Dynamic Flow Aggregation in SDNs for Application-aware Routing

The software defined network (SDN) presents a good opportunity to realize application-aware routing by offering programmability for the network. Due to limited sizes of ternary content addressable memories (TCAMs) in SDN switches, flow aggregation is needed to resolve the flow table overflow problem. We propose bit & subset weaving to relieve the problem which utilizes instruction slicing to produce an instruction-independent partition and applies the bit and subset weaving to merge flow entries in each subset of a partition. Comparing with the Fast Flow Table Aggregation (FFTA) scheme [7], the average compression ratio (the average flow aggregation time) of the proposed bit & subset weaving is better (smaller) than that of FFTA.