In Software Defined Network, the controller is so vulnerable to flooding attack. By injecting spoofed request packets continuously, attackers make a burdensome process to the controller, cause bandwidth occupation in the controller-switch channel, and overload the flow table in switch.
The final target of attackers is to downgrade or even shutdown the stability and quality of service of the network. In this paper, we introduce a feasible method to protect the network against Distributed Denial of Service attacks more effectively.