Addressing Heterogeneity and Scalability in Layered Multicast Congestion Control

In this paper, we design SIM, a protocol that integrates three distinct mechanisms – Selective participation, Intra-group transmission adjustment, and Menu adaptation – to solve the general multicast congestion control problem. We argue that only a solution that includes elements of each mechanism can scale and adapt to heterogeneity in network and receiver characteristics. In our protocol, these mechanisms operate at different time scales and distribute the responsibility of adaptation to different entities in the network. Per our knowledge, SIM is the first protocol for layered multicast that adjusts not only the subscription levels of the receivers but also the transmission rates of the layers. We show that SIM is efficient and stable in the presence of heterogeneous receivers and dynamic changes in the bottlenecks and session membership. SIM also outperforms RLM in terms of stability and efficiency.