[asterisk-bugs] [Asterisk 0011376]: Codec negotiation results in asterisk sending unsupported codec

[noreply at bugs.digium.com]

A NOTE has been added to this issue. 
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http://bugs.digium.com/view.php?id=11376 
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Reported By:                lasse
Assigned To:                
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Project:                    Asterisk
Issue ID:                   11376
Category:                   Channels/chan_sip/CodecHandling
Reproducibility:            always
Severity:                   minor
Priority:                   normal
Status:                     feedback
Asterisk Version:           1.4.14  
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:             11-26-2007 07:51 CST
Last Modified:              11-27-2007 01:22 CST
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Summary:                    Codec negotiation results in asterisk sending
unsupported codec
Description: 
SIP Phone client that  supports only iLBC
Asterisk configured to support alaw, ilbc in that order (sip.conf).
PSTN provider supports all kinds of codecs

Call from PSTN to sip phone works fine (PSTN -> alaw -> Asterisk -> ilbc
-> SIP client)

BUT if the order of the codecs in sip.conf is ilbc, alaw asterisk will
send ilbc to PSTN provider and alaw to SIP client (allthough it indicates
it only support ilbc in SDP) resulting in a failed call.
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---------------------------------------------------------------------- 
 oej - 11-27-07 01:22  
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Well, they do offer ALAW and we answer with ILBC and ALAW, so they can send
ALAW to us, but decide not to do it.  This seems to be a bug in both ends.

According to the latest discussions in the SIP standards groups, we should
not offer ILBC in the answer. But that's no reason for them cancelling the
call when we answer that we would prefer ILBC, but still accept ALAW. 

Issue History 
Date Modified   Username       Field                    Change               
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11-27-07 01:22  oej            Note Added: 0074386                          
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