Web Service Compositions: From XML Syntax to Service Models

Track: Metadata and Semantics, Large-Scale Architectures

Audience Level: Technical view

Time: Wednesday, November 16 16:00

Author: Howard Foster, Imperial College London

Keywords: Web Services, XML, BPEL4WS, Model-based Analysis, Verification, Validation


This paper presents a rigorous approach to specifying, modelling, verifying and validating the behaviour of web service compositions with the goal of simplifying the task of designing coordinated distributed services and their interaction requirements. We address these issues through the use of rigorous software process analysis techniques, specifying semantics for web service composition standards and by providing an accessible, mechanical tool (as a plug-in to the Eclipse development environment), which automates the tasks involved. As web technology has evolved, an emphasis has been placed on providing ease of design for both visual content and functional services for users. Web Services however, concentrate on the view of systems inter-operating with other systems rather than that of actual human actors, yet the concepts for ease of design are highly related and desired. Firstly, this paper presents a model-based approach to the semantics of web service composition XML documents built upon formal verification, validation and simulation techniques, utilising scenario-based design and implementations built in service composition standards. Secondly, the work assigns the semantics of compositions through the use of Labelled Transition Systems (LTS) in the form of Finite State Processes (FSP). Thirdly, an environment is described forming a tool to assist in undertaking the approach.