Integrating Directories and Service Composition

A major challenge in web service composition is that there will be a large number of often redundant web services that can be used. Furthermore, the set of services is unbounded and changes dynamically. Consequently, web service composition methods have to be tightly integrated with directories or search engines for such services. We introduce an approach for creating scalable directories of web services modelled by DAML-S service descriptions. Based on this approach, we develop a service composition algorithm that incrementally queries the directory. Our contribution also includes an implementation of such a system that helped us in understanding the practical challenges in building a tool for service integration. The major novelty of our approach is that it is fully able to deal with partial matches, both in the directory and the planning algorithm.