A High-Performance and Energy-Efficient TCAM Design for IP-Address Lookup

In this brief, we propose a two-level don't-care gating (DCG) scheme that aims to reduce the ternary content-addressable memory (TCAM) power dissipated in the search-line switching activity. By exploiting the vertically continuous ldquodon't-carerdquo feature, the two-level DCG scheme can largely reduce the average search-line power consumption during a switch pattern. In addition, we also use the search enable technique to eliminate the unnecessary search-line switching activity in the quiet pattern. By reducing both the search-line switching activity and average switching power, the proposed design can minimize the TCAM search-line power consumption. For a 128 times 32 TCAM, the best configuration we examined shows that when the first-level and second-level gating granularities are 16 and 8, respectively, with a 9% search performance improvement, the two-level DCG scheme can achieve 70% search-line energy reduction.