Software Defined Networking (SDN), is an archetype that decouples the management plane and information plane. Data plane is employed to only forward the information and management plane is used to make a decision however information ought to be forwarded. Open networking Foundation (ONF) may be a cluster that's employed in the development of SDN. For interfacing of management plane and data plane in SDN needs some protocol. One such protocol is Open Flow. The primary normal interface designed for SDN is Open Flow. It provides superior, dominant granular traffic across multiple vendor's network devices. As the network infrastructure of a company grows, it's very troublesome to manage and such networks from a centralized system like portable computer through programs. As an attempt during this paper we have a tendency to adopt the SDN technology to manage the networks programmatically. In this paper we have a tendency to address the problems for providing security to the network from DDoS mitigation. In this paper for DDoS mitigation we tend to square measure distribution at threshold worth in order that the SDN controller resists the DDoS attack programmatically. © 2018 IEEE.