SDN Architecture Impact on Network Security

The Software Defined Networking (SDN) paradigm introduces separation of data and control planes for flow-switched networks and enables different approaches to network security than those existing in present IP networks. The centralized control plane, i.e. the SDN controller, can host new security services that profit from the global view of the network and from direct control of switches. Some security services can be deployed as external applications that communicate with the controller. Due to the fact that all unknown traffic must be transmitted for investigation to the controller, maliciously crafted traffic can lead to Denial Of Service (DoS) attack on it. In this paper we analyse features of SDN in the context of security application. Additionally we point out some aspects of SDN networks that, if changed, could improve SDN network security capabilities. Moreover, the last section of the paper presents a detailed description of security application that detects a broad kind of malicious activity using key features of SDN architecture.