Skip over navigation
Outline
Indent Level
Color Curly Brackets (indicating CPC extensions to IPC)

CPC
COOPERATIVE PATENT CLASSIFICATION
Collapse
CODING OR CIPHERING APPARATUS FOR CRYPTOGRAPHIC OR OTHER PURPOSES INVOLVING THE NEED FOR SECRECY (secret transmission H04K; arrangements for secret telegraphic communication H04L 9/00)
Collapse
Apparatus or methods whereby a given sequence of signs, e.g. an intelligible text, is transformed into an unintelligible sequence of signs by transposing the signs or groups of signs or by replacing them by others according to a pre-determined system (cryptographic typewriters G09C 3/00)
G09C 1/02
.
by using a ciphering code in chart form
G09C 1/04
.
with sign carriers or indicators moved relative to one another to positions determined by a permutation code, or key, so as to indicate the appropriate corresponding clear or ciphered text
Collapse
G09C 1/06
.
wherein elements corresponding to the sign making up the clear text are operatively connected with elements corresponding to the signs making up the ciphered text, the connections, during operation of the apparatus, being automatically and continuously permuted by a coding or key member
G09C 1/08
. .
the connections being mechanical
Collapse
G09C 1/10
. .
the connections being electrical
G09C 1/12
. . .
comprising contact-bearing permutation discs
G09C 1/14
. .
involving removable or interchangeable coding numbers, e.g. master tapes, punched cards
Collapse
Typewriters for ciphering or deciphering cryptographic text (marking record carriers G06K)
G09C 3/02
.
with auxiliary keys or keyboards acting on the original key or keyboards
Collapse
G09C 3/04
.
wherein the operative connections between the keys and the type-bars are automatically and continuously permuted, during operation, by a coding or key member
G09C 3/06
. .
the connections being mechanical
G09C 3/08
. .
the connections being electrical
G09C 3/10
. .
involving removable or interchangeable coding members, e.g. master tapes, punched cards
Ciphering apparatus or methods not provided for in the preceding groups, e.g. involving the concealment or deformation of graphic data such as designs, written or printed messages
This page is owned by Office of Patent Classification.
Last Modified: 10/10/2013