Search RFCs

RFC Editor

File formats:

Status:

PROPOSED STANDARD

Obsoletes:

RFC 2833

Updated by:

RFC 4734,RFC 5244

Authors:

H. Schulzrinne
T. Taylor

Stream:

IETF

Source:

avt (rai)

Cite this RFC:TXT  | XML  |  BibTeX

DOI:  https://doi.org/10.17487/RFC4733

Discuss this RFC: Send questions or comments to the mailing listavt@ietf.org

Other actions:View Errata  | Submit Errata  | Find IPR Disclosures from the IETF  | View History of RFC 4733

Abstract

This memo describes how to carry dual-tone multifrequency (DTMF)signalling, other tone signals, and telephony events in RTP packets.It obsoletes RFC 2833.

This memo captures and expands upon the basic framework defined inRFC 2833, but retains only the most basic event codes. It sets up anIANA registry to which other event code assignments may be added.Companion documents add event codes to this registry relating tomodem, fax, text telephony, and channel-associated signalling events.The remainder of the event codes defined in RFC 2833 areconditionally reserved in case other documents revive their use.

This document provides a number ofclarifications to the original document. However, it specificallydiffers from RFC 2833 by removing the requirement that all compliantimplementations support the DTMF events. Instead, compliantimplementations taking part in out-of-band negotiations of mediastream content indicate what events they support. This memoadds three new procedures to the RFC 2833 framework: subdivision oflong events into segments, reporting of multiple events in a singlepacket, and the concept and reporting of state events. [STANDARDS-TRACK]

For the definition ofStatus,seeRFC 2026.

For the definition ofStream, seeRFC 8729.