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RFC 5870 / GEOGRAPHIC LOCATION LINKS

From a link to coordinates

01

A geo URI identifies a physical location. A supporting application extracts coordinates; it chooses what to do with them.

DIAGRAMRead RFC section 5 ↗
RFC 5870 · § 5EXAMPLE
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From a link to coordinatesThe public location URI geo13.4125 comma103.8667 first appears as an identifier with no host or network request. The next state separates latitude13.4125 north from longitude103.8667 east on a schematic angular grid whose axes are explicitly labelled; URI order is latitude then longitude even though the horizontal axis is longitude. Last a location application receives extracted coordinates and offers an optional map use. Extraction is the defined dereference operation, not an obligatory HTTP transaction or a guaranteed installed handler.A physical location, independent of a map serviceLocation URILocation applicationextract coordinatesLatitude: 13.4125°Longitude: 103.8667°optional map useApplication choice, not a required network fetch
03
Let the application choose a use.

A supporting application extracts the same coordinates. It might offer a map or navigation, but the RFC does not require a particular service or guarantee a working installed handler.

Source for this drawing: RFC 5870 · Read RFC section 5 ↗

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A message needs an address.

Think of a packet as a small addressed envelope. Devices pass it onward; transport protocols decide what delivery promises an application gets.

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RFC 3986 URI syntax

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Terms in this drawing
URI
Uniform Resource Identifier: a compact identifier; a geo URI identifies a physical location rather than a web page.
WGS-84
World Geodetic System 1984, the default coordinate reference system (CRS) used to interpret these numbers.
Decimal degrees
Angles written as signed decimal numbers, rather than degrees, minutes and seconds.
Related RFCs and changes

“Updates” changes part of an earlier RFC. “Obsoletes” replaces it. This list shows selected related documents.

KEY POINT

Read latitude first, longitude second, in decimal degrees.

  • In the default WGS-84 coordinate reference system, latitude MUST be first and longitude second, each in decimal degrees. A comma separates them; it MUST NOT be percent-encoded.
  • The optional third coordinate is altitude. Parameters follow semicolons, not a query string. Coordinate digits have no leading plus, exponent or locale decimal comma under §3.3.
  • Dereferencing means extracting the location, not performing an HTTP request to a host. Mapping, navigation and nearby searches are non-normative application choices.
DETAILS

The public example geo:13.4125,103.8667 comes from §1. The plot is a schematic latitude/longitude grid, not a projected map. This guide does not invoke a location handler, fetch a map or track a person.

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