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In computing, the Open Geospatial Consortium Web Feature Service Interface Standard (WFS) provides an interface allowing requests for geographical features across the web using platform-independent calls. One can think of geographical features as the "source code" behind a map, whereas the WMS interface or online tiled mapping portals like Google Maps return only an image, which end-users cannot edit or spatially analyze. The XML-based GML furnishes the default payload-encoding for transporting geographic features, but other formats like shapefiles can also serve for transport. In early 2006 the OGC members approved the OpenGIS GML Simple Features Profile.〔http://portal.opengeospatial.org/files/?artifact_id=15201〕 This profile is designed both to increase interoperability between WFS servers and to improve the ease of implementation of the WFS standard. The OGC membership defined and maintains the WFS specification. Numerous commercial and open-source implementations of the WFS interface standard exist, including the open-source reference implementations GeoServer and deegree. The OGC Implementing Products page〔 http://www.opengeospatial.org/resource/products/byspec/?specid=50 〕 provides a comprehensive list of WFS implementations. ==Overview == The WFS specification defines interfaces for describing data manipulation operations of geographic features. Data manipulation operations include the ability to: * get or query features based on spatial and non-spatial constraints * create a new feature instance * delete a feature instance * update a feature instance The basic Web Feature Service allows querying and retrieval of features. A transactional Web Feature Service (WFS-T) allows creation, deletion, and updating of features. A WFS describes discovery, query, or data transformation operations. The client generates the request and posts it to a web feature server using HTTP. The web feature server then executes the request. The WFS specification uses HTTP as the distributed computing platform, although this is not a hard requirement. There are two encodings defined for WFS operations: * XML (amenable to HTTP POST, or SOAP) * Key/value pairs (encoded in HTTP GET query strings, to perform remote procedure calls)〔http://portal.opengeospatial.org/files/?artifact_id=36263&format=pdf〕 In the taxonomy of Web Services, WFS is best categorized as a non-RESTful RPC type service. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Web Feature Service」の詳細全文を読む スポンサード リンク
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