Network Cost Optimization-based Capacitated Controller Deployment for SDN.

Software-defined networking (SDN) is expected to simplify network management and offer efficient and flexible supports to diverse user services. To meet the demanding transmission requirements of various SDN switches, the optimal deployment of controllers has become an important problem. In this paper, the capacitated controller deployment problem is studied for SDN where a number of candidate controllers with given constrained capacity can be deployed to enable centralized management in the control plane of SDN. Considering both transmission time and cost of the controllers, we formulate the capacitated controller deployment problem as a network cost minimization problem. To solve the optimization problem, we propose a two-stage heuristic algorithm which first tackles the controller deployment problem under the unlimited capacity constraint, and then solves the controller-capacity matching problem. Specifically, in the first stage, we study uncapacitated controller deployment problem and propose a minimum eccentricity-based controller deployment strategy to determine the number and location of controllers. In the second stage, considering the capacity constraint and cost of candidate controllers, we propose an iterative Kuhn-Munkres (K-M) algorithm to solve the controller matching problem. Simulation results verify the effectiveness of the proposed algorithm.