A TCP-friendly multicast congestion control scheme based on active network

Using multicast rather than sending data to each receiver individLially(referred to as unicast) has the potential of saving on sender and network resources, and reducing the time to completion by overlapping transmission to multiple receivers. The differences between multicast and unicast, however, bring great challenges to congestion control for large-scale multicast applications. Effective multicast congestion control mechanism is urgently needed with the deployment of multimedia multicast applications in Internet. In this paper, a novel multicast congestion control scheme is proposed through introducing active network technology, hierarchical congestion detection, report and adaptive multi-rate control based on TCP flux model. Simulations and results show that the proposed scheme responds more quickly to congestion anywhere in the multicast tree and is more stable and TCP-friendly, and maximizes the utilization of network resource due to the fact that it effectively avoids and releases congestion within limited scope of network.