[asterisk-bugs] [Asterisk 0015610]: T.38 re-INVITE received after T.38 already negotiated fails

[Asterisk Bug Tracker]

A NOTE has been added to this issue. 
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https://issues.asterisk.org/view.php?id=15610 
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Reported By:                huangtx2009
Assigned To:                
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Project:                    Asterisk
Issue ID:                   15610
Category:                   Applications/app_fax
Reproducibility:            sometimes
Severity:                   minor
Priority:                   normal
Status:                     new
Asterisk Version:           1.6.1-beta4 
Regression:                 No 
SVN Branch (only for SVN checkouts, not tarball releases): 1.6.1 
SVN Revision (number only!): 209327 
Request Review:              
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Date Submitted:             2009-07-29 16:16 CDT
Last Modified:              2009-08-06 12:47 CDT
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Summary:                    T.38 re-INVITE received after T.38 already
negotiated fails
Description: 
I used the latest asterisk1.6.1 and spandsp0.0.6pre12. I tried to send Fax
to a Fax service provider supporting SIP T.38 (They claim their Fax service
can work with many devices well).

It is seldom successful.

But it often fails. Moreover, the error is different.
Sometimes, the error is "Unexpected message received".
Sometimes, the asterisk sender responds with 488 Not acceptable here to
the Re-INVITE for T.38.
Sometimes, the error is "the HDLC carrier did not stop in a timely
manner".

I wonder it is buggy or I do not configure something correctly. Thanks a
lot.


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 (0108726) svnbot (reporter) - 2009-08-06 12:47
 https://issues.asterisk.org/view.php?id=15610#c108726 
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Repository: asterisk
Revision: 210817

U   trunk/channels/chan_sip.c

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r210817 | file | 2009-08-06 12:47:23 -0500 (Thu, 06 Aug 2009) | 11 lines

Accept additional T.38 reinvites after an initial one has been handled.

Discussion of this subject has yielded that it is not actually acceptable
to change
T.38 parameters after the initial reinvite but declining is harsh and can
cause the
fax to fail when it may be possible to allow it to continue. This patch
changes things
so that additional T.38 reinvites are accepted but parameter changes
ignored. This gives
the fax a fighting chance.

(closes issue https://issues.asterisk.org/view.php?id=15610)
Reported by: huangtx2009

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http://svn.digium.com/view/asterisk?view=rev&revision=210817 

Issue History 
Date Modified    Username       Field                    Change               
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2009-08-06 12:47 svnbot         Checkin                                      
2009-08-06 12:47 svnbot         Note Added: 0108726                          
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