Peer Content Groups for Reliable and Transparent Content Access in P2P Networks

This work presents a strategy based on the group communication for transparent and robust content access in P2P networks. Instead of accessing a single peer for obtaining the desired content, a user request is received and processed by a group of peers. A Peer Content Group (PCG) guarantees continuous access to content even if members crash or leave the system provided at least one member remains fault-free. Each PCG member is capable of independently serving the request. A PCG is transparent to the user, as the group interface is identical to the interface provided by a single peer. A group member is elected to serve each request. A fault monitoring component allows the detection of member crashes. If the peer that is serving a request crashes, another group member is elected to continue providing the service. Peer election and replacement are transparent to client peers. The PCG and a P2P file sharing application were implemented in the JXTA platform. Experimental results are presented showing the latency of group operations and system components.