Multicast feedback suppression using representatives

For a reliable, feedback dependent multicast transport protocol to scale, it must avoid the feedback implosion problem, particularly if the protocol targets arbitrarily large multicast groups communicating over lossy networks. Most existing suppression based feedback control mechanisms address the implosion problem using timers based on round-trip time (RTT) estimates between each receiver and the source. The algorithm presented has three major benefits: it does not need to compute the RTT from all receivers to the source, does not require knowledge of group membership, and provides prompt feedback. A small set of representative receivers and probabilistic suppression are used to limit feedback. We believe that this approach will perform well in real networks. Simulations show that for various multicast group sizes, a few representatives can keep the amount of feedback low while not degrading feedback timeliness.