Cluster-based proactive replication of multimedia files in peer-to-peer networks

In this paper, we address the issue of multimedia content replication over peer-to peer networks. We use the concept of semantic proximity that exploits the file exchange patterns exhibited among peer users so as to decompose the network into semantic clusters. Through the optimization of the search process that exploits semantic associations between peer nodes, we derive a semantic organization of the network which is then used for applying efficient cluster-based content replication strategies. Two different schemes are examined; the unrestricted and the restricted approach. The first one distributes multimedia content within peers of a cluster so that the average hop distance among nodes and objects weighted by the object popularity is minimized. This approach does not take into account any Quality of Service (QoS) guarantees. On the other handm the second scheme iteratively partitions the nodes of a cluster during each object replication based on a QoS violation criterion. The proposed algorithms are experimentally evaluated and compared with other approaches to demonstrate the efficiency of our proposed schemes.