Control Path Management Framework for Enhancing Software-Defined Network (SDN) Reliability

Software-defined networking (SDN) is a softwarization technology of networks that can optimize processes and operation costs and bring new values to infrastructures. The issue of reliability, however, becomes more complex in SDN due to new and multi-lateral network domains, and poses many critical challenges on the existing network reliability mechanisms in order to achieve the same reliability services. In this paper, we first identify and illustrate reliability challenges in a control path network that lies between a control plane network and a data plane network to connect them through either an in-band SDN or an out-of-band traditional network. We then observe a number of distinctive control path reliability problems. Accordingly, we propose and develop a control path management framework to enhance SDN reliability addressing the observed issues. It includes several control path reliability algorithms that enhance performance, network protocols that simplify management of control path reliability, as well as a novel control message classification and prioritization system that serves as a fundamental approach to improve scalability and then reliability for SDN. Recognizing the control path as a network and understanding its potential and practical reliability problems enable us to provide effective solutions that prior approaches fall short of. We validate our proposed management framework through extensive experiments through a real network system as well as numerical analyses.