FastUp: Fast TCAM Update for SDN Switches in Datacenter Networks

TCAM is widely used for flow table lookup in Software -Defined Networking (SDN) switches for datacenter and enterprise networks. While its lookup throughput is unparalleled, TCAM updating, particularly for new rule insertions, can impair the overall system performance. A rule insertion entails two steps: I) Computing the rule moving operations; and 2) Interrupting the TCAM lookups to apply the operations. In previous work, the performance gain on one step is always at the expense of the performance loss on the other. However, update throughput and latency depend on both. In this paper, we present a faster and more balanced TCAM update scheme, which not only achieves the shortest interrupt tune so far but also significantly reduces the computation time. By using a novel sequential stack, FastUp reduces the time and space complexity of the stateof-the-art schemes from 0(702) and 0(70 to 0(nc log 17) and 0(h), respectively, where h<More