Network Optimization for Differentiated QoS Traffic in an SDN Environment for PoP-Data Center Traffic

A major challenge for network providers is to design a network that can cater to differentiated quality-of-service (QoS) for different traffic classes in a cost-effective manner. Traditional differentiated services ("DiffServ") is for IP networks where differentiation is done in IP packet headers through code points. However, this does not by itself land in architecting a network from a traffic engineering point of view. In an SDN environment, with more control over flows or a collection of flows, differentiated QoS traffic classes can be considered and accordingly a network can be optimized. In this work, we consider network optimization in a software-defined network (SDN) environment where differentiated QoS traffic is provided through different latency bounds. We present a mixed integer linear programming (MILP) formulation for this problem. The study shows that our approach can maintain more stringent QoS requirement by reducing the value of maximum allowable latency without a significant increment in bandwidth cost.