Controller placement and flow based dynamic management problem towards SDN

The SDN architecture decouples the control plane and data plane, and multiple controllers are adopted to solve the scalability and reliability problem in SDN. However, most of the researches are focused on the control architecture and ignore the controller placement problem. Moreover, the mapping between the switches and controllers are static in current proposals, which will lead to the load unbalance of controllers under dynamic flow variations. In this paper, we define a new controller placement metric considering the node weight for a single domain at first, and then propose a dynamic switch migration algorithm to adapt to the flow dynamics and realize controller load balance in multiple SDN domains. Finally, a simple simulation platform is built to verify the proposed scheme.