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Real-Time Transport Protocol (RTP) Payload for Text Conversation Interleaved in an Audio Stream

Approval announcement
Draft of message to be sent after approval:


From: The IESG <>
To: IETF-Announce <>
Cc: Internet Architecture Board <>,
    RFC Editor <>, 
    avt mailing list <>, 
    avt chair <>
Subject: Protocol Action: 'RTP Payload for Text Conversation 
         interleaved in an audio stream' to Historic 

The IESG has approved the following document:

- 'RTP Payload for Text Conversation interleaved in an audio stream '
   <draft-ietf-avt-audio-t140c-01.txt> as a Historic

This document is the product of the Audio/Video Transport Working Group. 

The IESG contact persons are Allison Mankin and Jon Peterson.

A URL of this Internet-Draft is:

Ballot Text

Technical Summary
   The audio/t140c payload specification is intended to allow gateways 
   interconnecting two PSTN networks to interleave, through a 
   single RTP session, audio and text data received on the PSTN 
   circuit.    The T.140 text data is interleaved with audio codec data
   using the same UDP port, but this can only be done (in the
   design preserved by this specification) if there is a shared top-level
   type to the registered media type.  The same issue affected the
   audio/clearmode media type for the PSTN applications in RFC 4040,
   but in that case the interleaved streams were both more like audio.

   Like RFC 4040, this specification offers a secure, well-engineered
   payload and media registration for a specific, PSTN application
   that needs support.  This specification will not apply beyond that
   application, in strong contrast to RFC 4103, which registred text/t140,
   and offered an open field for uses.  The present specification states
   normatively that it must be have no further applications beyond the
   PSTN gateway applications.

Working Group Summary

  There was a lengthy discussion of this material.  It was originally
  included in the document that became RFC 4103 and was
  split out to progress independently.  There was consensus for the
  work to be published.

  In order not to set further precedent for using the audio
  top level type for non-audio data, but in order to allow the
  usage which is needed and deployed to be registered, the document was 
  Last Called as a Historic document.  The editor and the IESG discussed
  the designation, but there were no further community comments on this.

Protocol Quality
 This protocol is implemented in products.  The specification
 represents engineering and security review by the AVT working
 group of significant standards and deployment past efforts by
 the ITU-T Study Group 16.

Notes to RFC Editor

 Section 10.1

Change controller:

Change controller:
IETF avt WG delegated from the IESG

RFC Editor Note