Modern Geographical Information Systems (GIS) [1] provide a service-oriented architecture for interacting with geographical data sets and related maps. Web-based GIS systems are architected around the same principles as more general Web service systems based on SOAP [2], WSDL [3], and REST. Mirroring the World Wide Web Consortium and OASIS Web service standards-making bodies, the Open Geospatial Consortium [5] defines open standards for messages, XML data formats, and access protocols that are specific to the GIS community. In addition to OGC-based services, there are many companies (such as ESRI and AutoDesk) that provide proprietary, commercial solutions. Services from these various providers are not normally interoperable.
Read the rest of this entry »