A Novel High Performance Packet Classification Architectures

Abstract

Modern IP network systems provide differentiated services to improve quality of service. Differentiated services are implemented using packet classification. Ternary content addressable memory (TCAM) is a hardware-based packet classification, which promises better performance than the software/hybrid. All types of packet classification follow three types of matching scheme 1) Longest Prefix Match (LPM) 2) Range Match (RM) and 3) Exact Match (EM). Though TCAM Chips promises superior performance, it suffers from the following challenges like 1) It does NOT support range match 2) The last stage of TCAM chip is priority encoder, which will limit the performance of the best match classification 3) Longer Matchline Capacitance lowers the density of the chip.