapt to packet size, linked list of buffers.

NIC-mainframe interface

Intermediate buffering before the packet is transferred to the packet memory in the mainframe. Intermediate FIFO, circular list of descriptors, early interrupt after a number of bits has arrived, etc. In relation to those functions you will find also features like detection of too large, too short packets or CRC control.

When packets reach a store-and-forward unit they have to be temporarily buffered until the forwarding decision is made by the routing engine.

User-to-user messaging in packet-switching networks, transmitted according to store-and-forward or real-time protocols, e.g. e-mail
Definition statement

This place covers:

Message switching systems in data switching networks. A message switching system is a system that switches messages on the application layer in the user plane. The messages have one or more individually identified recipients, although a user may have defined them to be part of a distribution list.

Examples:

Any electronic mail (email) systems and instant messaging (IM) systems

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Message passing systems for program control, e.g. messaging middleware

G06F 9/546

Computer aided management of electronic mail, such as the handling of e-mail on a local workstation

G06Q 10/107

With interactive means for internal management of messages

H04M 1/7243

Voice mail systems for telephonic communication

H04M 3/5307

Client devices for e-mailing in television systems

H04N 21/4786

Packet switching elements (selecting arrangements for multiplex arrangements using optical switching

H04Q 11/0001

Messaging specially adapted for wireless communication networks, e.g. SMS

H04W 4/12

Messaging specially adapted for wireless communication networks, e.g. SMS

H04W 88/184

using automatic reactions or user delegation, e.g. automatic replies or chatbot-generated messages
Definition statement

This place covers:

Any system or technique for creating and sending automatic replies to messages.

Real-time or near real-time messaging, e.g. instant messaging [IM]
Definition statement

This place covers:

Instant messaging is data exchange in real-time between at least two end users connected to a packet-switching network where the users can be aware of the identity and the presence of the other party or parties.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Messaging using presence information

H04L 51/043

Messaging combined to or interacting with other services or applications

H04L 51/046

Network arrangements or protocols for real-time communications

H04L 65/00

Presence management and presence servers as such

H04L 67/54

using or handling presence information
Definition statement

This place covers:

Instant Messaging in which user presence information is used for the message exchange.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Use or manipulation of presence information in messaging presence management

H04L 67/54

Interoperability with other network applications or services
Definition statement

This place covers:

Instant Messaging combined or interacting with other applications, which may be real-time or not.

Message adaptation to terminal or network requirements
Definition statement

This place covers:

Any manipulation of the message while in transit between the sender and the recipient for optimizing its delivery and display.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Networked arrangements for intermediate processing of conversion or adaptation of application content or format

H04L 67/565

Content adaptation, e.g. replacement of unsuitable content
Definition statement

This place covers:

Content adaptation for body or attachments. This can include the deletion of unwanted parts of the message, e.g. parental guidance, or multimedia data, the augmentation of the message or the replacement of data with links or summaries.

Format adaptation, e.g. format conversion or compression
Definition statement

This place covers:

Format adaptation, conversion or compression of a part of message of the entire message, e.g. changing a picture from BITMAP to JPEG format or text-to-speech conversion, changing message protocol. Although this may lead to loss of information due to different compression techniques or content that cannot be converted, the content is intentionally adapted, but any loss of information (due to the examples listed) is not intentional, and can be attributed to the adaptation (translation).

characterised by the inclusion of specific contents
Definition statement

This place covers:

Exchange of messages including content other than plaintext.

Annexed information, e.g. attachments
Definition statement

This place covers:

The attachment to a message that impacts transmission and/or handling of the message in the network.

Multimedia information
Definition statement

This place covers:

Messages including multimedia data which impact transmission and/or handling of message in the network.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Network arrangements or protocols for real-time communication

H04L 65/00

Voice messaging in telephonic communication using automatic or semi-automatic exchanges with non-audio components

H04M 3/5307

Commands or executable codes
Definition statement

This place covers:

Messages including links, URLs, executable codes, etc. to be executed either at an intermediate node or at the recipient.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Networked applications for remote control or remote monitoring of the application

H04L 67/025

Networked applications involving the movement of software or configuration parameters

H04L 67/34

Computer aided management of electronic mail

G06Q 10/10

Monitoring or handling of messages
Definition statement

This place covers:

Message monitoring and processing over the network.

using filtering or selective blocking
Definition statement

This place covers:

Blocking or partial filtering of messages based on predetermined criteria, e.g. based on the age of the message(s).

