Describing, Verifying and Developing Web Service Using the B-method

It is necessary to guarantee the validity of Web services and their composition. Traditional approaches transform the BPEL4WS specification into other formal models and then check them. Unfortunately, if we could not find the proper composition of services to fulfil the request but have to develop parts of services ourselves, the models used to verify are almost useless in other development steps. The B-method is a state model-based, formal specification notation that has strong structuring mechanisms and good tool support. Furthermore, refinement, a key concept in the B-method, allows one to start from a high-level specification and then gradually refine it into an implementation. There are some tools which have been developed for the automatic refinement check. Therefore, modeling for Web services and their composition, and then verifying the B models, and refining, and finally even implementing parts of the B models if necessary with the help of the tools of B, is proposed in this paper