On the effect of flow table size and controller capacity on SDN network throughput

摘要

Software Defined Network (SDN) is an architectural trend in networking towards the use of the centralized controller to get better performance. However, due to limited resources (especially limited flow table size and controller processing capacity), it may result in low-throughput and long-delay for a set of bursty flows. In this paper, we first combine the flow table size constraint and the controller processing capacity constraint to define the Throughput Maximization with Limited Resources (TMLR) problem. Then we prove TMLR is NP-Hard and design an approximation algorithm to solve the TMLR problem. The approximation factor of the proposed algorithm is also analyzed. The simulation results on the SDN platform (Mininet [1]) show that our algorithm can improve the network throughput about 39% on average compared with the existing algorithms.