[asterisk-bugs] [Asterisk 0015770]: [patch] faxing with T.38 fails

[Asterisk Bug Tracker]

A NOTE has been added to this issue. 
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https://issues.asterisk.org/view.php?id=15770 
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Reported By:                Had
Assigned To:                kpfleming
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Project:                    Asterisk
Issue ID:                   15770
Category:                   Channels/chan_sip/T.38
Reproducibility:            always
Severity:                   major
Priority:                   normal
Status:                     feedback
Asterisk Version:           1.4.26.1 
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:             2009-08-24 12:10 CDT
Last Modified:              2009-08-27 11:03 CDT
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Summary:                    [patch] faxing with T.38 fails
Description: 
I have asterisk 1.4.26.1 setup with T.38 passthrough. I have linksys 2102
ATA and my provider use Cisco gateway with T.38 support enabled. Everytime
I send fax this fail with no apparent reason. 
In sip debug logs it looks that T.38 negotiation was successfull, later I
receive SIP BYE packet from provider and the call si hangup but no fax is
sent.
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 (0109738) kpfleming (administrator) - 2009-08-27 11:03
 https://issues.asterisk.org/view.php?id=15770#c109738 
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Alright, the first thing that I notice in the log and packet capture (and
this was present in your last two or three as well) is that the SIP packets
being received by Asterisk are duplicated... it receives the same SIP
packet from the ATA or your provider two, three or four times. This is
indicative of some sort of very strange network problem, and if it is
happening to the media packets as well, there's no way that T.38 is going
to work properly (and audio calls are going to sound strange as well).

I do see one problem happening here because of the repeated SIP messages,
which I'll try to address, but you really need to figure out what is
causing that problem, because fixing it will probably solve your T.38
issues as well. 

Issue History 
Date Modified    Username       Field                    Change               
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2009-08-27 11:03 kpfleming      Note Added: 0109738                          
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