| US 7,466,687 B2 | ||
| Packet classification using modified range labels | ||
| Claude Basso, Raleigh, N.C. (US); Jean Louis Calvignac, Cary, N.C. (US); Gordon Taylor Davis, Chapel Hill, N.C. (US); and Clark Debs Jeffries, Durham, N.C. (US) | ||
| Assigned to International Business Machines Corporation, Armonk, N.Y. (US) | ||
| Filed on Apr. 28, 2003, as Appl. No. 10/425,097. | ||
| Prior Publication US 2004/0213275 A1, Oct. 28, 2004 | ||
| Int. Cl. H04L 12/28 (2006.01) | ||
| U.S. Cl. 370—351 [370/389; 370/395.54; 370/411] | 7 Claims |
| 1. A method of processing parameter ranges for each parameter field in a packet classification rule, said method comprising:
(a) associating at least one rule with at least one dimension, said dimension being a parameter in a network packet, said
at least one rule being an instruction to a router for processing said network packet;
(b) sorting said at least one rule according to a dimension associated with each set at least one rule;
(c) grouping said at least one rule with a second at least one rule into a cluster of rules with overlapping ranges, overlap
of said ranges being determined by said at least one dimension;
(d) upon determining that said at least one rule overlaps said second at least one rule, expanding said cluster of overlapping
rules into multiple unique segments that identify unique range intersections;
(e) expanding the number of said multiple unique segments such that each rule has a number of segments that is a power of
two;
(f) offsetting each said cluster to an optimum alignment position;
(g) converting the numbering of said range segments from binary to Gray code to create Gray coded range segments;
(i) identifying a unique rule corresponding to a group of said Gray coded range segments; and
(j) utilizing the unique rule to define and instruct how a particular packet is to be routed.
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