[asterisk-bugs] [Asterisk 0018431]: 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=18431 
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Reported By:                globalnetinc
Assigned To:                
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Project:                    Asterisk
Issue ID:                   18431
Category:                   Channels/chan_sip/T.38
Reproducibility:            always
Severity:                   major
Priority:                   normal
Status:                     acknowledged
Asterisk Version:           SVN 
JIRA:                        
Regression:                 No 
Reviewboard Link:            
SVN Branch (only for SVN checkouts, not tarball releases): 1.8 
SVN Revision (number only!): 297607 
Request Review:              
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Date Submitted:             2010-12-06 21:43 CST
Last Modified:              2010-12-07 22:41 CST
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Summary:                    Regression - T.38 no longer functions
Description: 
Fax calls fail.  Modems never acan complete the trin.

maxdatagram is ignored

t38pt_udptl=yes,redundancy,maxdatagram=200

is set in the sip.conf file the peers

this is the invite from the ATA
INVITE sip:8884732963 at 172.16.0.4:5060 SIP/2.0
Via: SIP/2.0/UDP 192.168.255.2:5060;branch=z9hG4bK-5e239d89;rport
From: The Johnson Company
<sip:4065877430 at 172.16.0.4>;tag=dc054a6d8968ca5bo1
To: <sip:8884732963 at 172.16.0.4>;tag=as78c8bd8c
Remote-Party-ID: The Johnson Company
<sip:4065877430 at 172.16.0.4>;screen=yes;party=calling
Call-ID: 5f8ff155-63701093 at 192.168.255.2
CSeq: 103 INVITE
Max-Forwards: 70
Authorization: Digest
username="4065877430",realm="asterisk",nonce="2a864f78",uri="sip:8884732963 at 172.16.0.4:5060",algorithm=MD5,response="68727e467a7265f353f4528567397463"
Contact: The Johnson Company <sip:4065877430 at 172.16.0.59:5060>
Expires: 30
User-Agent: Linksys/SPA2102-5.2.10
Content-Length: 265
Content-Type: application/sdp

v=0
o=- 2664756 2664756 IN IP4 172.16.0.59
s=-
c=IN IP4 172.16.0.59
t=0 0
m=image 16446 udptl t38
a=T38FaxVersion:0
a=T38MaxBitRate:14400
a=T38FaxRateManagement:transferredTCF
a=T38FaxMaxBuffer:200
a=T38FaxMaxDatagram:200
a=T38FaxUdpEC:t38UDPRedundancy


Here is what comes out of Asterisk to the trunk provider

INVITE sip:18884732963 at 66.62.196.101:5060;transport=udp SIP/2.0
Via: SIP/2.0/UDP 216.166.168.4:5060;branch=z9hG4bK2ba7f248
Max-Forwards: 70
From: "The Johnson Company" <sip:4065877430 at 216.166.168.4>;tag=as1474ad27
To: <sip:18884732963 at 66.62.196.101>;tag=f51b80c154cc3e34cc79c473e7e19ed1
Contact: <sip:4065877430 at 216.166.168.4:5060>
Call-ID: 2119ea362e8f33da1e22c71623993b59 at 216.166.168.4:5060
CSeq: 103 INVITE
User-Agent: Asterisk PBX
Require: timer
Session-Expires: 1800;refresher=uac
Min-SE: 90
Allow: INVITE, ACK, CANCEL, OPTIONS, BYE, REFER, SUBSCRIBE, NOTIFY, INFO,
PUBLISH
Supported: replaces, timer
X-asterisk-Info: SIP re-invite (External RTP bridge)
Remote-Party-ID: "The Johnson Company"
<sip:4065877430 at 216.166.168.4>;party=calling;privacy=off;screen=no
Content-Type: application/sdp
Content-Length: 266

v=0
o=root 1572151211 1572151212 IN IP4 216.166.168.4
s=Asterisk PBX
c=IN IP4 216.166.168.4
t=0 0
m=image 14370 udptl t38
a=T38FaxVersion:0
a=T38MaxBitRate:14400
a=T38FaxRateManagement:transferredTCF
a=T38FaxMaxDatagram:788
a=T38FaxUdpEC:t38UDPRedundancy

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---------------------------------------------------------------------- 
 (0129456) globalnetinc (reporter) - 2010-12-07 22:41
 https://issues.asterisk.org/view.php?id=18431#c129456 
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Try again to describe it. This time not late at night so I can truely type.
 Modems go through the entire process trying to train on a baud rate then
give up.  Also the maxdatagram is ignored.  This has run in the past with
pre 1.8.0 release and 1.6.2.9. 

Issue History 
Date Modified    Username       Field                    Change               
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2010-12-07 22:41 globalnetinc   Note Added: 0129456                          
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