Message replication in unstructured peer-to-peer network

Recently, unstructured peer-to-peer (P2P) applications have become extremely popular. Searching in these networks has been a hot research topic. Flooding-based searching, which has been the basis of real-world P2P networks is inherently inefficient and unscalable. Replication has proven to be an effective strategy to improve efficiency and scalability of unstructured P2P networks. Previous research has largely focused on replicating resources or their references. This paper considers a replication solution from a different perspective; we investigate replicating messages and its effect on overloading problem. We propose two message replication strategies. The distance-based message replication technique replicates the query messages at different topological regions of the network. The landmarks-based technique further optimizes the performance by considering both the topology as well as the physical proximities of the peers of the overlay. Our experiments show that the proposed techniques substantially reduce the message traffic in the overlay while maintaining query performance.