SAWSDL, mediation and XQUERY for web services discovery

Web services have been adopted by large industrial and commercial organizations to achieve interoperability between distributed systems. The interaction between web services components is done through publication, research, discovery and then invocation based on the service's description. However, their publication in an UDDI registry doesn't offer enough description of the service offering. The main idea described in this paper is about having a semantic description of web services (using SAWSDL) and then storing their functionality, during the publication phase, in a register named 'semantic links base'. This base represents the mediator between the service requestor and the service provider and would minimize the search time during the discovery step, because the mapping between the request concepts and the Web services are known in advance. The Web services discovery process is about finding these mappings between the user query, which is defined in a unified manner by referring to an ontology, and the web services functionality. The user request is translated into a query on the 'semantic links base' as well as the UDDI registry. The result returned can then be used as entry point for another query.