RTP Payload Format for G.719
RFC 5404

Network Working Group                                      M. Westerlund
Request for Comments: 5404                                  I. Johansson
Category: Standards Track                                    Ericsson AB
                                                            January 2009

                      RTP Payload Format for G.719

Status of This Memo

   This document specifies an Internet standards track protocol for the
   Internet community, and requests discussion and suggestions for
   improvements.  Please refer to the current edition of the "Internet
   Official Protocol Standards" (STD 1) for the standardization state
   and status of this protocol.  Distribution of this memo is unlimited.

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Abstract

   This document specifies the payload format for packetization of the
   G.719 full-band codec encoded audio signals into the Real-time
   Transport Protocol (RTP).  The payload format supports transmission
   of multiple channels, multiple frames per payload, and interleaving.

Westerlund & Johansson      Standards Track                     [Page 1]
RFC 5404              RTP Payload Format for G.719          January 2009

Table of Contents

   1.  Introduction . . . . . . . . . . . . . . . . . . . . . . . . .  3
   2.  Definitions and Conventions  . . . . . . . . . . . . . . . . .  3
   3.  G.719 Description  . . . . . . . . . . . . . . . . . . . . . .  3
   4.  Payload Format Capabilities  . . . . . . . . . . . . . . . . .  4
     4.1.  Multi-Rate Encoding and Rate Adaptation  . . . . . . . . .  4
     4.2.  Support for Multi-Channel Sessions . . . . . . . . . . . .  5
     4.3.  Robustness against Packet Loss . . . . . . . . . . . . . .  5
       4.3.1.  Use of Forward Error Correction (FEC)  . . . . . . . .  5
       4.3.2.  Use of Frame Interleaving  . . . . . . . . . . . . . .  6
   5.  Payload Format . . . . . . . . . . . . . . . . . . . . . . . .  7
     5.1.  RTP Header Usage . . . . . . . . . . . . . . . . . . . . .  8
     5.2.  Payload Structure  . . . . . . . . . . . . . . . . . . . .  8
       5.2.1.  Basic ToC Element  . . . . . . . . . . . . . . . . . .  9
     5.3.  Basic Mode . . . . . . . . . . . . . . . . . . . . . . . . 10
     5.4.  Interleaved Mode . . . . . . . . . . . . . . . . . . . . . 10
     5.5.  Audio Data . . . . . . . . . . . . . . . . . . . . . . . . 11
     5.6.  Implementation Considerations  . . . . . . . . . . . . . . 12
       5.6.1.  Receiving Redundant Frames . . . . . . . . . . . . . . 12
       5.6.2.  Interleaving . . . . . . . . . . . . . . . . . . . . . 12
       5.6.3.  Decoding Validation  . . . . . . . . . . . . . . . . . 13
   6.  Payload Examples . . . . . . . . . . . . . . . . . . . . . . . 13
     6.1.  3 Mono Frames with 2 Different Bitrates  . . . . . . . . . 13
     6.2.  2 Stereo Frame-Blocks of the Same Bitrate  . . . . . . . . 14
     6.3.  4 Mono Frames Interleaved  . . . . . . . . . . . . . . . . 15
   7.  Payload Format Parameters  . . . . . . . . . . . . . . . . . . 16
     7.1.  Media Type Definition  . . . . . . . . . . . . . . . . . . 16
     7.2.  Mapping to SDP . . . . . . . . . . . . . . . . . . . . . . 19
       7.2.1.  Offer/Answer Considerations  . . . . . . . . . . . . . 19
       7.2.2.  Declarative SDP Considerations . . . . . . . . . . . . 22
   8.  IANA Considerations  . . . . . . . . . . . . . . . . . . . . . 23
   9.  Congestion Control . . . . . . . . . . . . . . . . . . . . . . 23
   10. Security Considerations  . . . . . . . . . . . . . . . . . . . 24
   11. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 25
   12. References . . . . . . . . . . . . . . . . . . . . . . . . . . 25
     12.1. Normative References . . . . . . . . . . . . . . . . . . . 25
     12.2. Informative References . . . . . . . . . . . . . . . . . . 26

Westerlund & Johansson      Standards Track                     [Page 2]
RFC 5404              RTP Payload Format for G.719          January 2009

1.  Introduction

   This document specifies the payload format for packetization of the
   G.719 full-band (FB) codec encoded audio signals into the Real-time
   Transport Protocol (RTP) [RFC3550].  The payload format supports
   transmission of multiple channels, multiple frames per payload, and
   packet loss robustness methods using redundancy or interleaving.