Brief Announcement: An Adaptive Randomised Searching Protocol in Peer-to-Peer Systems Based on Probabilistic Weak Quorum System

Abstract

Searching problem, which is to identify the peer that has some target resource, is an important and unique problem in Peer-to-Peer (P2P) file sharing systems. Since P2P file sharing systems maintain large and dynamic set of peers, the searching protocol is desired to be scalable and adaptive. To achieve such requirements, many kinds of search protocols are proposed. As one of those protocols, the searching protocol based on Probabilistic Weak Quorum System (PWQS) is recently proposed [1]. The principle of this protocol is as follows: In advance, a number of indices (location informations of an object) of each object are disseminated to randomly selected peers. When searching, the searcher sends a number of queries to randomly selected peers. If a query reaches a peer holding the index of the target object, search succeeds. It is shown that the protocol has advantages in the point of scalability, load balance and fault-tolerance.