Semantic Web Services Discovery based on Structural Ontology Matching

In this paper, we present an approach to semantic-based web service discovery and a prototypical tool based on syntactic and structural schema matching. It is based on matching an input ontology, describing a service request, to web services descriptions at the ‘syntactic level’ through Web Services Description Language (WSDL) or, at the semantic level, through service ontologies described with languages such as Ontology Web Language for Services (OWL-S), Web Services Modelling Ontology (WSMO), Semantic Web Services Framework (SWSF) and Web Services Description Language Semantics (WSDL-S). The different input schemas, WSDL descriptions, Ontology Web Language (OWL) ontologies, OWL-S, WSMO, SWSF and WSDL-S components are represented in a uniform way by means of directed rooted graphs, where nodes represent schema elements, connected by directed links of different types, e.g., for containment and referential relationships. On this uniform internal representation, a number of matching algorithms operate, including structural-based algorithms (Children Matcher, Leaves Matcher, Graph and SubGraph Isomorphism) and syntactical ones (Edit Distance (Levenshtein Distance or LD) and Synonym Matcher (through the WordNet synonyms thesaurus)).