Service composition

Abstract

One of the striking advantages of Web Service technology is the fairly simple aggregation of complex services out of a library of other composite or atomic services. The same is expected to hold for the domain of Semantic Web Services such as those specified in WSMO or OWL-S. The composition of complex services at design time is a well-understood principle which is nowadays supported by classical workflow and AI planing based composition tools (cf. Chapter 4). In CASCOM, we developed two composition planners for OWL-S services, OWLS-XPlan and MetaComp, together with an approach to heuristically prefiltering the set of all available services which are delivered by the SMA (cf. Chapter 10) to significantly reduce the search space for both planners. Accordingly, the CASCOM service composition planning agent, called SCPA, can be configured to use one of the planners and either exploiting the pre-filtering module, or not. This chapter is structured as follows. We briefly summarize the CASCOM composition planner agent SCPA, followed by the detailed description of the prefiltering module, and both the OWLS-XPlan and MetaComp planning modules of the SCPA.