Queueing analysis of software defined network with realistic OpenFlow–based switch model

Abstract

Software Defined Networking (SDN) is the latest networking paradigm that espouses the separation of the control plane from the data plane for increased flexibility in the routing of flows through the network. Closely associated with SDN is OpenFlow, the most widely used protocol governing the information exchange between the data plane (switching devices) and the control plane (controller). The ease of implementing and testing new schemes in SDN has prompted many researchers to adopt the experimental and prototyping approach to validate their ideas. While the experimentation approach in validation has merits, analytical modelling provides valuable insights by making explicit the dependence of SDN performance on chosen parameters of interest. However, there is no exact queueing analysis of SDN with OpenFlow switches. In this paper, (i) we propose a queueing model of an OpenFlow–based SDN that takes into account classful treatment of packets arriving at a switch and (ii) provide an exact analysis of the proposed queueing model. In tandem, these two aspects have not been accurately modelled (if at all) by the handful of research done in this area. The proposed queueing model is validated by simulation and measurements on a test network and the prediction errors for simulation and measurements are lower than 2% and 10.5% respectively.