A dormant multi-controller model for software defined networking

In order to improve the scalability and reliability of Software Defined Networking (SDN), many studies use multiple controllers to constitute logically centralized control plane to provide load balancing and fail over. In this paper, we develop a flexible dormant multi-controller model based on the centralized multi-controller architecture. The dormant multi-controller model allows part of controllers to enter the dormant state under light traffic condition for saving system cost. Meanwhile, through queueing analysis, various performance measures of the system can be obtained. Moreover, we analyze the real traffic of China Education Network and use the results as the parameters of computer simulation and verify the effects of parameters on the system characteristics. Finally, a total expected cost function is established, and genetic algorithm is employed to find the optimal values of various parameters to minimize system cost for the deployment decision making.