[asterisk-bugs] [JIRA] (ASTERISK-27424) PJSIP T.38 Re-Invites fail between 2 extensions running Fax Voip FSP Windows Fax Service Provider

[Richard Mudgett (JIRA)]

    [ https://issues.asterisk.org/jira/browse/ASTERISK-27424?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=240200#comment-240200 ] 

Richard Mudgett commented on ASTERISK-27424:
--------------------------------------------

In the 3.zip log, the sequence fails because the sender (192.168.2.92) is not responding to Asterisk's T.38 reINVITE.

As a note to who looks at the issue:  Asterisk is not sending a 100 Trying in response to the T.38 reINVITE's received for some reason.  Doing this would at least stop the T.38 reINVITE retransmissions while Asterisk waits for a response to the bridged peer.


> PJSIP T.38 Re-Invites fail between 2 extensions running Fax Voip FSP Windows Fax Service Provider
> -------------------------------------------------------------------------------------------------
>
>                 Key: ASTERISK-27424
>                 URL: https://issues.asterisk.org/jira/browse/ASTERISK-27424
>             Project: Asterisk
>          Issue Type: Bug
>      Security Level: None
>          Components: Resources/res_pjsip_session, Resources/res_pjsip_t38
>    Affects Versions: 15.1.0
>         Environment: 1 x Asterisk server
> 2 x Windows 10 workstations, 
>   each workstation has:
>      1. "Windows Fax & Scan" (WFS.exe) 
>      2. Fax Voip FSP Windows Fax Service Provider  (FSP)
>           (note that virtual machines are not recommended by Voip FSP faq).
>           15 Day trial available here: http://www.t38faxvoip.com/fsp/
>      3. Wireshark packet capture software running on both Windows computers.
>     4. Configure an extension in asterisk for each FSP.
> The extensions endpoints in the asterisk pjsip.conf should have the following settings added:
> t38_udptl=yes
> t38_udptl_ec=redundancy
> fax_detect=no
> t38_udptl_nat=yes
> For debug logging ensure that logger.conf has has debug specified eg.:
> console => debug,error,notice,verbose,warning
> full => debug,error,notice,verbose,warning
> $asterisk -r
> freepbx*CLI> core set debug 9
> Core debug was OFF and is now 9.
> freepbx*CLI> pjsip set logger on
> PJSIP Logging enabled
> 1 .Setup SIP extensions in "Fax Voip FSP Windows Fax Service Provider " software.
>    Fax Voip FSP->VOIP->SIP->Registrations
> 2.Check box Fax Voip FSP->VOIP->SIP->T.38 Fax->T.38 Fax reception -> Switch to T.38 on CNG tone received.
> Other scenarios should probably work but this one would be a good starting point.
>            Reporter: Jared Davison
>            Severity: Minor
>         Attachments: 3.zip, 4.zip, T.38 Fax Asterisk Log 2.txt, T.38 Fax Receiver 2.pcapng, T.38 Fax Sender 2.pcapng, T.38 Fax via 3CX.pcapng
>
>
> Sending a T.38 fax between two extensions running the "Fax Voip FSP Windows Fax Service Provider " on the same Asterisk PBX fails.
> My suggestion is to reproduce the scenario of one side sending to the other in order to understand the issues completely, and test any fixes.
> In Windows Fax and Scan create a fax and send it to the extension on the other computer.
> Please see the notes and discussion on the asterisk community forum (see external issue ID) which lead to this case's creation.
> https://community.asterisk.org/t/t-38-fax-passthrough-via-using-pjsip-extensions/72632/3



--
This message was sent by Atlassian JIRA
(v6.2#6252)