A server relay recovery strategy (SRRS) for reliable multicast over Internet-like topologies

For the last decade, a number of hierarchical reliable multicast schemes have been proposed in the literature due to their efficiency and scalability. They normally partition the group members into local groups and allocate one server for each local group to detect and recover packet loss. One common problem is how the server recovers the lost packet in the case that the server itself does not receive it. The usual solution is either to send requests to some upstream servers/source or to construct a tree-based hierarchy to organize the servers for recovery. However, these solutions may lead to long recovery latency. This paper presents a server relay recovery strategy (SRRS) for servers to achieve low recovery latency and low bandwidth usage for recovery. The basic idea is for each server to distributively compute and maintain a prioritized peer list that leads to minimal expected relay recovery latency. Our simulation results show that when the server distribution is not dense, SRRS outperforms SRM (scalable reliable multicast) and RMA (reliable multicast architecture) on both recovery latency and bandwidth usage in Internet-like topologies.