Utilising SDN to Counter BGP Convergence Delays

Software Defined Networking (SDN) is a new paradigm for the control and management of computer networks and it is now a focus for research and industrial development. SDN revolutionizes network operation, design, and management through centralized control, abstractions, flexibility and programmability. In multi-domain SDN, domains are connected using the Border Gateway Protocol (BGP) to exchange routing and path information among the domains or different autonomous systems. BGP is a long-established protocol that has remained fairly static over time. BGP suffers from a high convergence time when updates are made, and this is detrimental to the flexible operation of modern IP networks. In this paper, we investigate how the SDN paradigm could be applied to improve multi-domain SDN traffic control and management mechanism. Research into a new multi-state BGP engine is introduced that reduces the high BGP convergence time in multi-domain SDN. Improvements to BGP operation that contribute to its integration in future SDN-based flexible and programmatic networking is an important outcome.