MULTI+: a robust and topology-aware peer-to-peer multicast service

TOPLUS is a lookup service for structured peer-to-peer networks that is based on the hierarchical grouping of peers according to network IP prefixes. In this paper, we present MULTI+, an application-level Multicast protocol for content distribution over a TOPLUS-based peer-to-peer (P2P) network. We use the characteristics of TOPLUS to design an overlay Multicast protocol that allows every peer to connect to an available peer that is close. MULTI+ trees also reduce the amount of redundant flows leaving and entering each network, making efficient usage of the bandwidth. We also study the resiliency of MULTI+ Multicast trees when massive failure or disconnection of peers occur. While the tree reconstruction introduces additional hops, the end-to-end latency increases very little. At the end we compare the trees constructed by MULTI+ with the trees constructed by Scribe, a well-known application-level Multicast system.