A Feedback-Based Approach to Reduce Duplicate Messages in Unstructured Peer-To-Peer Networks

Abstract

Resource location in unstructured P2P systems is mainly performed by having each node forward each incoming query message to all of its neighbors, a process called flooding. Although this algorithm has excellent response time and is very simple to implement, it creates a large volume of unnecessary traffic in today’s Internet because each node may receive the same query several times through different paths. We propose an innovative technique, the feedback-based approach that aims to improve the scalability of flooding. The main idea behind our algorithm is to monitor the ratio of duplicate messages transmitted over each network connection, and not forward query messages over connections whose ratio exceeds some threshold. Through extensive simulation we show that this algorithm exhibits significant reduction of traffic in random and small-world graphs, the two most common types of graph that have been studied in the context of P2P systems, while conserving network coverage.