How to Insure Reliability and Delay in Multi-controller Deployment.

In this paper, we researched the multi-controller deployment problem. Because the switch is completely dependent on the controller, if a forwarding plane failure happens, it may lead to communication interruption between the switch and its controller, the switch will become a “headless fly”, so ensuring the reliability of the communication between the switch and its controller is necessary. Because the controller and its management within the domain of the exchange of communications will be very frequent, we want to ensure reliability while making the delay between the controller and the switch become short. Therefore, our algorithm mainly considerate the following two aspects: (1) Increase the communication reliability between the switch node and the controller node. (2) Minimize the delay between the controller and the switch, that is, minimize the average delay between the controller and the switches which under its management. The concrete implementation is divided into the following steps: First, model the network, consider the stability of the forwarding plane and the delay between the switch and the controller to establish the optimization target. And then propose a two-stage algorithm. Finally, perform the simulation on the real network topology. The results of the test show that the solution is working and functional.