The OpenFlow framework enables flow-level control over Ethernet switching, as well as centralized visibility of the flows in the network. OpenFlow's coupling of these features comes with costs, however: the distributed-system costs of involving the OpenFlow controller on flow setups, and the switch-implementation costs of involving the switch's control plane too often. In this paper, we analyze the overheads, and we propose DevoFlow, a modification of the OpenFlow model in which we try to gently break the coupling between centralized control and centralized visibility, in a way that maintains a useful amount of visibility without imposing unnecessary costs. Categories and Subject Descriptors C.2.1 [Computer-Communication Networks]: Network Architecture and Design General Terms Design, Performance, Measurement Keywords Network, OpenFlow, Traffic Engineering, Enterprise
Jeffrey C. Mogul, Jean Tourrilhes, Praveen Yalagan