Interactive Discovery and Composition of Complex Web Services

Among the most important expected benefits of a global service oriented architecture leveraging web service standards is an increased level of automation in the discovery, composition, verification, monitoring and recovery of services for the realization of complex processes. Most existing works addressing this issue are based on the Ontology Web Language for Services (OWL-S) and founded on description logic. Because the discovery and composition tasks are designed to be fully automatic, the solutions are limited to the realization of rather simple processes. To overcome this deficiency, this paper proposes an approach in which service capability descriptions are based on full first order predicate logic and enable an interactive discovery and composition of services for the realization of complex processes. The proposed approach is well suited when automatic service discovery does not constitute an absolute requirement and the discovery can be done interactively (semi-automatically) with human expert intervention. Such applications are, for instance, often met in e-science. The proposed approach is an extension and adaptation of the compositional information systems development (CISD) method based on the SYNTHESIS language and previously proposed by some of the authors. The resulting method offers a canonical extensible object model with its formal automatic semantic interpretation in the Abstract Machine Notation (AMN) as well as reasoning capabilities applying AMN interactively to the discovery and composition of web services.