Research On Energy-Efficient Clustered SDN Controller Based On Elastic Control Technology

The rapid development of the socioeconomic and Internet technology requires a more scalable,trustworthy,reliable network.Traditional network can not meet those demands since it is inflexible.Under these circumstances,SDN(Software Defined Networking)become a popular paradigm in many modern networking scenarios,such as data center and cloud.Inevitably,centralized control in a single controller is likely to become the bottleneck of network performance.Clustered SDN controller has been proposed to address the problem of poor scalability.However,a key limitation in clustered SDN controller is that the mapping between controller and switch is statically configured,which may result in serious load imbalance and energy waste.In order to solve the problems mentioned above,we propose a load-adaptive energy-efficient module,and deploy this module in clustered OpenDaylight controllers.In our design,working controller pool could dynamically grow or shrink according to data plane traffic variations.When traffic fails below a certain threshold,we choose some light-weighted controllers,remove all their switches,then power off them.We keep the number of working nodes greater than two.In this way,we provide an energy-efficient clustered controllers and also guarantee high availability.