Semantic Web and Peer-to-Peer Decentralized Management and Exchange of Knowledge and Information

Just like the industrial society of the last century depended on natural resources, today’s society depends on information and its exchange.

Semantic Web technologies address the problem of information complexity by providing advanced support for representing and processing distributed information, while peer-to-peer technologies address issues of system complexity by allowing flexible and decentralized information storage and processing. Systems that are based on Semantic Web and peer-to-peer technologies promise to combine the advantages of the two mechanisms. A peer-to-peer style architecture for the Semantic Web will avoid both physical and semantic bottlenecks that limit information and knowledge exchange.

Staab and Stuckenschmidt structured the selected contributions into four parts: Part I, "Data Storage and Access", prepares the semantic foundation, i.e. data modelling and querying in a flexible and yet scalable manner. These foundations allow for dealing with the organization of information at the individual peers. Part II, "Querying the Network", considers the routing of queries, as well as continuous queries and personalized queries under the conditions of the permanently changing topological structure of a peer-to-peer network. Part III, "Semantic Integration", deals with the mapping of heterogeneous data representations. Finally Part IV, "Methodology and Systems", reports experiences from case studies and sample applications.

The overall result is a state-of-the-art description of the potential of Semantic Web and peer-to-peer technologies for information sharing and knowledge management when applied jointly. It serves researchers in academia and industry as an excellent and lasting reference and source of inspiration.

Peer-to-Peer and Semantic Web.- Peer-to-Peer and Semantic Web.- Data Storage and Access.- An RDF Query and Transformation Language.- RDF and Traditional Query Architectures.- Query Processing in RDF/S-Based P2P Database Systems.- Querying the Network.- Cayley DHTs — A Group-Theoretic Framework for Analyzing DHTs Based on Cayley Graphs.- Semantic Query Routing in Unstructured Networks Using Social Metaphors.- Expertise-Based Peer Selection.- Personalized Information Access in a Bibliographic Peer-to-Peer System.- Designing Semantic Publish/Subscribe Networks Using Super-Peers.- Semantic Integration.- Semantic Coordination of Heterogeneous Classifications Schemas.- Semantic Mapping by Approximation.- Satisficing Ontology Mapping.- Scalable, Peer-Based Mediation Across XML Schemas and Ontologies.- Semantic Gossiping: Fostering Semantic Interoperability in Peer Data Management Systems.- Methodology and Systems.- A Methodology for Distributed Knowledge Management Using Ontologies and Peer-to-Peer.- Distributed Engineering of Ontologies (DILIGENT).- A Peer-to-Peer Solution for Distributed Knowledge Management.- Xarop, a Semantic Peer-to-Peer System for a Virtual Organization.- Bibster — A Semantics-Based Bibliographic Peer-to-Peer System.

PD Dr. Steffen Staab is a senior lecturer in applied computer science at the University of Karlsruhe. He has earned a M.S.E. from University of Pennsylvania, a Dr. rer. nat. from University of Freiburg and his habilitation from University of Karlsruhe. He has done research in the fields of computational linguistics, text mining, ontology engineering, knowledge management, and peer-to-peer. He has co-authored over 120 refereed publications and published 7 books, including a Handbook on Ontologies. In 1999, Steffen Staab has co-founded Ontoprise, the first Semantic Web company. He serves on the editorial board of IEEE Intelligent Systems, Journal of Web Semantics, Journal of Human-Computer Studies and Journal of Information Technology and Tourism. Steffen Staab has co-chaired a large number of workshops and several conferences. Recently, he serves as an area chair of ECAI-2004, Semantic Web track chair of WWW-2005, and co-chair of STAIRS-2004.

Dr. Heiner Stuckenschmidt Heiner Stuckenschmidt holds a post-doc position in the Knowledge Representation and Reasoning Group at the Vrije Universiteit Amsterdam where he received his PhD for work on Ontology-Based Information Sharing on the Semantic Web. He works includes Semantic Web related topics such as ontology languages, knowledge-based meta data management and robust and scalable terminological reasoning. Before moving to Amsterdam, he was employed as a researcher and lecturer at the University of Bremen. His research activities in Bremen included the application of ontologies for information sharing in web based information systems with a special focus on semantics-preserving information integration and spatially related information. He is organizer of a series of workshops on ontologies at international conferences (IJCAI’01, ECAI’02, IJCAI’03) and member of program committees of several semantic web related conferences (SWWS’01, ISWC’02, WWW’03) and has held / will hold tutorial at different conferences (K-CAP 2001, IJCAI’03, ISWC’03). He is editor of a book on the application of ontologies in the cadastral domain the author of a book on Information Sharing on the Semantic web and has published more than 40 paper in international journals, conferences and workshops.