Preventive model-based verification and repairing for SDN requests
Résumé
Software Defined Networking (SDN) devices (e.g., switches) route traffic according to the configured flow rules, and thus a set of virtual paths gets implemented in the data plane. We propose a novel preventive approach for verifying that no misconfigurations (e.g., infinite loops), can occur given the requested set of paths. Such verification is essential since when configuring a set of data paths, other not requested and undesired paths (including loops) may be unintentionally configured. We show that for some cases the requested set of paths cannot be implemented without adding such undesired behavior, i.e., only a superset of the requested set can be implemented. We present a verification technique for detecting such issues of potential misconfigurations and estimate the complexity of the proposed method. Finally, we propose a technique for debugging and repairing a set of paths in such a way that the corrected set does not induce undesired paths into the data plane, if the latter is possible.