Statistical multiplexing and mix-dependent alternative routing in multiservice VP networks

We consider problems in traffic integration and routing for virtual path (VP)-based multiservice networks. The objective is to exploit statistical multiplexing among various traffic types in order to improve system utilization. Difficulties arise due to statistical multiplexing since a connection's bandwidth requirement depends on the characteristics of the interfering traffic. We first consider whether segregating heterogeneous traffic with different quality of service (QoS) requirements on separate VPs is desirable. Next we consider routing heterogeneous permanent connections given a predefined traffic type mix onto multiple VPs between a source destination pair. We show that it is not necessarily advantageous to have each VP carry every traffic type. In fact, perhaps surprisingly, an optimum solution to this problem suggests that only a small number of traffic types, or even homogeneous traffic, need be present on each VP. Based on this observation, we propose a simple alternative routing algorithm with routing sequences depending on the traffic mix.