GML GeoShape Application Schema for use in internet standards developed by the IETF

This OGC Best Practices document defines an application schema of the Geography Markup Language (GML) version 3.1.1 for XML encoding of various geometric shapes required in the Presence Information Description Format (IETF RFC 3863) Location Object extension (PIDF-LO) - A Presence-based GEOPRIV Location Object Format (RFC 4119). The actual schema and supporting document was developed by Martin Thomson, Andrew Corporation.

From RFC 4119:

Because it satisfies REQ 2.5.1, this document works from the assumption that Geography Markup
Language (GML) 3.0 [15] shall be this mandatory format (a MUST
implement for all PIDF implementations supporting the 'geopriv' element).

PIDF-LO serves as a document for the representation of Location Information (LI). This LI identifies the spatial location of a Target; the Target being a generic entity that is likely to be either a person or a Device. LI is a component of the Target's presence information.

The LI that forms the core of a PIDF-LO document originates in the Location Generator (LG). Depending on the specific circumstances, particularly the type of access network, the LG can use any number of methods to determine LI. The range of technologies available for determining LI are numerous and range from user-provided LI, to automatic methods such as wire mapping, radio timing, and GPS.

PIDF-LO is designed to be consumed in a wide range of applications. In some cases the information is presented to a user, maybe in a graphical representation, as a way of identifying the location of the Target. Other applications use LI as input to assist in providing a service.

RFC 4119 can be found at: http://www.ietf.org/rfc/rfc4119.txt
The OGC GeoShape Best Practices document is located at: http://portal.opengeospatial.org/files/?artifact_id=17591