[asterisk-bugs] [Asterisk 0016497]: [regression] T.38 no longer functions

[Asterisk Bug Tracker]

A NOTE has been added to this issue. 
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https://issues.asterisk.org/view.php?id=16497 
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Reported By:                globalnetinc
Assigned To:                mnicholson
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Project:                    Asterisk
Issue ID:                   16497
Category:                   Channels/chan_sip/T.38
Reproducibility:            always
Severity:                   major
Priority:                   normal
Status:                     assigned
Target Version:             1.6.1.14
Asterisk Version:           1.6.1.12 
JIRA:                       SWP-603 
Regression:                 Yes 
Reviewboard Link:            
SVN Branch (only for SVN checkouts, not tarball releases): N/A 
SVN Revision (number only!):  
Request Review:              
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Date Submitted:             2009-12-21 19:59 CST
Last Modified:              2010-01-11 11:47 CST
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Summary:                    [regression] T.38 no longer functions
Description: 
After upgrade from 1.6.11 to 1.6.1.12 T.38 no longer functions.

WARNING[26670] udptl.c: (SIP/4065877430): UDPTL asked to send 1 bytes of
IFP when far end only prepared to accept 0 bytes; data loss will occur.You
may need to override the T38FaxMaxDatagram value for this endpoint in the
channel driver configuration.

This is generated even though sip.conf has
t38pt_udptl=yes,redundancy,maxdatagram=176

After returning to 1.6.1.11 T.38 functions correctly.
 
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 (0116448) globalnetinc (reporter) - 2010-01-11 11:47
 https://issues.asterisk.org/view.php?id=16497#c116448 
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Please read the info.  

t38pt_udptl=yes,redundancy,maxdatagram=176

yet the error reports UDPTL asked to send 1 bytes of IFP when far end only
prepared to accept 0 bytes; data loss will occur.You may need to override
the T38FaxMaxDatagram value for this endpoint in the channel driver
configuration.

If it was reading the SDP or the the maxdatagram correctly it would have
at least 176 in the value not zero.  If the version is returned to 1.6.1.11
it faxes and does read the value.  Just setting to 400 makes no difference
nor should you be doing it unless both ends can accept that as a packet. 
In my case the largest packet that the SIP provider will accept is 176. 
9600 baud with redundancy and a redundancy value of 1 

Issue History 
Date Modified    Username       Field                    Change               
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2010-01-11 11:47 globalnetinc   Note Added: 0116448                          
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