Discovering Web Services Using Behavioural Constraints and Ontology

The ability to locate useful on-line Web Services is becoming critical for today’s service-oriented business applications. A number of efforts have been put to enhance the service discovery process by using conceptualised knowledge, called ontology, of particular service domains to describe service characteristics. This paper presents an ontology-based approach to enhance descriptions of Web Services that are expressed in WSDL with ontology-based behavioural information, i.e. input, conditional/unconditional output, precondition, and conditional/unconditional effect of the services. Having a service ontology associated with each Web Service description, queries for services based on behavioural constraints can benefit from inferring semantics of the service from the service ontology. The service discovery process becomes closer to discovery by service semantics or behaviour, in contrast with discovery by matching of service attributes values – the mechanism that is supported currently by Web Services.