ABSTRACT

Software-defined networking (SDN), which decouples the control plane from data plane and provides programmability to design the network, has been considered as a viable paradigm shift to ease the management of conventional networks. Studies have identified that the placement of controllers heavily impacts network performance in SDN. Many studies proposed methods regarding controller’s placement in the network to improve the performance metrics such as propagation latency, distribution of load, failure resilience, and reliability of network. However, network operators' main concern is always Quality of Service (QoS) when placing SDN controllers. Because SDN controllers are responsible for providing services to the switches, controller response time is a critical QoS criterion for network operators. In this study two different approaches of controller placement were thoroughly examined and combined to offer a solution that minimizes the propagation delay among nodes and maximizes the QoS of the network by maintaining better load balancing.

Keywords: - Software Defined Networks, Controller Placement, QoS, Load-balance, Propagation delay