Semantic Web Spaces: A Coordination Middleware for the Semantic Web

In a real world scenario Semantic Web applications must be capable to cope with the large scale, distributed, heterogeneous, unreliable and insecure environment of the World Wide Web if they are to truly represent added value to Web users. This includes issues of persistent storage, efficient reasoning, data mediation, scalability, distribution of data, fault tolerance and security. Semantic Web Spaces is a Linda-based coordination platform that aims at acting as a middleware which fulfills the mentioned requirements. Semantic Web Spaces allows the representation and management of Semantic Web information by extending the classical Linda model with new types of tuples e.g. RDF statements consisting of (subject, predicate, object) and new types of tuplespaces e.g. contexts/scopes expressing the view of a certain agent upon the entire information space.
As the tuplespace now no longer holds only data but also knowledge, the set of Linda operations is extended and refined:
  • The classical operations are defined to operate upon the tuples as data
  • To permit operations upon agent scope we add - addscope, rmscope
  • To add or remove tuples as knowledge we add - claim, retract
  • To query tuples as knowledge we define semantic matching relations and add - rdiftrue


  • Semantic Web Spaces
    Technical Report TR-B-04-11, Freie Universität Berlin, Germany, July 2004 - Robert Tolksdorf, Lyndon Nixon, Franziska Liebsch, Duc Minh Nguyen and Elena Paslaru Bontas
  • Enabling real world Semantic Web applications through a coordination middleware
    2nd European Semantic Web Conference ESWC2005, Heraklion, Crete, May 2005 - Robert Tolksdorf, Lyndon J. B. Nixon, Elena Paslaru Bontas, Duc Minh Nguyen, Franziska Liebsch
  • A Conceptual Model for Semantic Web Spaces
    Technical Report TR-B-05-14, Freie Universität Berlin, Germany, August 2005 - Elena Paslaru Bontas, Lyndon J B Nixon, Robert Tolksdorf
  • Using Semantic Web Spaces to realize Ontology Repositories
    Technical Report TR-B-05-15, Freie Universität Berlin, Germany, September 2005 - Elena Paslaru Bontas, Lyndon J B Nixon, Robert Tolksdorf
  • Towards a tuplespace-based middleware for the Semantic Web
    IEEE/WIC/ACM International Conference on Web Intelligence WI2005, Compiegne University of Technology, France, September 2005  - Robert Tolksdorf, Elena Paslaru Bontas, Lyndon J. B. Nixon
  • A co-ordination model for the Semantic Web
    21st ACM Symposium on Applied Computing, Workshop "Coordination Models, Languages and Applications", Bourgogne University, Dijon, France, April 2006  - Robert Tolksdorf, Elena Paslaru Bontas, Lyndon J. B. Nixon