LO (Location Object)

In an emergency calling environment, the LO (Location Object) is used to refer to the current position of an endpoint that originates an emergency call. The LO is expected to be formatted as a Presence Information Data Format – Location Object (PIDF-LO) as defined by the IETF in RFC 4119, updated by RFC 5139, RFC 5491, RFC 7459, and extended by RFC 6848.

The LO may be:
 * Geodetic – shape, latitude(s), longitude(s), elevation, uncertainty, confidence and the datum which identifies the coordinate system used. NENA prescribes that geodetic location information will be formatted using the World Geodetic System 1984 (WGS 84) datum;
 * Civic location – a set of elements describing detailed street address information. For NG9-1-1 in the U.S., the civic LO must conform to NENA Next Generation 9-1-1 (NG9-1-1) United States Civic Location Data Exchange Format (CLDXF) Standard (NENA-STA-004);
 * Or a combination thereof.


 * NENA-STA-010, Detailed Functional and Interface Standards for the NENA i3 Solution
 * NENA 08-505, NENA Recommended Method(s) for Location Determination to Support IP-Based Emergency Services - Technical Information Document (TID)