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Lightweight reliable overlay multicasting in large-scale P2P networks

Because of the complexity, cost and limited deployment of multicast capability at the network layer, application layer multicasting between end hosts has become an attractive option for distributing content among a large number of users based on a peer-to-peer architecture. In contrast to network layer multicasting where the tree nodes are fairly static, multicasting in P2P networks has unique characteristics: the large number of network nodes participating in the multicast operation, and the fact that network nodes may drop out, move or join at a significantly higher frequency than in network layer multicasting. These features pose certain challenges for network service designers, in particular regarding how to guarantee continuous multicast service in face of parent node departure or link/node failures, an issue that is referred as service restorability. In this paper we examine a hybrid architecture that contains both a static overlay backbone (i.e. owned by service provider) and dynamic nodes (mostly end hosts). A design for service survivability is examined, and a flexible lightweight approach is proposed that achieves survivability in large-scale networks using minimal resources at individual node.