The Scalable Architecture Design For SDN Control Plane

Software Define Network(SDN)is the newest tendency of networking.The inde-pendent control plane and data plane ensure that the network behavior is under our control though coding on controller.SDN is more swift and intelligent than traditional network.For the reason of central controller,the network capacity and delay affect network extension.In normal conditions,multi-controller can be utilized to relieve this issue.In this paper,we pay our attention to the design of multi-controller architecture as a whole control plane in Software Define Network.At first,we review existing multi-controller architectures and analyze the advantages/disadvantages of these designs.Then we propose a new multi-controller architecture to achieve a better scalability via 1)hierarchical network architecture,2)abstract network view,3)in-band control channel.We assign different network roles according to different topology and then establish the in-band control channels among them.We design a topology discovery mechanism to build the basic network view by gathering,computing,synchronizing.The upper layer's network view is recursive to construct.After establishing the network view,we also design a routing algorithm for transmission.Our design pays most attention to network extension without modifying the hardware architecture and network protocols.We apply our design on simulation whose result reveals that our design achieves less overhead and faster processing rate when the the network extends to certain scale.