An associative RAM-based CAM and its application to broadband communications systems.

The content addressable memory (CAM) is a memory device that executes fast recognition and validation of binary patterns of a limited set, as opposed to the random access memory (RAM) that executes slow recognition of a large set of patterns. Here, we present a logic circuit which, combined with existing RAM, constructs an associative RAM-based content addressable memory (AR-CAM) that executes fast pattern recognition of very large pattern sets. In addition, we describe the applicability of the AR-CAM to broadband communications systems. Broadband communications systems with an aggregate bandwidth of tens or hundreds of Gbps require real-time recognition and translation of large pattern sets. Although CAM are a good candidate for such applications, nevertheless we demonstrate that AR-CAM can better and inexpensively accomplish this task.