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RTP Payload for DTMF Digits, Telephony Tones, and Telephony Signals
RFC 4733

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 DTMF Digits, 
         Telephony Tones and Telephony Signals' to Proposed Standard 

The IESG has approved the following documents:

- 'Definition of Events For Modem, FAX, and Text Telephony Signals '
   <draft-ietf-avt-rfc2833bisdata-09.txt> as a Proposed Standard
- 'RTP Payload for DTMF Digits, Telephony Tones and Telephony Signals '
   <draft-ietf-avt-rfc2833bis-16.txt> as a Proposed Standard

These documents are products of the Audio/Video Transport Working Group. 

The IESG contact persons are Cullen Jennings and Jon Peterson.

A URL of this Internet-Draft is:

Ballot Text

Technical Summary

This document defines the RTP Payload format for telephony events over 
RTP and the usage of DTMF in this payload format. It also establish a 
registry in which further telephony events using this payload format may 
be registered in. The document also defines an RTP Payload format for 
tones used in telephony systems. The payload format is capable of 
describing single, multiple or modulated tones.


This document defines 31 additional events to be used with the RTP 
payload format for telephony events defined in 
draft-ietf-avt-rfc2833bis. The defined event cover the usage with a 
number of ITU specifications such as V.8, V.8 bis, V.21, V.25, 
V.32/V.32bis, and T.30.

Working Group Summary:

There is consensus in the WG to publish these documents.

Protocol Quality:

These documents are updates of RFC 2833 which is obsoleted. The 
implementation experience for RFC 2833 has been taken into account in 
these updates. The documents have been reviewed by both IETF and ITU-T 
Study Group 16. The media types were reviewed on ietf-types list in
November 2005.

RFC Editor Note