Efficient Contents Sharing Using Differences between Versions in Peer-to-Peer Networks

This paper proposes an efficient contents sharing strategy using differences between their versions in Peer-to-Peer (P2P) networks. In this strategy, when a user requests a content item, he/she can get it by retrieving the other version of the content item and the difference from the requested version of the item, if the obtaining cost of the requested version of the content item is expensive. Furthermore, each content item is divided into several small blocks in order to be stored in the storages of peers without small and futile empty spaces.