Patent ID: 7554978
Filing Date: 2009-06-30
Classification: H04L

Abstract:
1. A system for accessing a content-addressable memory in a pipelined packet processing system, the memory having a plurality of locations, each associated with a value of a key and a content value, comprising: a register for holding a data element having a key field, the key field having a value; and logic for deriving a value of the key responsive to 1) packet processing state data indicating state of processing of one or more packets undergoing processing by the pipelined packet processing system, and 2) the value of the key field of the data element held by the register, and presenting the derived value to the memory; wherein the memory is configured to search for a location associated with the derived value of the key presented to it by the logic, and, if such a location is found, output the content value associated with the location, and, if such a location is not found, outputting a signal indicative of a miss condition; wherein the packet processing state data comprises a sequence control table index.