ROUTING AND ADMISSION CONTROL ALGORITHMS FOR MULTIMEDIA TRAFFIC

Interactive voice and video applications (e.g. teleconferencing) over multi-hop packet-switched networks require bounds on delay, loss and jitter. This paper compares routing algorithms and admission control methods which are intended to provide the quality of service required by such applications. The method of comparison is detailed simulation. As part of this work, we propose several novel real-time routing algorithms. The best-performing routing algorithm is a new method which takes into account the constraints imposed by the admission control algorithm. A routing algorithm similar to those used in the phone system is the worst of the dynamic algorithms; static routing is far worse than any of these. The differences between the routing algorithms are greatest when the network is highly connected, and when admission control constraints are difficult to meet. The issue of fairness is also considered in the evaluation of the routing algorithms. Three admission control algorithms were compared under varying traffic conditions and QoS requirements. The impact of traffic shaping on link utilizations was investigated. Overall, the choice of admission control method was more important than the choice of routing algorithm. This work is the first detailed evaluation of routing algorithms for voice and video traffic in multi-hop networks that provide strong end-to-end guarantees.