Distributed invocation of composite Web services

Web services provide a useful means to integrate heterogeneous applications distributed over the Internet based on XML and Web technologies. This paper presents an approach to execute hierarchically interacting web services efficiently. We provide a system architecture which can distribute invocations of web services over service providers by exploiting intensional XML messages embedding external web service calls. We also propose a greedy heuristic algorithm to generate an efficient strategy of executing web service calls, which can improve overall performance of distributed web service systems on the Internet.