GSON: A group based hierarchically structured overlay network

In a structured Peer-to-Peer (P2P) overlay network, the stability of the entire network will be greatly affected by simultaneous join-in and drop-out of large amount of nodes. Aiming at reducing the overhead of handling this activity, we propose a group-based hierarchically structured overlay network, GSON. GSON is also a structured P2P overlay network using Distributed Hash Table (DHT). In GSON, nodes that are physically close to each other or under a common administrative control form a group by using a self-organizing protocol. Each group has a delegate to join the DHT on behalf of other nodes in the group. The information about the resource and membership is shared within the group. The delegate is responsible for passing information to all group members and publishing group resource to other groups. The resource of each group is mapped into the DHT. Simulation results show that GSON is more scalable, and can reach stable state more quickly than normal Chord system under the circumstances that a large number of nodes joining and quitting the system simultaneously.