QROUTE: an QoS-guaranteed multicast routing

In this paper, we propose QROUTE, an integrated framework for QoS-guaranteed multicast routing, in which a feasible multicast tree meeting multiple QoS constraints can be constructed in a distributed fashion using local states at routers. Compared with existing QoS-based multicast routing protocols, QROUTE is much simpler to design and implement; and its simplicity and feasibility is demonstrated through the construction of a prototype router testbed. In addition, it is more effective as it avoids flooding the network blindly, while searching all the available feasible paths in parallel so as to ensure a better chance of successful routing and a more efficient use of network resources. We also evaluate the performance of QROUTE by comparing it with other related protocols through simulations, and find that QROUTE has lower blocking probability, lower routing overhead, lower connection set-up latency, and the resulting multicast trees of QROUTE also generally require fewer links than those of the related protocols. In addition it is fairly scalable with the network sizes.