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Message adaptation to remove unwanted content

H04L 51/063

Firewalls and in particular filtering policies

H04L 63/0227

Malware detection or handling

G06F 21/56

Access security using filters or firewalls in wireless networks

H04W 12/088

using selective forwarding
Definition statement

This place covers:

Redirection of messages by an intermediate network node, e.g. a server, either for delivery optimisation especially based on network conditions and user profile.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

For profiles in general

H04L 67/306

Handling conversation history, e.g. grouping of messages in sessions or threads
Definition statement

This place covers:

  • Grouping messages in conversations
  • Forking conversations
  • Keeping track of conversations
using geographical location information, e.g. messages transmitted or received in proximity of a certain spot or area
Definition statement

This place covers:

Transmission or handling of the message in the network based on the location of the sender's and/or recipient's terminal.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Protocols for adapting network applications to user terminal location

H04L 67/52

Services specially adapted for wireless communication networks making use of the location of users or terminals

H04W 4/02

providing notification on incoming messages, e.g. pushed notifications of received messages
Definition statement

This place covers:

Alternative means for notifying a user that a message has been received.

Examples:

  • Notification that a message has been received by the server;
  • Notification of pre-defined events;
  • Notification on a wearable device.

Alternative means includes an out-of-band communication channel, an audible alert, a visual alert or a vibration alert.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Execution arrangements for user interfaces

G06F 9/451

Computer aided management of electronic mail

G06Q 10/10

User interfaces specially adapted for cordless or mobile telephones

H04M 1/724

Delivery according to priorities
Definition statement

This place covers:

Scheduling (both delaying or prioritising) message transmission depending of determined priority levels to guarantee a better user service.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Networked applications for intermediate processing whereby quality of service or priority requirements are taken into account

H04L 67/61

Reliability checks, e.g. acknowledgments or fault reporting
Definition statement

This place covers:

Informing the sender of a message about the correct reception of the message by the recipient, or on the missed or partial reception of the message.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Generation of monitoring or testing reports

H04L 43/06

for tracking messages
Definition statement

This place covers:

Detecting and reporting the progress of messages along the network.

Mailbox-related aspects, e.g. synchronisation of mailboxes
Definition statement

This place covers:

Message storage, synchronisation, categorisation and retrieval.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Computer aided management of electronic mail

G06Q 10/107

Message addressing, e.g. address format or anonymous messages, aliases
Definition statement

This place covers:

Hiding, modifying, retrieving, converting addresses of messages.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Arrangements and protocols for addressing and naming

H04L 61/00

for supporting social networking services
Definition statement

This place covers:

Messages exchanged over one or more social networks.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Social network management and organisation

G06Q 50/01

Unified messaging, e.g. interactions between e-mail, instant messaging or converged IP messaging [CPM]
Definition statement

This place covers:

Messages exchanged and accessed by the users through different platforms, protocols, applications.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Instant messages format conversion

H04L 51/066

Message adaptation for wireless communication
Definition statement

This place covers:

Messaging system adapted to the wireless structure of the network, as well as to its advantages and its constraints (e.g. intermittent network connections or bandwidth constraints including SMS and MMS.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Services specially adapted for wireless communication networks Messaging; Mailboxes;

H04W 4/12

Short messaging services

H04W 4/14

Messaging devices, e.g. message centre

H04W 88/184

Network arrangements, protocols or services for addressing or naming
Definition statement

This place covers:

The following aspects of addressing and naming in data networks:

  • Conversion and mapping of addresses, which includes mapping between different types of addresses, e.g. ARP or mapping between telephone numbers and IP addresses and mapping between the same type of addresses, e.g. NAT;
  • Directories and name-to-address resolution, e.g. DNS, LDAP, X.500, address books;
  • Allocation of addresses, e.g. DHCP;
  • Logical names, in particular aspects relating to the registration, conversion and structure of e.g. domain names, e-mail addresses, SIP-URIs etc.;
  • Non-standard use of addresses implementing a special functionality, e.g. QoS, billing etc.
References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Data switching networks; Arrangements for providing special services to substations for broadcast or conference

H04L 12/18

Data switching networks characterised by a path configuration; Home automation networks

H04L 12/2803

Exchanging configuration information on appliance services in a home automation network

H04L 12/2807

Data switching networks characterised by a path configuration; Bus networks

H04L 12/40

High-speed IEEE 1394 serial bus

H04L 12/40052

Data switching networks characterised by a path configuration; Interconnection of networks using encapsulation techniques, e.g. tunneling

H04L 12/4633

Arrangements for maintenance or administration or management of packet switching networks using standardised network management protocols

H04L 41/0213

Arrangements for maintenance or administration or management of packet switchingnetworks; Configuration management of network or network elements

H04L 41/08

Routing or path finding of packets in data switching networks

H04L 45/00

Message switching systems, e.g. electronic mail systems

H04L 51/00

Network architectures or network communication protocols for network security for separating internal from external traffic, e.g. firewalls

