What is Geospatial Web Services

Spatial information is an essential component in almost all decision support system due to the capability it provides for analyzing anything that has reference to the location on earth. Spatial data generally provides thematic information of different aspects over a region. Geospatial information, a variant of spatial information, is generally collected on thematic basis, where individual organizations are involved on any particular theme. Geospatial thematic data is being collected from decades and huge amount of data is available in different organizations (Stoimenov, Dordevi´c, & Stojanovi´c 2000). Information communities find it difficult to locate and retrieve required geospatial information from other geospatial sources in reliable and acceptable form. The problem that has been incurred is the lack of standards in geospatial data formats and storage/access mechanism (Devogele, Parent, Spaccapietra, 1998). Heterogeneity in geospatial data formats and access methods poses a major challenge for geospatial information sharing among a larger user community. With the growing need of geospatial information and widespread use of Internet has fostered the requirement of geospatial information sharing over the Web. The Geo-Web (Lake, Burggraf, Trninic, & Rae, 2005) is being envisioned to be a distributed network of interconnected geographic information sources and processing services that are: • Globally accessible, that is, they live on the internet and are accessed through standard Open Geospatial Consortium (OGC) and W3C interfaces, • Globally integrated data sources that make use of standard data representation for sharing and transporting geospatial data. Unless a standard means for geospatial information sharing is developed, interoperability cannot be realized. Without successful interoperability approaches, the realization of Geo-Web is not possible. Geo-Web is being developed to address the need for access to current and accurate geospatial information from diverse geospatial sources around the world. The National Spatial Data Infrastructure (NSDI) initiative has been taken by many nations for providing integrated access of geospatial information (Budak, Sheth, & Ramakrishnan, 2004). Actual data will be kept under the jurisdiction of the organization producing that data. A user will be interested in availing geospatial services through well-defined interface. Without some internationally agreed upon standards for geospatial data and computational methodology, this cannot be made into existence. This chapter discusses several issues towards geospatial interoperability and adoption of geography markup language (GML) (Cox, Cuthbert, Lake, & Martell, 2001; Lake et al., 2005) as a common geospatial data format. The associated technologies that can be used for realizing geospatial interoperability have also been discussed.