A Reliable Capacitated Controller Placement in Software Defined Networks

Software Defined Networking (SDN) is a promising area in the modem network technology giving a lot of advantages to the network operators such as programmability, high flexibility, and controllability. The control's logic is moved into a centralized remote controller. In a wide area network with multiple controllers, the number and placement of these may influence the reliability and performance of SDN. In case of controller failure, the disconnected switches must be reassigned to other working controller to maintain the network configuration and management. The propagation latency may increase due to controller failure which will lead to the increase cost of the network. In this paper, we propose a mathematical model for reliable controller placement considering it as a multi-objective problem which satisfies certain constraints. The proposed formulations are evaluated on various network topologies showing the effectiveness of the approach.