A knowledge-based approach for semantic service composition

The successful application of Grid and Web Service technologies to real-world problems, such as e-Science, requires not only the development of a common vocabulary and meta-data framework as the basis for interagent communication and service integration but also the access and use of a rich repository of domain-specific knowledge for problem solving. oth requirements are met by the respective outcomes of ontological and knowledge engineering initiatives. In this paper we discuss a novel, knowledge-based approach to resource synthesis (service composition), which draws on the functionality of semantic web services to represent and e pose available resources. The approach we use e ploits domain knowledge to guide the service composition process and provide advice on service selection and instantiation. The approach has been implemented in a prototype workflow construction environment that supports the runtime recommendation of a service solution, service discovery via semantic service descriptions, and knowledge-based configuration of selected services. The use of knowledge provides a basis for full automation of service composition via conventional planning algorithms. Workflows produced by this system can be e ecuted through a domain-specific direct mapping mechanism or via a more fluid approach such as WSDL-based service grounding. The approach and prototype have been used to demonstrate practical benefits in the conte t of the Geodise initiative.