Similarity Measures for Substituting Web Services

Web service substitution is one of the most advanced tasks that a composite Web service developer must achieve. Substitution occurs when, in a composite scenario, a service operation is replaced to improve the composition performance or fix a disruption caused by a failing service. To move the automation of substitution forward, a set of measures, considering structure and functionality of Web services, are provided. Most of current proposals for the discovery and matchmaking of Web services are based on the semantic perspective, which lacks the precise information that is needed toward Web service substitution. This paper describes a set of similarity measures to support this substitution. Similarity measurement accounts the differences or similarities by the syntax comparison of names and data types, followed by the comparison of input and output parameters values of Web service operations. Calculation of these measures was implemented using a filtering process. To evaluate this approach, a software architecture was implemented, and experimental tests were carried on both private and public available Web services. Additionally, as is discussed, the application of these measures can be extended to other Web services tasks, such as classification, clustering and composition.