Tree-Based Consistency Maintenance Scheme for Peer-to-Peer File Sharing Systems

In this paper, we propose a new consistency maintenance scheme for P2P file sharing systems which allow end-users to update shared files. The basic idea of the proposed scheme is to construct a static tree for each file to efficiently propagate the update information to all replica peers. The link to the root in a tree is acquired by referring to a Chord ring which registers the mapping from the set of shared files to the set of roots of the trees. The performance of the scheme is evaluated by simulation. The result of simulations indicates that: 1) the proposed scheme reduces the number of messages in a conventional scheme by 54%, 2) the propagation delay of update messages is shorter than the conventional scheme, and 3) the increase of the delay due to peer churns is effectively bounded provided that the percentage of leaving peers is less than 40%.