Reusable Web Services

Designing systems of asynchronous web services is challenging. Addressing the design in terms of component reuse helps address important questions that need to be answered if dynamic configuration of business solutions from web services is to be achieved. The fact that the components are web services doesn’t mean that all the problems of reuse have been solved. An architecture for dealing with reuse and dynamic reconfiguration, based on stateless services and stateful messages, is investigated. A notation for describing the flow of documents in such a system is introduced. This is shown to be effective at describing the behaviour of components, a necessary part of designing reusable components, especially those that participate in long-running, asynchronous interactions.