A characterisation of verification tools for software defined networks

Software-defined networking (SDN) is a new paradigm to introduce intelligence in communication networks through centralised programming. SDN separates data and control plane with two main components, the programmable switches (data plane) and the central controller where network applications are executed. This highly programmable and flexible network introduces many challenges from the point of view of reliability (or robustness), and operators need to ensure the same level of confidence as in previous less flexible deployments. This paper provides a first study of the current verification tools used to analyse different properties of SDNs before deployment and/or during the exploitation of the network. Most of these tools offer some kind of automatic verification, supported by algorithms based on formal methods, but they do not differentiate between fixed and mobile/wireless networks. In the paper, we provide a number of classifications of the tools to make this selection easier for potential users, and we also identify promising research areas where more effort needs to be made.