Software-Defined Networking (SDN) and 5G Network: The Role of Controller Placement for Scalable Control Plane

The evolution of wireless networks from the first to fourth generation has made smart devices and technologies a significant part of our daily activities. The 5G network is a ground-breaking technology that proposes to transform the way individuals use the internet, via the creation of enabling atmosphere. 5G promises faster and superior quality with better security guarantee in comparison to preceding technologies. The software defined networking (SDN) on the other hand is an enabling technology needed to actualise the huge promises of 5G network. With extensive network in 5G, a centralised controller approach in SDN has limitations related to the performance and scalability. Several studies have advocated the use and placement of multiple controllers to improve scalability in SDN. Controller placement problem (CPP) becomes more of a challenge, especially when network nodes/links and controllers have some constraint metrics such as latency, network load and distance. This paper proposes a multi-criteria clustering method that places the controllers based on a predefined constraint metrics between the controllers and the switches while minimising the overall latency. The results showed the proposed technique improved nodes distribution than existing solutions for a dense network anticipated in 5G scenario.