Fast lookup for dynamic packet filtering in FPGA

Rapidly growing speed and complexity of computer networks impose new requirements on fast lookup structures which are utilized in many networking applications (SDN, firewalls, NATs, etc.). We propose a novel lookup concept based on the well-known cuckoo hashing, which can achieve good memory utilization, supplemented by a binary search tree for offloading the colliding keys and supporting LPM lookup. We also propose a hardware architecture implementing this lookup concept in the FPGA. Our solution is suitable for lookup of the variable-length keys in 100+ Gbps networks. Memory utilization of the proposed concept is thoroughly evaluated and it is shown that the concept is scalable to external memory components.