H04L 63/02

Network architectures or network communication protocols for network security for separating internal from external traffic; Firewall traversal, e.g. tunnelling or creating pinholes

H04L 63/029

Network architectures or network communication protocols for network security for providing a confidential data exchange among entities communicating through data packet networks

H04L 63/04

Network architectures or network communication protocols for network security for supporting authentication of entities communicating through a packet data network

H04L 63/08

Network arrangements or protocols for real-time communications

H04L 65/00

Network arrangements or protocols for real-time communications; Signalling, control or architecture; Session control; Registration

H04L 65/1073

Network-specific arrangements or communication protocols supporting networked applications in which an application is distributed across nodes in the network for accessing one among a plurality of replicated servers, e.g. load balancing

H04L 67/1001

Network-specific arrangements or communication protocols supporting networked applications adapted for proprietary or special purpose networking environments

H04L 67/12

Network-specific arrangements or communication protocols supporting networked applications involving the movement of software and/or configuration parameters

H04L 67/34

Network-specific arrangements or communication protocols supporting networked applications; Service discovery or service management

H04L 67/51

Network-specific arrangements or communication protocols supporting networked applications; Presence management

H04L 67/54

Network-specific arrangements or communication protocols supporting networked applications for the provision of proxy services, e.g. intermediate processing or storage in the network

H04L 67/56

Protocols for interworking or protocol conversion

H04L 69/08

Electric or fluid circuits specially adapted for vehicles for supply of electrical power to vehicle subsystemsusing multiplexing techniques

B60R 16/0315

Accessing, addressing or allocating within memory systems or architectures

G06F 12/00

Bus transfer protocol, e.g. handshake; Synchronisation

G06F 13/42

Information retrieval using distributed data base systems

G06F 16/27

Information retrieval from the Internet by using information identifiers, e.g. URLs

G06F 16/955

Administration, e.g. office automation or reservations

G06Q 10/00

Commerce, e.g. shopping or e-commerce

G06Q 30/00

Telephone directories in user terminals

H04M 1/27

Directory assistance systems

H04M 3/4931

Interconnection arrangements between switching centres

H04M 7/00

Details of addressing, directories or routing tables of networks other than PSTN/ISDN providing telephone service, e.g. Voice over Internet Protocol

H04M 7/0075

Details of addressing, directories or routing tables for working between exchanges having different types of switching equipment, where the types of switching equipment comprises PSTN/ISDN equipment and switching equipment of networks other than PSTN/ISDN,

H04M 7/128

Processing of mobility data, Registration at HLR or HSS

H04W 8/04

Network data management; Mobility data transfer

H04W 8/08

Network addressing or numbering for mobility support

H04W 8/26

Registration; Multiple registrations, e.g. multihoming

H04W 60/005

Network layer protocols in wireless communication networks, e.g. mobile IP

H04W 80/04

Network topologies; Self-organizing networks, e.g. ad-hoc networks or sensor networks

H04W 84/18

Devices specially adapted for wireless communication networks

H04W 88/00

Devices specially adapted for wireless communication networks adapted for operation in multiple networks

H04W 88/06

Special rules of classification
Synonyms and Keywords

In patent documents, the following abbreviations are often used:

ARP

Address Resolution Protocol

DHCP

Dynamic Host Configuration Protocol

DNS

Domain Name System

GRUU

Globally Routable UA URI

LDAP

Lightweight Directory Access Protocol

NAT

Network Address Translation

RARP

Reverse Address Resolution Protocol

STUN

Session Traversal Utilities for NAT

TURN

Traversal Using Relay NAT

URI

Uniform Resource Identifier

Mapping addresses
Definition statement

This place covers:

The pairing of addresses, which require a mapping or a conversion in the network. Specific examples are given in the subgroups.

The mapping of names to addresses is classified in the subgroups of H04L 61/45.

of different types
Definition statement

This place covers:

The pairing of addresses of different type which require a mapping or conversion in the network in contrast to mapping of addresses of the same type, e.g. NAT, which is classified in H04L 61/25.

Special rules of classification

Directory aspects should be classified in the subgroups of H04L 61/45. Preferably the types of addresses involved should be classified using the indexing scheme. Mapping of addresses of the same type, e.g. NAT, is classified in H04L 61/25.

across network layers, e.g. resolution of network layer into physical layer addresses or address resolution protocol [ARP]
Definition statement

This place covers:

The pairing of addresses across network layers, e.g. the pairing of an IP address and a MAC address (ARP).

Examples: IETF RFC 826 (ARP), IETF RFC 6830 (LISP).

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Data switching networks characterised by a path configuration; Interconnection of networks using encapsulation techniques, e.g. tunnelling

H04L 12/4633