Delay-Differentiated Routing in Meshed Backbone Networks

Today’s network applications require strict quality of service (QoS) guarantees, e. g., in terms of availability or delay. Due to shortest path routing in backbone networks, the point-to-point delay is usually very low. However, this is not only true for the services with strict delay requirements but also for all others. Since there is no customer-perceivable delay difference, it is difficult for the network operator to justify differences in pricing between low-delay and other services. We propose a routing and network reconfiguration approach for packet-optical networks that enforces delay differentiation by routing on non-shortest paths. We present an integer linear program formulation and study the effects of our approach by simulation in two backbone topologies. We show that a considerable number of services can be routed with delay differentiation if the use of additional spectral resources is allowed.