Software switches are increasingly used in Network Function Virtualization (NFV) to route traffic between Virtualized Network Functions (VNFs) and physical Network Interface Cards (NICs). However, our understanding of alternative switch designs remains deficient in the absence of a comprehensive comparative performance analysis. This absence may be explained both by the enormous effort required to install and configure the large spectrum of solutions and by the difficulty in defining an effective methodology that guarantees a fair comparison. In this paper, we propose a methodology and compare the performance of seven state-of-the-art software switches. We first explore their respective design spaces and then compare their throughput and latency performance under four representative test scenarios. Each scenario corresponds to a specific case of NFV traffic routing between NICs and/or VNFs. Our experimental results show that no single software switch prevails in all scenarios. It is therefore important to choose the one that is best adapted to a given use-case. The presented results and analysis bring a better understanding of design tradeoffs and identify potential bottlenecks that limit the performance of software switches for NFV.

For more information, please refer to our GitHub repo: https://github.com/ztz1989/software-switches