Geographic data, or “geodata,” data which describes phenomena directly or indirectly associated with a location (and time, and orientation) relative to the surface of the Earth, has been collected in digital form for more than 30 years.
The Geographic Information Systems (GIS) are able to manage those data so they permit their input, representation, storage, search, analysis and transformation. But the natural diversity of commercial informatic systems is a cause for difficulties obtained in the access to the information in distributed and heterogeneous environments. Currently, the key question in terms of GIS is the interoperability that is the capacity of independent systems to be able to exchange information in a transparent way, in spite of, internally, the storage is made in different, potentially incompatible formats. Only when different GIS will be able to freely exchange all types of digital spatial information and, by means of a network, to be able to execute software to manipulate that information, it will be truly possible to speak about interoperability. This is a hot point and, as an example, it must be referred that the United States Government spends more than 4 billion dollars per year in data conversion and the European Union has much more complex problems in data sharing, due to a more heterogeneous set of institutions.
One prove of the necessity to increase the interoperability in GIS is the dynamism observed in the context of OpenGIS Consortium. Their main objective is to solve the data sharing problems, moving the GIS from their current status (based on proprietary and monolithic databases) towards the new philosophies, based on Components and Distributed Computing, where the interoperability is a essential requisite. The Distributed Objects Technology permits the interoperability between applications, in homogeneous or heterogeneous environments. The OpenGIS Specification aims to extend this information technologies evolution to the area of georeferenced data and to the geoprocessing applications.
The current project has as main objectives to frame the OpenGIS Specification in the current Distributed Objects Technology; evaluate its importance in the interoperability between GIS applications; specify and implement an interface to permit the communication, following the concepts of distributed objects (CORBA, DCOM, EntireXD COM) between client applications and a structure of distributed database that are supported by technologies adherent to the OpenGIS specification.