SRSO: A Scalable Routing Scheme for Large-Scale Open Flow Networks

Abstract

Open Flow has emerged as a new networking architecture that separates the control and data planes. A centralized controller which maintains a global network view completes all the functions in control plane. When a new flow arrives, the controller computes global optimal routing path for this flow and adds corresponding flow entries into all switches along the path. Obviously, the amount of messages exchanged between controller and switches grows with the size of network. As a result, the poor scalability of traditional Open Flow routing scheme becomes more and more obvious. To alleviate this problem, we propose SRSO, a scalable routing scheme for large-scale Open Flow networks. When routing a flow, SRSO only adds flow entries into a part of switches (not all switches) along the path. Comparing with traditional Open Flow routing scheme, SRSO achieves better performance of scalability through decreasing the amount of exchanged messages destined to the control plane. Furthermore, we develop components on POX controller to implement SRSO and test its feasibility in real environment. At the end of this paper, the simulation results show that our proposed SRSO can obtain better scalability performance in large-scale Open Flow networks.