ISO/TS 21219-21:2018 defines a method of using geographic location referencing (GLR) that can be used by relevant TPEG applications. The GLR type is defined in this document. It is used for defining geographic location references (points, polylines, and geographical areas). The GLR method is intended to be one of the methods that can be transported inside a TPEG-location referencing container (TPEG-LRC) for those TPEG applications providing information for primarily geographical locations (e.g. weather).
The GLR specification is kept basic and compact on purpose, such that it can also be employed advantageously in non-navigation devices for simple TPEG services such as weather information, safety alerts, etc. As such, the GLR location referencing method is intended to be complementary to map-related location referencing methods, where the focus rather is on the referencing of man-made artefacts such as roads and highways.
The scope of GLR is limited to geographic locations on the Earth's surface for the above-mentioned rationale.