Comparing OpenFlow Controller Paradigms Scalability: Reactive and Proactive

The OpenFlow architecture is a proposal from the Clean Slate initiative to define a new Internet architecture where the network devices are simple, and the control and management plane is performed by a centralized controller. The simplicity and centralization architecture makes it reliable and inexpensive, but the centralization causes problems concerning controller scalability. An OpenFlow controller has two operations paradigm: reactive and proactive. This paper proposes a methodology to evaluate OpenFlow controller performance. The performances of both paradigms were analyzed in different known controllers. The performance evaluation was done in a real environment and emulation. It was tested distinct OpenFlow controller and using a different amount of OpenFlow devices. Finally, we will present some conclusions about the controller scalability.