Automated Web Service Composition Methods and Tradeoffs

This paper examines the use of constraint-based configuration for the composition of Web Services. Web Services are widely assumed to represent the basis for the next generation of flexible distributed applications in B2B E-commerce, and the composition of complex applications from individuals services has attracted much attention. We show how this composition problem can be addressed at increasing levels of semantic content embedded in the description of services, moving from purely manual composition to describing service matching as a configuration problem that can be solved using constraint-based methods. We examine the restrictions imposed by Semantic Web ontology languages and providing a succinct and high level mechanism for imposing the different boundary conditions resulting from the multilayered application environment. We give an example showing the configuration process for a simple example problem, discuss the ramifications of the full composition problem, and describe the resulting system architecture.