[asterisk-bugs] [Asterisk 0016221]: T.38 passthrough issue in 1.6.1.6

[Asterisk Bug Tracker]

The following issue requires your FEEDBACK. 
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https://issues.asterisk.org/view.php?id=16221 
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Reported By:                zalex1953
Assigned To:                kpfleming
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Project:                    Asterisk
Issue ID:                   16221
Category:                   Channels/chan_sip/T.38
Reproducibility:            always
Severity:                   major
Priority:                   normal
Status:                     feedback
Asterisk Version:           Older 1.6.1 
JIRA:                        
Regression:                 No 
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:             2009-11-10 17:51 CST
Last Modified:              2009-11-16 09:03 CST
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Summary:                    T.38 passthrough issue in 1.6.1.6
Description: 
I'd select Category Core/udptl if it was in a drop-down list
I'd also select Product version 1.6.1.6 (also not in the list)

Asterisk server is in between 'fax server' (64.108.238.147) and 'provider'
(72.35.229.246 for signaling, .236 for RTP and .238 for udptl). Asterisk
server communicates via 208.64.102.75 with provider and via .77 with fax
server.

Asterisk server is supposed to work in T.38 pass-through mode.

.pcap file should be attached. It contains 2 fax sessions, sending the
same fax from fax server to provider. Session 1 is for FFA based fax
server, there are no issues. Session 2 is for Dialogic SR140 based fax
server, session fails consistently. 

In both sessions SIP negotiation with T.38 re-INVITE and start of T.30 is
fine. Provider sends DIS, fax server replies with '66 TSI' and '65 DCS'.
The issue is with training. Session 1 training info goes through asterisk
server OK and provider sends '33, RTP'. Session 2 training info gets stuck
within asterisk server, provider repeats DIS, fax server re-sends TSI and
DCS and training fails again.

Please, look at packets 732-822 (session 1), they go through. Packets
2228-2390 (session 2) don't go through. Packet 2369 (seq. 8) is the only
one that makes it, seq. 9-25 are gotten from a fax server but are not sent
to provider.

Thank you.

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 (0113848) file (administrator) - 2009-11-16 09:03
 https://issues.asterisk.org/view.php?id=16221#c113848 
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Please retest this using the latest version. There have been substantial
changes to the way that fax works and is communicated through the core. If
the problem still exists then a new pcap and an Asterisk log would be
needed. 

Issue History 
Date Modified    Username       Field                    Change               
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2009-11-16 09:03 file           Note Added: 0113848                          
2009-11-16 09:03 file           Status                   assigned => feedback
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