Explaining safety failures in NetKAT

This work introduces a concept of explanations with respect to the violation safe behaviours within software defined networks (SDNs) expressible in NetKAT. The latter is network programming language based on well-studied mathematical structure, namely, Kleene Algebra Tests (KAT). Amongst others, foundation NetKAT gave rise sound and complete equational theory. In our setting, behaviour characterised by policy, or program, which does not enable forwarding packets from an ingress i undesirable egress e. We show how for safety violations can be derived fashion, according modification existing axiomatisation. propose approach Maude system actually computing undesired witnessing e as above. SDN-SafeCheck tool theories satisfying important properties such Church-Rosser termination. automatically identifies all leading e, covering paths up user specified size.