[asterisk-bugs] [Asterisk 0012548]: SIP channel protocol illegally reverses direction when ringing channel AMI redirected (to parked channel)

[noreply at bugs.digium.com]

A NOTE has been added to this issue. 
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http://bugs.digium.com/view.php?id=12548 
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Reported By:                davidw
Assigned To:                oej
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Project:                    Asterisk
Issue ID:                   12548
Category:                   Channels/chan_sip/General
Reproducibility:            always
Severity:                   major
Priority:                   normal
Status:                     assigned
Asterisk Version:           SVN 
SVN Branch (only for SVN checkouts, not tarball releases):  1.4  
SVN Revision (number only!): 11463 
Disclaimer on File?:        N/A 
Request Review:              
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Date Submitted:             04-29-2008 09:47 CDT
Last Modified:              05-15-2008 13:08 CDT
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Summary:                    SIP channel protocol illegally reverses direction
when ringing channel AMI redirected (to parked channel)
Description: 
An outgoing call to a SIP channel was initiated using AMI Originate; the
first channel was a Local/ channel.  Whilst the call was still ringing, the
Local channel was AMI Redirected to a parked channel in the parking lot
(and drops out of the configuration).  A short time later, the call fails
within Asterisk, with the following diagnostics:

[Apr 27 11:09:03] WARNING[10117]: chan_sip.c:1948 retrans_pkt: Maximum
retries e
xceeded on transmission 4dd8e816320e6fac293336971fb18544 at 192.168.130.116
for seq
no 102 (Critical Response)
[Apr 27 11:09:03] WARNING[10117]: chan_sip.c:1972 retrans_pkt: Hanging up
call 4
dd8e816320e6fac293336971fb18544 at 192.168.130.116 - no reply to our critical
packe
t.

The destination phone continues to ring for some time after this.

If the call is answered before the Redirect, there is no problem.

Looking at the SIP traces indicates that Asterisk starts sending OK's (for
NOTIFY) in the same direction as it sent the NOTIFY's for the call setup. 
The called end ignores these.  If it answers after Asterisk has abandoned
it, it Asterisk ignores its OK's, in the correct direction, resulting in
the phone timing out before it considers the call dead.

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---------------------------------------------------------------------- 
 davidw - 05-15-08 13:08  
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Actually, it seems that the main masquerade logic doesn't deal with
bridging at all, at the moment.  One of the funnies in this case is that it
would normally be AppDial that dealt with Ring indications, and it would be
running on the previously bridged peer, whereas bridging is actually
running and it assumes that the both channels are already up, even though
it mostly works when one isn't.  Whilst UnPark could omit setting up the
bridge, without the bridge, there needs to be something else to supervise
the connection.

I have a feeling that acknowledging that bridging can run on channels
where one is not up, may be the better way forward. 

Issue History 
Date Modified   Username       Field                    Change               
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05-15-08 13:08  davidw         Note Added: 0086921                          
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