[asterisk-bugs] [Asterisk 0013569]: Asterisk sending the wrong codec on re-invite.

[Asterisk Bug Tracker]

A NOTE has been added to this issue. 
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https://issues.asterisk.org/view.php?id=13569 
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Reported By:                bkw918
Assigned To:                dvossel
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Project:                    Asterisk
Issue ID:                   13569
Category:                   Channels/chan_sip/CodecHandling
Reproducibility:            always
Severity:                   minor
Priority:                   normal
Status:                     feedback
Asterisk Version:           1.6.2.0-beta1 
Regression:                 No 
SVN Branch (only for SVN checkouts, not tarball releases): 1.6.1 
SVN Revision (number only!):  
Request Review:              
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Date Submitted:             2008-09-26 17:48 CDT
Last Modified:              2009-05-14 23:09 CDT
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Summary:                    Asterisk sending the wrong codec on re-invite.
Description: 
FreeSWITCH sends invite out to tf.voipmich.com with PCMU, PCMA, GSM.  The
call is answered and setup using GSM since its listed first in the Answer
we receive from Asterisk.  A re-invite promptly follows offering
GSM,PCMU,PCMA to which we 200 OK with ONLY GSM in the SDP in our 200 OK.  

Promptly there after Asterisk starts sending PCMU packets.  The re-invite
is considered a new Session Offer Answer and Asterisk ignores the Answer
and sends a media format not in the new Answer.  

Asterisk PBX SVN-branch-1.6.0-r140976-/trunk is what I can see in the SDP
from John's equipment.  He has disabled re-invites pending a fix for this.

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 (0104797) bkw918 (reporter) - 2009-05-14 23:09
 https://issues.asterisk.org/view.php?id=13569#c104797 
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The information is already in the pcap file attached to this bug its the
exact info I could collect if I worked with John.  All you have to do is
get two Asterisk boxes ready for me to send a call to from FreeSWITCH to
reproduce the problem.  The issue has been described more than once in this
bug report. 

The issue is clear that asterisk doesn't consider the reinvite a new SOA
and uses the codecs from the original invite on the re-invite when our
answer to the reinvite only contains GSM then asterisk promptly starts
sending ulaw when we said in our answer we only want GSM.  It should be
listening to the answer we give them and not taking the codecs from the
original invite into account.

RFC3264 - Section 8.3.2

/b 

Issue History 
Date Modified    Username       Field                    Change               
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2009-05-14 23:09 bkw918         Note Added: 0104797                          
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