Load-dependent flow splitting for traffic engineering in resilient OpenFlow networks

In this paper we propose and investigate load-dependent load balancing for resilient OpenFlow networks. The objective is to spare extra capacity for the primary path of a traffic aggregate (flow) by accommodating excess traffic on its backup path. The contribution of the paper is manyfold. We explain existing OpenFlow features for traffic monitoring and dynamic flow splitting, combine them to implement load-dependent balancing of a flow´s traffic on its primary and backup paths, and propose three different load-dependent flow splitting (LDFS) policies. We develop a performance evaluation method to quantify the capacity for load-balancing and protection switching methods such that expected traffic can be accommodated for envisioned overload and failure scenarios. Finally, we assess the usefulness of LDFS by comparison with traffic-agnostic single- or multipath forwarding methods.