Software defined networking has become an extremely popular field of research recently, opening new possibilities in the world of networking. Using the OpenFlow protocol gives an insight into what possibilities exist to tailor and deploy complex networks to one’s own vision. There are numerous open source tools compatible with the OpenFlow protocol, with which the behavior of different network components can be modified by customizing their code.
The purpose of this thesis is to show how the protocol’s standard messages can be extended in order to discover the control channel of the protocol, thereby gaining information about middle boxes which are otherwise hidden. After introducing the protocol and its message layer at a low level, I will investigate the possibility of extending it throughout the different versions. I will outline the application that was used to create the controller, then the FlowVisor that was used for modeling the middle box.
Finally I will explore the different options, then implement the chosen design and conclude with my results.