07953922 is referenced by 25 patents and cites 424 patents.

The number of content addressable memory (CAM) lookups is reduced from two to one. Each side (left and right sides) of a CAM is programmed with network addresses, such as IP addresses, based on certain bits of the network addresses. These bits of the network addresses (which represent packet routes) are examined and used to determine whether the particular network address is to be placed on the left or right sides of the CAM. The grouping of certain network addresses either on the left or right sides of the CAM can be performed by examining an individual bit of each network address, by performing an exclusive OR (XOR) operation on a plurality of bits of each network address, and/or by searching for bit patterns of the network address in a decision table. Network addresses that cannot be readily assigned to a particular side of the CAM using these grouping techniques are programmed into both sides of the CAM. During packet routing, techniques similar to the grouping techniques that populated the CAM are used to determine which of the two sides of the CAM is to be searched.

Title
Double density content addressable memory (CAM) lookup scheme
Application Number
12/639749
Publication Number
7953922 (B2)
Application Date
December 16, 2009
Publication Date
May 31, 2011
Inventor
Ram Dular Singh
San Jose
CA, US
Agent
Kilpatrick Townsend & Stockton
Assignee
Foundry Networks
CA, US
IPC
G06F 12/00
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