W3C | Submissions

Team Comment on Web Service Semantics - WSDL-S Submission

W3C is pleased to receive the Web Service Semantics - WSDL-S Submission from IBM.

This submission proposes a common mechanism to associate semantic annotations with Web services that are described using Web Service Description Language (WSDL). It is intended to be used as a starting point toolkit to build upon for other Semantic Web Services related efforts. WSDL-S relies on both the WSDL and XML Schema extension mechanisms to reference external semantic models, without constraining to a particular semantic representation language.

The WSDL-S submission defines extension elements input, output, precondition and effect. While input and output are known concepts in WSDL 2.0, precondition and effects are not part of it. All four elements are defined in the IOPE model, as described in the OWL-S Submission. The precondition element, like in the two examples given in the document ("must have an existing account with this company" or "Only US customers can be served"), as well as the effect element, has been discussed during the Constraints and Capabilities Workshop.

Related Work

This Member Submission is related to the W3C WSDL 2.0 specification, developed by the Web Services Description Working Group and, for a significant part of the work, to XML Schema.

It also refers to RDF and OWL as semantic representation languages, but does not preclude other approaches.

Next Steps

The area of semantic annotations in Web services descriptions is an obvious first step in bridging Web services with Semantic Web technologies. The expression of semantics could help resolving some class of Web services applications

The W3C is working on a Working Group charter on the area of semantic annotations in Web services descriptions, as announced in the advance notice about Semantics for Web services. This submission addressed the second short-term development of providing generic annotations to specify semantics in Web services descriptions. Further work would be needed to integrate with other Semantic Web technologies, such as SPARQL.

The W3C will also ensure that a careful review and analysis of Use Cases for semantics in Web services applications, in order to plan future work, following the semantic annotations for WSDL, towards an integrated model of semantics for Web services.

The W3C Membership will be invited soon to review the semantic annotation for Web services description Working Group charter and advise on future work in the area of semantics in Web services.


Author: Carine Bournez