Extending Web Service Composition Languages with Semantic Data Flow

Most of the work on automated Web service composition has focused so far on composition of stateful Web services. This level of composition so called ldquoProcess Levelrdquo considers Web services with their internal and complex behaviours. At process level formal models such as State Transition Systems (STS from now) or Interface Automata are the most appropriate models to represent the internal behaviour of stateful Web services. However such models focus only on semantics of their behaviours and unfortunately not on semantics of actions and their parameters. In this paper, we suggest to extending the STS model in the latter direction w.r.t the semantic Web. This semantic enhancement of STS so called S2TS will enable to model semantics of internal behaviours and semantics of their actions together with their input and output parameters. Secondly, we will focus on automated generation of data flow (or the process to perform automated assignments between services of a composition). Thus we do not restrict to assignments of exact parameters (which is practically never used in industrial scenario) but extend assignments to semantically close parameters (e.g., through a subsumption matching). Our system is implemented and interacting with Web services dedicated on Telecom scenarios. The preliminary evaluation results showed high efficiency and effectiveness of the proposed approach.