PLS: Proactive Load Shifting for Distributed SDN Controllers

Balancing the workload among distributed SDN controllers plays a critical role for both the network performance and the control plane scalability. Therefore, various load balancing techniques were proposed for SDN to efficiently utilize the control plane's resources. However, such techniques suffer increased latency and packet loss resulting from load migration and intensive communication among the SDN controllers. The existing solutions adopt load migration based on CPU utilization, which are susceptible to inconsistent load spikes. In this paper, we formally define the problem and present an alternate approach called PLS that constitutes the cornerstone for addressing this problem. We then show through experimental results that our approach provides accurate responses to load migration event triggers.