Mediating heterogeneous Web services

Web services technology provides the foundation for a new business opportunity, i.e., the possibility of providing value-added Web services. However, building value-added services in this new environment is not a trivial task. Due to many singularities of the Web service environment, such as the inherent structural and behavioral heterogeneity of Web services, in addition to their strict autonomy, it is not possible to rely on current models and solutions to build and coordinate compositions of Web services. We present a mediation service layer within an architecture, named WebTransact, which provides the necessary mechanisms for homogenizing heterogeneous Web services. Such architecture separates the task of aggregating and homogenizing heterogeneous Web services from the task of specifying transaction interaction patterns, thus providing a new general mechanism to deal with the complexity introduced by a large number of Web services.