LO (Location Object)

In an emergency calling environment, the LO 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 RFCs 5139, 5491 and 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