Proxy-based Optimization of Topology Discovery in Software Defined Networks
Joakim Flathagen, Ole Ingar Bentstuen · 2019
Software Defined Networking (SDN) can provide programmability, increase flexibility and simplify management of communication networks. A central concept of SDN is the separation of the control plane and the data plane. A second salient feature of SDN is that the network intelligence is concentrated to a central controller. As this controller must have an updated view of the network topology, topology discovery is an important component of an SDN network. The discovery process is, however, costly in terms of control message overhead. In this paper, we propose a proxy based discovery approach that can reduce the overhead substantially compared to the state-of-the-art discovery method. By using a proxy, the efficiency gain can be achieved without altering the switch configurations, or the OpenFlow protocol. We have analyzed the proposed method using a test bed and compared it both to the current state-of-the art method and an alternative optimization method found in literature. Despite the reduction in control overhead by our method, the ability to discover the network topology was not reduced.