Toward a Unified View of Data and Services

The research on data integration and service discovering has involved from the beginning different (not always overlapping) communities. Therefore, data and services are described with different models and different techniques to retrieve data and services have been developed. Nevertheless, from a user perspective, the border between data and services is often not so definite, since data and services provide a complementary vision about the available resources.In NeP4B (Networked Peers for Business), a project funded by the Italian Ministry of University and Research, we developed a semantic approach for providing a uniform representation of data and services, thus allowing users to obtain sets of data and lists of web-services as query results. The NeP4B idea relies on the creation of a Peer Virtual View (PVV) representing sets of data sources and web services, i.e. an ontological representation of data sources which is mapped to an ontological representation of web services. The PVV is exploited for solving user queries: 1) data results are selected by adopting a GAV approach; 2) services are retrieved by an information retrieval approach applied on service descriptions and by exploiting the mappings on the PVV.In the tutorial, we introduce: 1) the state of the art of semantic-based data integration and web service discovering systems; 2) the NeP4B architecture.