Asynchronous Web Services Communication Patterns in Business Protocols

Asynchronous interactions are becoming more and more important in the realization of complex B2B Web applications, and Web services are at the moment the most innovative and well-established implementation platform for communication between applications. This paper studies the existing business protocols for Web services interactions, compares their expressive power, extracts a set of patterns for implementing asynchrony, studies the trade-offs and the typical usage scenarios of the various patterns, and finally proposes a sample application that has been implemented based on these patterns. The application has been designed using a high-level modeling language for Web applications, thus showing that the studied patterns can be applied at a conceptual level as well as directly at implementation level.