Controller Elastic Managing Strategy Based on Distributed Deployment in SDN

In order to address the problem of unreasonable network dividing and unbalanced controller deploying in software defined networking (SDN), this paper proposes a controller elastic managing strategy (CEMS) based on distributed deployment in SDN. CEMS includes two phases: subdomain planning and controller optimizing. In phase 1, the nodes are clustered according to the attraction degree and attribution degree, and we could achieve the reasonable network partitioning and the selection of controller location. In phase 2, through the weighted summation of delay, failure degree and communication overhead, the nonlinear iteration is performed for the corresponding weights, then we optimize network overheads and the number of controllers in subdomains. Simulation shows that, compared with the existing schemes, this strategy could balance the network partitioning; reduce the delay and compress the backup space of controller.