[asterisk-bugs] [Asterisk 0015784]: Simultaneous calls from same Call-ID silently ignored by asterisk

[Asterisk Bug Tracker]

A NOTE has been added to this issue. 
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https://issues.asterisk.org/view.php?id=15784 
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Reported By:                m0bius
Assigned To:                
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Project:                    Asterisk
Issue ID:                   15784
Category:                   Channels/chan_sip/General
Reproducibility:            always
Severity:                   minor
Priority:                   normal
Status:                     acknowledged
Asterisk Version:           SVN 
JIRA:                       SWP-221 
Regression:                 Yes 
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:             2009-08-27 05:40 CDT
Last Modified:              2009-10-23 12:45 CDT
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Summary:                    Simultaneous calls from same Call-ID silently
ignored by asterisk
Description: 
Hello everyone,

We have a follow-me system which terminates calls to an Asterisk server
which holds registrations for our VoIP users. In our follow-me system we
give the capability to the users to perform simultaneous follow-me to the
Asterisk Server (thus ringing two different voip accounts).

However I've noticed that on asterisk 1.6.1.1 and 1.6.1.4 when two calls
are sent simultaneously to different dialled numbers with the same Call-ID,
the second call does not enter the context. In a trace I did, I've seen
that asterisk responds to the SIP INVITE with Trying; however, that calls
stays there until it times out from the remote peer. 

The same thing has been tested on Asterisk 1.6.0.7 and 1.6.0.13 and it
works properly. I will attaching two traces (one from asterisk 1.6.0.7 and
one from asterisk 1.6.1.4)
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Relationships       ID      Summary
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related to          0016116 [patch] Fix/improve transaction/dialog-...
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 (0112673) davidw (reporter) - 2009-10-23 12:45
 https://issues.asterisk.org/view.php?id=15784#c112673 
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If two OKs get back to the caller, the RFC seems to require a valid
acceptance for both of them.  The caller is then allowed to send BYE,
immediately.

The very final part of section 16.7 says, effectively, that on forwarding
a 200 OK, the proxy MUST generate a Cancel for all the other forked calls. 
However, it also says that a race condition can result in more then one of
those calls having a 200 OK response.

Stateless proxies cannot fork. 

Issue History 
Date Modified    Username       Field                    Change               
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2009-10-23 12:45 davidw         Note Added: 0112673                          
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