A NEW DISTRIBUTED QOS ROUTING ALGORITHM FOR SUPPORTING REAL-TIME COMMUNICATION IN HIGH-SPEED NETWORKS

Distributed multimedia applications are often sensitive to the Quality of Service (QoS) provided by the communication network. They usually require guaranteed QoS service, so that real-time communication is pos sible. However, searching a route with multiple QoS constraints is kno wn to be a NP-complete problem. In this paper, we propose a new simple and efficient distributed QoS routing algorithm, called ''DQoSR,'' fo r supporting real-time communication in high-speed networks. It search es a route that could guarantee bandwidth, delay, and delay jitter req uirements. Routing decision is based only on the modified cost, hop an d delay vectors stored in the routing table at each node and its direc tly connected neighbors. Moreover, DQoSR is proved to construct loop-f ree routes. Its worst case message complexity is O(\V\(2)), where \V\ is the number of nodes in the network. Thus DQoSR is fast and scales w ell to large networks. Finally, extensive simulations show that averag e rate of establishing successful connection of DQoSR is very near to optimum (the difference is less than 0.4%).