Core-based Routing with QoS Support for Distributed Interactive Multimedia Applications

Distributed interactive multimedia applications such as video conferencing and virtual collaboration applications typically involve frequent interactions among multiple distributed parties. These applications require an efficient networking support such as core-based routing with Quality of Service (QoS) support. Typical core-based routing selects one router as a core for a multicast group and builds a single multicast tree rooted at the core to deliver data to the entire multicast group. Routing with a single core, however, may not satisfy QoS requirements of many distributed group members. Hence, we introduce in this paper new QoS core-based routing called Core Set Routing that utilizes the smallest set of cores that can satisfy QoS requirements of as many group members as possible. As part of this paradigm, we present our new distributed core selection protocol and multicast tree construction protocol that ensures loop-free routing and offers several desirable properties. We discuss a novel QoS constrained path search protocol and a protocol for handling member and sender dynamics. Last, we present the performance of our core selection and multicast tree construction protocols. The simulation results demonstrate that our core set routing can satisfy significantly more group members compared with a recent QoS based routing using a single core. Besides, our tree construction protocol does not impose much overhead on the networks.