Distributed network flow optimization algorithm with tie-set control based on coloring for SDN

This paper proposes a distributed algorithm that aims for congestion control in Software Defined Networking with distributed controllers by exploiting loop structures in a network and coloring. Our algorithm dissects a network into loop units called tie-sets and updates flows on edges by enclosed calculation in each controller, which is in charge of one of loop units. Additionally, the deployment of coloring in a tie-set meta-graph enables the distributed algorithm to avoid update conflicts in shared edges with less communications among controllers.