A DAML-based repository for QoS-aware semantic Web service selection

The Web is moving toward a collection of interoperating Web services. Achieving this interoperability requires dynamic discovery of Web services on the basis of their capabilities. The capability of a service can be properly determined by using not only its functional description (or service interface), but also its quality attributes as judged by previous users of the service. We develop a service repository that extends UDDI registries. This repository combines an ontology of attributes with evaluation data. We base our repository on a new query and manipulation language based on DAML. Our language includes support for a rich set of operations, which are needed to maintain an attribute ontology, publish services, rate services, and select services based on their functional attributes as well as evaluations by others. We have implemented our approach and evaluated its practical completeness via a number of key query and manipulation templates.