Semantic Web and Peer-to-Peer Networks

Decentralized Knowledge Management and Information Exchange

The idea for the Semantic Web  brings interesting ideas for revolutionary approaches in the fields such as knowledge management. Knowledge Management (KM) becomes one of the essential driving forces for the existence of large communities. However, searching through the knowledge bases is very limited. The Semantic Web technologies promise concept alignment and powerful search features to be incorporated into knowledge management systems. But due to the client-server architecture upon which KM systems most often rely on, appearance of physical bottlenecks are very likely to happen. Therefore, an alternative architecture appropriate for large-scale systems is needed. As you already may guess, here flat networks come into play - the Peer-to-Peer (P2P) systems. 

P2P systems are not only scalable, but improve their performances as new nodes join the network. This unique feature gives them suitable ground for all sharing software applications. However, searching through these networks is limited to keyword search only, and different peers may name same resources differently, so it is obvious that it lacks semantics when resources with anonymous peers.

By combining Semantic Web technologies and P2P networks, could possibly bring ultimate conditions for advanced knowledge management techniques. Distributing knowledge accross different transparent physical locations and also providing peers to use their own views upon same data, can bring tremendous change in the evolution of the Semantic Web.  At first glance, it seems like an extraordinary idea - it would be wonderful if I could share a file with other peers who would be able to understand what it is and how it is related with other files someone else owns. Also, KMSs could distribute their knowledge on different peers, possibly with previous domenization of the knowledge in order to boost performances.

But if peers are free to annotate the resources they share with others, how will the knowledge ( ontology ) alignment occur ? There must be some kind of common mechanism for annotation so that alignment happens automatically and peer agents will be able to identify the relation of the resources shared. One suggested approach is to use small common vocabularies among peers. Then the peer agents will be able to align the knowledge automatically. But the question of performance for such large-scale system is yet to be proved as no real Semantic P2P application has been deployed.

Note: For anyone interested in this topic, I recommend the book: Semantic Web and Peer-to-Peer: Decentralized Management and Exchange of Knowledge and Information. I will continue the discussion once I finish reading this book.