Where ICT offering voice connects to other voice ICT, its documentation must state the main specifications by which RTT interoperates with the ICT it reaches for voice, using either a mutually agreed set meeting the RTT requirements or ITU-T T.140 with IETF RFC 4103 as updated by RFC 9071 (the fallback when nothing else is agreed). Notes survey IMS (TS 126 114), GSMA IR.92 and NG.114, WebRTC data channels (RFC 8831), emergency interfaces (TS 103 479, EN 303 919) and relay (ES 202 975), and explain why analogue text telephony is not a working substitute.
This control maps to 1 controls across 1 other frameworks. If you already hold one of them, the evidence you collected for it is the starting point here rather than new work.
Every mapping shown was judged rather than inferred from wording similarity, and the ones that failed review are published too. See the coverage reports and what was rejected.
The graph holds this control, the 1 it maps to, and the evidence behind each claim, over MCP and REST.