Current service architecture description language and composition approaches consider simplistic method invocation. They pay less attention to the formal semantics and verification of service composition in the design, and less support property specifications and architecture validation. This paper presents an executable web service architecture model, Service-Oriented Software Architecture Model (SO-SAM), which is an extension of SAM (Software Architecture Model [16]) to the web service applications, and verification of web system properties in the design. SO-SAM describes each web service in terms of component and service composition in terms of connector separately. Furthermore, we validate SO-SAM model to prove that it facilitates the verification and monitoring of web services integration through translation to the Maude programming langauge, a high level language and high performance executable specification with the componentized and object-oriented design, as well as using model checking technique in the system design level. Finally, a case study of the validation of the model is demonstrated.
