ATIS 0500012

This ATIS Technical Report is not intended to be seen as an American National Standard (ANS). Rather it is intended to be used as input to further decision-making processes leading to any necessary policy and/or American National Standard formulation. It will be used as a vehicle for communicating location acquisition concepts in liaisons with other relevant Standards Development Organizations (SDOs). This document describes the specific areas of location acquisition in Internet Protocol (IP) access networks. It concerns itself with both the architectures and protocols for supporting these functions. In brief, this is about the manner in which IP devices such as Voice over Internet Protocol (VoIP) clients obtain location information from an access network ¿ location acquisition. For emergency services to work as envisioned by the National Emergency Number Association (NENA) defined i2 architecture for VoIP, location must be available to route the call to a PSAP and to provide the call taker with the caller's location. This information is required in the NENA i2 architecture and will continue to be required in the NENA i3 architecture. This document starts by describing the mechanisms by which a client might obtain location or by which a network might provide location to or on behalf of a client. There are a number of location acquisition protocols which might be used, including DHCP, LLDP-MED, LREP-SIP, HELD, RELO, and LCP. This document provides a targeted analysis of each, but it does not presume that any single protocol will be used universally.