LOC record

In the Domain Name System, a LOC record (experimental ) is a means for expressing geographic location information for a domain name.

It contains WGS84 Latitude, Longitude and Altitude (ellipsoidal height) information together with host/subnet physical size and location accuracy. This information can be queried by other computers connected to the Internet.

Record format

The LOC record is expressed in a master file in the following format:

LOC ( d1 [m1 [s1]] {"N"|"S"} d2 [m2 [s2]] {"E"|"W"} alt["m"] [siz["m"] [hp["m"] [vp["m"]]]] )

(The parentheses are used for multi-line data as specified in RFC 1035, section 5.1.)

where:

<pre> d1: [0 .. 90] (degrees latitude) d2: [0 .. 180] (degrees longitude) m1, m2: [0 .. 59] (minutes latitude/longitude) s1, s2: [0 .. 59.999] (seconds latitude/longitude) alt: [-100000.00 .. 42849672.95] BY .01 (altitude in meters) siz, hp, vp: [0 .. 90000000.00] (size/precision in meters) </pre>

An example DNS LOC resource record

• statdns.net for the coordinates:

Altitude for Geosynchronous Earth Satellites

The altitude range provides the following:

• DNS altitude range [-100000.00 .. 42849672.95]. This range can be easily stored in 4 bytes.
• Maximum altitude is 42,849.67295&nbsp;km. Which is large enough to store the altitude of a circular geosynchronous orbit (i.e. approximately 35,790&nbsp;km above mean sea level).
• Maximum depth of 100&nbsp;km below earth surface (approximated by the WGS84 reference ellipsoid).

See also

• List of DNS record types
• Geo (microformat)
• Geolocation
• Geolocation API
• ICBM address
• ISO 6709

References

• The Wikipedia location resource.
• Sites supporting DNS LOC
• - How latitude and longitude are stored in a DNS record.
• Chapter 3.4.2: Text/directory MIME type GEO
• Section 6.5.2: GEO (obsoleted , updated by )