An Experimental Evaluation of Flow Setup Latency in Distributed Software Defined Networks

Abstract

Next generation application domains such as Virtual Reality (VR), Augmented Reality (AR) together with the Tactile Internet paradigm impose ultra-low latency requirements on the networks (1 to 5 ms end-to-end latency). Towards this objective, networks are undergoing a tremendous transformation from the current packet switching models to Software Defined Networking (SDN) architectures, which provide programmability to configure the network. In its simplest variant, one single centralized controller orchestrates the whole SDN infrastructure. However, the fully centralized architecture (one single controller) can become a performance bottleneck, especially in terms of response throughput and flow setup latency. Furthermore, it suffers from massive scalability issues. In this direction, a number of more sophisticated SDN architectures are currently under research. While their theoretical advantages have been thoroughly discussed in the state-of-the-art, a comparative experimental analysis of these architectures is still missing. This study aims at providing such experimental performance comparison. Herein, we put to test a set of SDN architectures ranging from a fully centralized to a completely distributed control plane, comparing them in terms of flow setup latency. Overall results show that completely distributed architectures provide significantly better performance with almost 31% gain in terms of average flow setup latency over the centralized case.