[asterisk-bugs] [Asterisk 0015586]: [patch] Failure to negotiate T.38

[Asterisk Bug Tracker]

A NOTE has been added to this issue. 
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https://issues.asterisk.org/view.php?id=15586 
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Reported By:                globalnetinc
Assigned To:                kpfleming
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Project:                    Asterisk
Issue ID:                   15586
Category:                   Channels/chan_sip/T.38
Reproducibility:            always
Severity:                   major
Priority:                   normal
Status:                     assigned
Asterisk Version:           SVN 
JIRA:                        
Regression:                 No 
SVN Branch (only for SVN checkouts, not tarball releases): N/A 
SVN Revision (number only!):  
Request Review:              
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Date Submitted:             2009-07-26 15:57 CDT
Last Modified:              2009-10-02 07:46 CDT
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Summary:                    [patch] Failure to negotiate T.38
Description: 
To implement T.38 on most ATAs their is a reinvite required.  In the
process of gatewaying the T.38 negotiations the Asterisk server is not
doing this correctly.  On versions past 1.6.0.10 it does not even send the
same ports on the RTP streams to both parties.  

Every version past 1.6.0.10 fails
1.6.0.11
1.6.1.0
1.6.1.1
1.6.2.0-rc

This also includes the new T.38 stack that is is being introduced. in the
SVN tree of 1.6.1.1 and 1.6.2.0
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Relationships       ID      Summary
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has duplicate       0015886 T38 udptl.c bufferoverflow
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 (0111792) kpfleming (administrator) - 2009-10-02 07:46
 https://issues.asterisk.org/view.php?id=15586#c111792 
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You did not include any information as to how you changed your
configuration to take advantage of the override ability provided by the
patch, so I don't really have any way to understand why (or how) your
failure occurred.

In spite of that, I've verified that the patch does in fact allow the
problem to be solved, by connecting Asterisk to another system that reports
'72' for T38FaxMaxDatagram, reproducing the buffer overflow/data loss
errors, and then setting 't38pt_udptl=yes,maxdatagram=400' for that peer in
sip.conf. When that is done, the FAX goes through perfectly. I'm going to
commit the patch to trunk and the 1.6 branches now. 

Issue History 
Date Modified    Username       Field                    Change               
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2009-10-02 07:46 kpfleming      Note Added: 0111792                          
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