Graph-Based Matching of Composite OWL-S Services

Existing techniques for Web service discovery focus mainly on matching functional parameters of atomic services, such as inputs and outputs. However, one of the main advantages of Web services is that they are often composed into more complex processes to achieve a given goal. Applying such techniques in these cases, ignores the workflow structure of the composite process, and therefore may produce matches that are not very accurate. To overcome this limitation, we propose in this paper a graph-based method for matching composite services, that are semantically described as OWL-S processes. We propose a graph representation of composite OWL-S processes and we introduce a matching algorithm that performs comparisons not only at the level of individual components but also at the structural level, taking into consideration the control flow among the atomic components. We also report our preliminary results of our experimental evaluation.