[asterisk-bugs] [Asterisk 0016025]: [patch] failed to negiotate t38

[Asterisk Bug Tracker]

A NOTE has been added to this issue. 
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https://issues.asterisk.org/view.php?id=16025 
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Reported By:                jamicque
Assigned To:                kpfleming
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Project:                    Asterisk
Issue ID:                   16025
Category:                   Channels/chan_sip/T.38
Reproducibility:            always
Severity:                   crash
Priority:                   normal
Status:                     closed
Asterisk Version:           1.6.0.15 
JIRA:                        
Regression:                 No 
Reviewboard Link:            
SVN Branch (only for SVN checkouts, not tarball releases): N/A 
SVN Revision (number only!):  
Request Review:              
Resolution:                 fixed
Fixed in Version:           
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Date Submitted:             2009-10-06 10:16 CDT
Last Modified:              2009-10-12 10:34 CDT
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Summary:                    [patch] failed to negiotate t38
Description: 
I found a problem today, after upgrading from 1.4.x to 1.6.0.15.
When I try to send fax using t38 with ZOIPER softphone thru asterisk to mu
VoIP operator, asterisk fails to negotiate T38.

I found that after the ZOIPER send reinvite with t38, asterisk sends this
reinvite to operator. And then Asterisk send reinvite to operator with g711
??


The asterisk LOG and cap file is in attachment.
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 (0112212) svnbot (reporter) - 2009-10-12 10:34
 https://issues.asterisk.org/view.php?id=16025#c112212 
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Repository: asterisk
Revision: 223692

U   branches/1.4/channels/chan_sip.c

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r223692 | kpfleming | 2009-10-12 10:34:23 -0500 (Mon, 12 Oct 2009) | 13
lines

Remove automatic switching from T.38 to voice mode in chan_sip.
  
chan_sip has some code to automatically switch from T.38 mode to voice
mode when
a voice frame is written to the channel while it is in T.38 mode; this was
intended to handle the situation when a FAX transmission has ended and the
channel
is not yet hung up, but is causing problems at the beginning of FAX
sessions as
well when there are still voice frames 'in flight' at the time the T.38
negotiation
completes. This patch removes the automatic switchover.
  
(issue https://issues.asterisk.org/view.php?id=16025)
Reported by: jamicque


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http://svn.digium.com/view/asterisk?view=rev&revision=223692 

Issue History 
Date Modified    Username       Field                    Change               
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2009-10-12 10:34 svnbot         Checkin                                      
2009-10-12 10:34 svnbot         Note Added: 0112212                          
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