scope:

The scope of this Standard is to specify a base level of Mobile Device Behavior for supporting Real Time Text (RTT) capabilities when accessing Voice over Long Term Evolution (VoLTE) networks¹. The Standard includes the minimum behavior of the mobile device needed for performing RTT user-to-user communication within and between VoLTE Commercial Mobile Service Providers (CMSPs).

The scope of this Standard covers RTT implementations, as specified in IETF RFC 4103 [Ref 5] and as described in ATIS-1000068 [Ref 1] and ATIS-0700030 [Ref 6], for both emergency and non-emergency communications via CMSP networks.

The mobile devices that support real time text capabilities as defined in this standard are referred to as RTTcapable mobile devices.

Purpose

The purpose of this Standard is to specify certain aspects of mobile device behavior to facilitate RTT conversations between mobile devices across CMSPs.

¹ The support of RTT over Wi-Fi is for further study.