Query routing and processing in schema-based P2P systems

Recently, the peer-to-peer (P2P) paradigm has emerged, mainly by file sharing systems such as Napster and Gnutella and in terms of scalable distributed data structures. Due to the decentralization, P2P systems promise an improved robustness and scalability and therefore open also a new view on data integration solutions. However, several design and technical challenges arise in building scalable P2P-based integration systems. We address one of them: the problem of distributed query processing. We discuss strategies of query decomposition and routing based on different kinds of routing indexes and present results of an experimental evaluation.