A New Algorithm Based on Hellinger Distance for Mitigation of DDoS Attacks in Software Defined Networks

Software defined network (SDN) was born to make changes to existing network architectures and devices with specific function to reach an intelligent network. Recently, this networks have gained popularity in enterprise networks because of the flexibility in network service management and reduced operational cost. In this architecture, operating system and applications from the network switch are decoupled. They centralized in a virtual layer that called the controller. In the SDN, due to the centralized decision-making and resources controller limitations are exposed to all kinds of threats such as Distributed Denial of Service (DDoS) attacks. In this paper we will review SDN architecture and DDOS attacks in SDN. We proposed a novel detection and mitigation algorithm that takes advantage of unique features of the SDN architecture. In the proposed algorithm, for detecting DDOS attacks in SDN, a statistical method based on Hellinger distance and Exponential Weighted Moving Average (EWMA) technique are used. In this paper, DDOS attacks in SDN is simulated by MiniNet emulator with Pox controller. Our experiments performed in the simulator, showed the efficiency of the proposed method and its superiority compared to previous approaches.