Dynamic management of control plane performance in software-defined networks

Abstract

The controller or the control plane is at the heart of software defined networks (SDN). As SDN migrates to wide area networks (WAN), scalability and performance are two important factors that differentiate one controller from another, and they are critical for success of SDN for end-to-end service management. We distinguish control flows from data flows, and introduce a novel dynamic control plane architecture to distribute different control flows among multiple controller instances depending on specific controller load and controller processor utilization or on the data flow service type. We propose control flow tables - a concept introduced in this paper - that are embedded in OpenFlow flow tables to distribute the control flows among various controller instances. Experimental results demonstrate the improvements in the data plane service performance as a result of the proposed control flow management procedures when the bottleneck is the controller CPU or throughput of links between the controller and switches.