OC-3072 packet classification using BDDs and pipelined SRAMs

We present a solution to the problem of quickly classifying packets. Our approach is based on techniques from logic synthesis. Specifically, we express the classification rules as Boolean logic equations, build binary decision diagrams for these equations, and then map the BDDs to a logic network consisting of a pipeline of static RAM banks. We illustrate our approach by applying it to the longest prefix matching for IP forwarding, and present evidence that our scheme can perform a billion matches per second on a CAIDA backbone forwarding table containing 60,000 prefixes. We show how our approach generalizes to classifying packets on multiple fields.