Modeling and verification for data-centric web services

We propose a model for a class of Web services which are powered by relational databases and respond to users by querying the underlying database as well as the state information of interaction. Our model can be viewed as an extension of WSDL specification where schemas of service operations specify not only input-output signatures but also data constraints, control-flow constraints, and state/output/action rules. The control-flow and more complex data-aware temporal properties about interactions between services and users are specified in Linear Temporal Logic (LTL) and its extension Linear Temporal First-Order Logic (LTL-FO). We have proved it is feasible to existing tools (e.g. SPIN, WAVE) to verify such properties.