Abstract: A distributed QoS heuristic algorithm based on unicast routing by applying the concept of the cost and delay-bounded is proposed. This algorithm can generate therouting path that is subject to a sub-optimal network cost under the conditionof delay constraint, with a relatively low message complexity. And it needs no information stored in media router during the path setup. Simulations have been done to show the efficiency of the algorithm proposed.

Key words: quality of service, unicast routing, routing algorithm