Software-defined networks provide a new way to create services and to offer network resources to applications. Using the Software Defined Networking (SDN) concept, network development basically becomes a software development process. In addition to their many benefits though, they introduce a new layer that can contain software bugs and errors that were not of concern in traditional networking. To locate these problems, conventional network debugging tools and methods are not always enough - software debugging should be applied in close conjunction with network debugging tools.
Since SDN is quite a young concept, not many tools exist that can provide these functions in an integrated way. In this thesis I give a review of existing tools and then based on the observations made, I present a prototype OpenFlow troubleshooting tool, EPOXIDE. Later on, the details of the implementation of the defined specification are given and I present possible use cases where the prototype provides extra functionality compared to existing tools.