Fine-grained bandwidth allocation in software-defined networks

Abstract

We study the prototype for fine-grained bandwidth allocating managers (FGBAM) which allot communication bandwidth inside heterogeneous software-defined networks (SDN) based on user-defined policies. FGBAM can be beneficial in enabling Quality-of-Service (QoS) during both normal periods and disaster recovery time. FGBAM consists of two parts: the web-based front end and the back end for enforcing bandwidth allocation policies. The web-based front end facilitates network administrators in specifying bandwidth allocation policies for packet flows of interest. The back end of FGBAM enforces bandwidth allocation policies by acting as a proxy between the network devices (i.e. switches and routers) and SDN controllers. Our bandwidth manager has four desirable properties. Firstly, FGBAM supports fine-grained bandwidth allocation policies. That is, it allows allotting communication bandwidth of one port among many packet flows. Secondly, using the proxy manner, FGBAM is transparent to both SDN controllers and network devices in a software-defined network. It requires no changes in configurations of both SDN controllers and network devices. Thirdly, FGBAM can cooperate with market-leading SDN controllers of many kinds, Beacon, Floodlight, NOX, Trema, just to name a few. Last but not least, FGBAM can enable QoS in heterogeneous environment in which an SDN composes of network devices running different releases of the OpenFlow protocol. Being able to provide QoS in heterogeneous SDNs is crucial while vendors and network administrators are slowly catching up with the evolutionary of the protocol. We evaluated the performance of FGBAM in a simulated environment. The results showed that FGBAM can allocate fine-grained communication bandwidth for packet flows of interest. In addition, the results were achieved without any change applied to configurations of network devices and SDN controllers.