Studying Multi-rate Multicast Congestion Control with Explicit Router Feedback

Congestion control with the positive use of explicit notification that indicates internal network conditions is a promising way to address the performance issues of congestion control in high-speed networks. We previously proposed SIRENS, a scalable, robust, and flexible fine-grained explicit notification framework where each router captures a snapshot of the various kinds of downstream link status along the IP-level path from a sender to a receiver and notifies a receiver of the status. A receiver can find out the overall path status by assembling all the cumulative notifications that indicate the status in the single hop, and a sender can share the path status using feedback from the receiver. Such per-hop information is needed by endhosts to flexibly design novel congestion control mechanisms or to significantly enhance the performance of traditional forms of congestion control in specific situations. In this paper, as a typical application of SIRENS, we study receiver-driven congestion control for multi-rate multicast communications. We address the traditional issues of TCPfriendliness and low responsiveness using SIRENS. We evaluate the proposed multi-rate multicast congestion control mechanism using simulations, and show the implementation status.