[asterisk-bugs] [Asterisk 0011483]: Asterisk rejects legitimate G.729a call with 488 Not Acceptable Here

[noreply at bugs.digium.com]

A NOTE has been added to this issue. 
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http://bugs.digium.com/view.php?id=11483 
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Reported By:                revolution
Assigned To:                
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Project:                    Asterisk
Issue ID:                   11483
Category:                   Core/RTP
Reproducibility:            always
Severity:                   minor
Priority:                   normal
Status:                     new
Asterisk Version:           1.4.15  
SVN Branch (only for SVN checkouts, not tarball releases): N/A  
SVN Revision (number only!):  
Disclaimer on File?:        N/A 
Request Review:              
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Date Submitted:             12-06-2007 09:33 CST
Last Modified:              12-07-2007 04:05 CST
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Summary:                    Asterisk rejects legitimate G.729a call with 488 Not
Acceptable Here
Description: 
Linksys/Sipura brand phones send rtpmap:18 as G729a (other brands may as
well). Although technically legitimate and correct, INVITE is being
rejected with 488 Not acceptable here -- i.e. no compatible codecs despite
the fact that realtime sip peer is set to allow g729.

After going into Linksys/Sipura SPA-941 (as well as SPA-2100) and altering
name of rtpmap:18 to G729 (sans the a) -- call was accepted and completed
as expected.

Attaching two capture files (for the rejected call and the accepted call)
as well as a patch to rtp.c which seems to fix this minor issue (mostly
just an annoyance).
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---------------------------------------------------------------------- 
 oej - 12-07-07 04:05  
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http://www.iana.org/assignments/rtp-parameters

There's no definition of a label "G729a". Linksys has a bug in their
software.

RFC4856 defines the following headers:
      audio/G729
      audio/G729D
      audio/G729E

And I can't find any documented use of "audio/G729a".

Also see
*
https://lists.cs.columbia.edu/pipermail/sip-implementors/2006-July/013659.html

Anyway, let's implement it as an alias if it breaks communication. 

Issue History 
Date Modified   Username       Field                    Change               
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12-07-07 04:05  oej            Note Added: 0075011                          
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