Solving MP-TCP's Shared Bottlenecks Using a SDN with OpenDayLight as the Controller

MP-TCP (MultiPath-Transmission Control Protocol) was designed to use multiple interfaces in hosts; it uses several subflows (a set of regular TCP connections) to increase the performance compared to TCP. However, when a host has only one network interface but several subflows are created, they follow the same path to their destination generating bottlenecks and MP-TCP advantages are lost. This paper presents a solution to the shared-bottleneck problem using SDN (Software Defined Networking). A plugin for OpenDayLight is developed for implementing Dijkstra's Algorithm to find paths and assign them to new subflows avoiding bottlenecks. The solution supports concurrent MP-TCP connections. Results of tests obtained using the implemented plugin in several topologies are presented.