Testing comparison faults of ternary CAMs based on comparison faults of binary CAMs

ABSTRACT

With the increasing demand for high-performance networking application, network components such as network interfaces and routers are built in dedicated hardware modulars. Content addressable memories (CAMs) play an important role in the network components. Testing CAMs is very complicated due to their special structure. This paper presents an efficient March-like test algorithm for detecting the comparison faults of ternary CAMs based on the comparison fault models of binary CAMs. The test algorithm requires 5N Write operations, 2N Erase operations, and (3N + 2B) Compare operations for an N x B-bit TCAM.

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