Advanced Controller Resiliency in Software-Defined Networking Enabled Critical Infrastructure Communications

In International Conference on ICT Convergence, IEEE, Jeju-si, Republic of Korea, October 2017.

Abstract:

Critical Infrastructures such as transportation or energy systems are central to the existence of modern societies. Due to the expected level of performance and developments like the shift towards renewable, fluctuating energy generation in Smart Grids, advanced monitoring and control systems are required for stable operation. This in turn increases the  dependence on robust communication technology. However, due to the distributed nature of Critical Infrastructures, dedicated communication networks entail high costs. Hence a convergence of public and purpose built networks is pursued, so mission critical applications can be handled by a shared infrastructure. Software-Defined Networking facilitates this by separating network control from physical packet forwarding and centralizing it in a controller, which also creates a single point of failure. Although approaches capable of mitigating this threat to system robustness exist, the specific requirements of e.g. Smart Grids are not sufficiently addressed. Therefore a novel broker-based approach, allowing multiple Software-Defined Networking controllers to work in concert, is presented. The broker determines the correctness of network control decisions via majority votes. This novel concept for control plane fault tolerance, specifically designed to fulfil the challenging demands of Smart Grids, is detailed and contrasted with currently employed solutions. Also, resiliency against failures as well as malicious attacks is achieved, enabling reliable and highly available Critical Infrastructure communications.