This TS defines the stage one description of the Global Text Telephone Feature, GTT. Stage one is the set of requirements which shall be supported for the provision of the real-time text conversation feature, seen primarily from the subscriber's and service providers' points of view.
This TS defines the requirements for GTT to be understood as a framework to enable real-time transmission of text, for the purpose of a text based or text supported conversation between users. Text may be transported alone or in combination with other media in the session, especially video and voice.
Thus the GTT enables text conversation to be included in any mobile conversational service.
Interworking with existing text telephony in PSTN as well as emerging forms of standardised text conversation in all networks is within the scope of this TS. Interoperation with Multimedia Messaging Services is also within scope of this feature.
Note: The Global Text Telephony feature may be enhanced due to e.g. operator's or regulator's requirements, however such additional functionality shall not compromise conformance to the core requirements documented in this TS.