Extending THREDDS middleware to serve OGC community

Abstract. As far as interoperability is concerned, in a service-oriented framework, it is possible to distinguish different service tiers; each tier contains systems and tools which implement that tier's specific task. The present paper analyses such a framework for the Earth Sciences and the GIS information communities. For the Earth Sciences community, the heterogeneity of existing protocols and data models is outlined, considering the experience of the Unidata community. For the GIS community, the interoperability opportunities laid by the OGC's specifications are briefly introduced. The need of achieving the two communities' frameworks interoperability, and its importance for science Digital Library applications are introduced. A solution is presented and discussed; it is based on the following technologies: THREDDS Data Server, OGC WCS/WFS and ncML-GML. An OGC interoperability experiment, which tests the proposed solution, is briefly presented.