Automated source code extension for debugging of OpenFlow based networks

Software-Defined Networks using OpenFlow have to provide a reliable way to to detect network faults in operational environments. Since the functionality of such networks is mainly based on the installed software, tools are required in order to determine software bugs. Moreover, network debugging might be necessary in order to detect faults that occurred on the network devices. To determine such activities, existing controller programs must be extended with the relevant functionality. In this paper we propose a framework that can modify controller programs transparently by using graph transformation, making possible online fault management through logging of network parameters in a NoSQL database. Latter acts as a storage system for flow entries and respective parameters, that can be leveraged to detect network anomalies or to perform forensic analysis.