Optimal Controller Placement Problem in Internet-oriented Software Defined Network

The feasibility, scalability and performance of Internet-oriented Software Defined Network (SDN) are confronted with severe challenge, so it needs multiple controllers that influence every aspect of SDN performance. An effective placement algorithm of these controllers is especially important. In this paper, we formulate the Multiobjective Optimization Controller Placement (MOCP) problem and focus on maximizing network reliability, maximizing controller load balance ability and minimizing latency between controllers and switches and then solve the optimal selection of controller placement locations, within which nodes are under control of each controller and the optimal distribution of their routing requests among these controllers. We formulate this problem into a mathematical model as the optimization objective function. In order to resolve this model, Adaptive Bacterial Foraging Optimization (ABFO) algorithm is developed on account of the computation complexity according to actual network state. The results show this proposed scheme The results show this proposed scheme has great potential to deal with above optimization objectives efficiently and effectively.