(registered via RFC 7655)

Type name: audio

Subtype name: G711-0

Required parameters:

   clock rate: The RTP timestamp clock rate, which is equal to the
   sampling rate.  The typical rate used with G.711 encoding is 8000,
   but other rates may be specified.  The default rate is 8000.

   complaw: This format-specific parameter, specified on the "a=fmtp:
   line", indicates the companding law (A-law or mu-law) employed.
   This format-specific parameter, as per 
   RFC 8866, is
   given unchanged to the media tool using this format.  The case-
   insensitive values are "complaw=al" or "complaw=mu" are used for
   A-law and mu-law, respectively.

Optional parameters:

   channels: See RFC 8866 for definition.  
   Specifies how
   many audio streams are represented in the G.711.0 payload and MUST
   be present if the number of channels is greater than one.  This
   parameter defaults to 1 if not present (as per 
   RFC8866) and is
   typically a non-zero, small-valued positive integer.  It is
   expected that implementations that specify multiple channels will
   also define a mechanism to map the channels appropriately within
   their system design; otherwise, the channel order specified in 
   Section 4.1 of RFC 3551  will be assumed (e.g., left, right,
   center).  Similar to the usual interpretation in RFC 3551, 
   the number of channels SHALL be a non-zero, positive integer.

   maxptime: See RFC 8866 for definition.

   ptime: See RFC 8866 for definition.  The 
   inclusion of
   "ptime" is RECOMMENDED and SHOULD be in the SDP unless there is an
   application-specific reason not to include it (e.g., an
   application that has a variable ptime on a packet-by-packet
   basis).  For constant ptime applications, it is considered good
   form to include "ptime" in the SDP for session diagnostic
   purposes.  For the constant ptime multiple channel case described
   in Section 4.2.2, the inclusion of "ptime" can provide a desirable
   payload check.

Encoding considerations:

   This media type is framed binary data (see Section 4.8 in RFC 6838) 
   compressed as per ITU-T Rec. G.711.0.

Security considerations:

   See Section 8 of RFC 7655.

Interoperability considerations: none

Published specification:

   ITU-T Rec. G.711.0 and RFC 7655.

Applications that use this media type:

   Although initially conceived for VoIP, the use of G.711.0, like
   G.711 before it, may find use within audio and video streaming
   and/or conferencing applications for the audio portion of those
   applications.

Additional information:

The following applies to stored-file transfer methods:

      Magic numbers: #!G7110A\n or #!G7110M\n (for A-law or MU-law
      encodings respectively, see Section 6).

      File Extensions: None

      Macintosh file type code: None

      Object identifier or OIL: None

Person & email address to contact for further information:

   Michael A.  Ramalho <mramalho&cisco.com> or <mar42&cornell.edu>

Intended usage: COMMON

Restrictions on usage:

   This media type depends on RTP framing, and hence is only defined
   for transfer via RTP [RFC3550].  Transport within other framing
   protocols is not defined at this time.

Author: Michael A.  Ramalho

Change controller:

   IETF Payload working group delegated from the IESG.