Performance computation and implementation of distributed controllers for reliable software-defined networks

Software-defined networks (SDNs) are designed to cover the dynamic operations of network factors and the complex role of controlling components to achieve scalability and security. In SDNs, the operating process is computed through a centralized controller, and failure of the controller leads to the entire network's breakdown. Since the centralized controller's reliability is due to a single point of failure, the implementation of distributed controllers for reliable SDN networks (IDCR) has been applied to resolve this difficulty. The focus of this approach is to enhance the reliability of the SDNs with distributed controllers. In this approach, the broad network is divided into smaller subnetworks, and each network is operated through a controller to decrease the number of breakdowns. Here, reliability was computed through the route and connection reliability. Then, the controller with the highest reliability is regarded as the coordinator controller. The simulation results have proven that the IDCR approach reduces both the network delay and the failure probability. Furthermore, the approach decreases the controller overhead.