OpenGIS specifications

Interoperability between servers

The OGC's willingness with the implementation of the specifications is to create a normative and accessible framework that facilitates the interoperability between the geoinformation servers. The specifications describe a series of standard languages ​​and protocols to be used by the different servers.

In these specifications does not mention nor the architecture, platform or programming languages ​​to use.

These documents, before being considered as an OpenGIS Implementation Specification, are developed and tested by various working groups within the OGC and, finally, put to the vote.

View available services in the IDEC's catalog.


Main OpenGIS specifications

Type of service

Short description

Web Map Service

This specification allows the end user to view 'maps' of different geospatial providers.

This standard understands a 'map' as a representation of geographic information through a digital image file that can be displayed on a computer screen. Maps produced by WMS are normally generated in image format (.png, .gif or .jpeg).

The WMS allows the visual superimposition of complex geographic information and distributed on different servers. That is, a client can make several requests to several servers at a time and can display different geographic data from different servers in the same environment (eg on your computer screen).

Web Feature Service

This specification is born of the will to have access to vectorial data; thus, it defines web operations of interface for the consultation and edition of vectorial features. This request for vectorial geoinformation comes to the client in GML language, which will facilitate its subsequent management.

Web Coverage Service

This standard defines interfaces and operations that allow access to geospatial 'coverages'.

The term 'coverage' refers to contents of the satellite image type, digital aerial photos, digital elevation data and any other element that can be represented through measurement points.

The response to a WCS request includes the metadata for the coverage and the coverage itself. Their pixels are encoded in specific binary format, such as GeoTIFF or NetCDF.

Web Map Tile Service

This specification allows storing and retrieving map data and does so by serving 'map' mosaics.

This specification is closely linked to WMS but is designed to allow better server performance when many concurrent requests are invoked. To improve performance, instead of creating a new image for each request, WMTS returns small generated pre-images (for example, PNG or JPEG) or reuses identical previous requests that follow a discrete set of tile arrays.

Web Processing Service

This standard provides rules for the standardization of input and output (requests and responses) for data processing services.

It describes how to access geospatial processes from a web interface. The processes include any calculation or process that operates on georeferenced raster or vector data, for example operations with polygons or databases.

Sensor Observation Service

This standard defines an interface and operations for accessing observations from sensors and sensor systems. It is a consistent standard for all systems and includes remote, in-situ, fixed and mobile sensors.

The response to the requests of the clients is constituted following the standard formats of observation and measurement of sensors (O&M and SensorML).

Catalog Service for the Web

This specification establishes how geospatial metadata cataloging and search services should be structured and implemented, establishing the minimum subset of metadata that is to be interrogated.

Web Map Context

It specifies how to describe in an XML file a project that contains a map view created from WMS connections. It allows:

- Create predefined views, thematic maps;

- Save and/or upload these views online;

Geography Markup Language

This XML sub-language allows the modeling, transport and storage of geoinformation.

Its importance lies in the fact that, at the computer level, it is constituted as a base language for the management and exchange of geoinformation between the different programs that use this type of data.

Keyhole Markup Language

It is an XML language focused on the description and visualization of the geoinformation in current and future web map management applications (2d and 3d).

This language was introduced by Google to the OGC with the aim of incorporating it as a standard. OGC and Google are currently working collaboratively to ensure this process.

Styled Layer Descriptor

It is a standard language that is born of the need on the part of the user to be able to symbolize and represent the geoinformation that comes to him from the server.

The SLD addresses the need for users and software to be able to control the visual representation of geospatial data. The language defines some style rules that both the client and the server can understand.

Other specifications