Survival backup strategy for controller placement problem in Software Defined Networking

The core concept of Software Defined Networking (SDN) is to abstract the control layer from the data layer. SDN architectures can provide programmatic interfaces in communication networks that significantly simplify network management and improve utilization efficiency. Distributed multiple controller SDN environments have become the preferred solution towards better scalability of SDNs. However, there are some inevitable problems for such networks, such as network failure, especially due to the failure of controllers themselves. To further improve network performance, reliability, and survivability, one solution is to deploy backup controllers in the network to satisfy quality of service requirements. In this paper, we aim to enhance the controller placement approach by designing a reliable and survivable controller placement framework. This framework consists of two levels. The first level is to determine the number and placement of the primary controllers using the node degree, which relies on selecting the nodes with the highest degree and then generating multiple domains exploiting the Independent Dominating Set (IDS) technique to ensure efficient distribution of controllers with lowest response times. The second level aims to provide some protection for the first level through the efficient deployment of backup controllers. The approach designed at this level is called the survivable backup controller placement approach. We evaluate this framework using real topologies; the obtained results show the significant impact of integrating both levels in improving the performance of SDNs without introducing unacceptable delay times.