The communication network overlaying the power grid is required to be resilient to link failures among network devices. The Software Defined Networking (SDN) architecture provides a fast-failover mechanism for provisioning networks that are seamlessly resilient. However, in order to guarantee that an SDN meets such resiliency requirements, its control-plane state needs to analyzed and validated against desired resiliency properties. In this paper, we present a framework to exhaustively analyze a snapshot of its control-plane state to compute packet flows between any pair of ports. We also present algorithms and data structures so that the changes caused by link failure/restoration to these packet flows can be computed incrementally. Our experimental results indicate that performing exhaustive analysis from scratch can take up to nine times longer than our proposed incremental computation algorithm.
['Rakesh Kumar', 'David M. Nicol']
Validating resiliency in Software Defined Networks for smart grids