Enhanced Distributed Hash Tables for Complex Queries

Peer-to-peer file sharing systems have become a very popular way of sharing large number of files over a distributed environment. One of the principal ingredients of such systems is a lookup service which maps a key denoting a file to a location storing the file. Dynamic hash tables (DHT´s) were recently proposed as a means of supporting such a lookup service in a completely distributed manner. They have many desirable properties, but suffer from one serious drawback-in order to locate a file, we must have a precise knowledge of the key representing it. In this paper, we propose a lookup service which supports complex queries and has all the advantages of DHT´s. We also compare our proposed method with PIER , another recently proposed peer-to-peer system for answering complex queries. Our experiments show that our method results in better utilization of the network than PIER