Abstract. In recent years, SDN has become the network technology which the academic and industry most concerned about following cloud computing. Compared with the traditional network, SDN forwards the network control plane and data plane separation, and implements programming control centralized. At first, based on the brief introduction of SDN basic definitions and concept, this paper described the architecture and key technologies of SDN, and a survivability enhancement self-configuration technology based SDN was proposed, which was implemented by the combination of SDN, network virtualization and cloud computing, finally outlined the challenges encountered in the development process of SDN.