A Security Framework for SDN-Enabled Smart Power Grids

Emerging software defined networking (SDN) paradigm provides flexibility in controlling, managing, and dynamically reconfiguring smart grid networks. It can be seen in the literature that considerably less attention has been given to provide security in SDN-enabled smart grid networks. Most of the efforts focus on protecting smart grid networks against various forms of outsider attacks only by providing consistent access control, applying efficient and effective security policies, and managing and controlling the network through the use of a centralized SDN controller. Furthermore, centralized SDN controllers are plagued by reliability and security issues. This paper presents a framework with multiple SDN controllers and security controllers that provides a secure and robust smart grid architecture. The proposed framework deploys a local IDS in a substation to collect the measurement data periodically and to monitor the control-commands that are executed on SCADA slaves. A global IDS in control center collects the measurement data from the substations and estimates the state of the smart grid system by utilizing the theory of differential evolution. The global IDS further verifies the consequences of control-commands issued by SDN controller and SCADA master. An alarm is generated upon detection of an attacker or unsteady state of the smart grid system. The framework also deploys light-weight identity based cryptography to protect the smart grid network from outside attacks. Performance comparison and initial simulation result have been presented to show that the proposed framework is effective as compared to existing security frameworks for SDN-enabled smart grids.