Interface Decomposition for Service Compositions

Service-based applications can be realized by composing existing services into new, added-value composite services. The external services with which a service composition interacts are usually known by means of their syntactical interface. However, an interface providing more information, such as a behavioral specification, could be more useful to a service integrator for assessing that a certain external service can contribute to ful fill the functional requirements of the composite application. Given the requirements specification of a composite service, we present a technique for obtaining the behavioral interfaces - in the form of labeled transition systems - of the external services, by decomposing the global interface speci fication that characterizes the environment of the service composition. The generated interfaces guarantee that the service composition fulfills its requirements during the execution. Our approach has been implemented in the LTSA tool and has been applied to two case studies.