Advanced Hashing Schemes for Packet Forwarding Using Set Associative Memory Architectures
Building a high performance IP Packet Forwarding (PF) engine remains a challenge due to increasingly stringent throughput requirements and the growing size of IP forwarding tables. The router has to match the incoming packet's IP address against all entries in the forwarding table. The matching process has to be done at increasingly higher wire speed; hence, scalability and low power consumption are critical for PF engines. Various hash table based schemes have been considered for use in PF engines. Set associative memory can be used for hardware implementations of hash tables with the property that each bucket of a hash table can be searched in a single memory cycle.