[asterisk-bugs] [Asterisk 0016625]: RFC2833 DTMF is not passed correctly when going SIP->IAX2->SIP

[Asterisk Bug Tracker]

A NOTE has been added to this issue. 
====================================================================== 
https://issues.asterisk.org/view.php?id=16625 
====================================================================== 
Reported By:                sharvanek
Assigned To:                
====================================================================== 
Project:                    Asterisk
Issue ID:                   16625
Category:                   Channels/chan_iax2
Reproducibility:            always
Severity:                   major
Priority:                   normal
Status:                     needs license
Asterisk Version:           1.4.28 
JIRA:                        
Regression:                 No 
Reviewboard Link:            
SVN Branch (only for SVN checkouts, not tarball releases): N/A 
SVN Revision (number only!):  
Request Review:              
====================================================================== 
Date Submitted:             2010-01-17 12:02 CST
Last Modified:              2010-01-18 00:47 CST
====================================================================== 
Summary:                    RFC2833 DTMF is not passed correctly when going
SIP->IAX2->SIP
Description: 
We were the victims of the Sonus bug, we've patched appropriately however
we're still having an interesting issue.

SIP->Asterisk->SIP->Sonus works fine now for DTMF via RFC2833 using the
attached patch.

However if you toss IAX2 in the middle (even with both asterisk boxes
patched) DTMF is unreliable, (jitterbuffer is off).

SIP Phone->Asterisk->IAX2->Asterisk->SIP->Sonus

Attached are packet captures from the last asterisk box in the path to
Sonus for both SIP (working) and IAX2 (not working).

If we substitute the IAX2 trunk for SIP (still using the two asterisk
boxes) DTMF works flawlessly, something is getting lost when going over
IAX2 and we'd like to figure out what that is and get it corrected.

Thanks

====================================================================== 

---------------------------------------------------------------------- 
 (0116799) sharvanek (reporter) - 2010-01-18 00:47
 https://issues.asterisk.org/view.php?id=16625#c116799 
---------------------------------------------------------------------- 
Roger that, yea this 100% fixes the DTMF issue with Sonus switches (Level3,
GBLX etc.).

We're just trying to figure out why if IAX2 gets in the middle it breaks,
I suspect something is missing in my patch that IAX2 doesn't like in the
RTP stream (odd) or something else needs to be patched as well.

I look forward to seeing what we can figure out. :)

-SH 

Issue History 
Date Modified    Username       Field                    Change               
====================================================================== 
2010-01-18 00:47 sharvanek      Note Added: 0116799                          
======================================================================