[asterisk-bugs] [Asterisk 0014385]: Unhold fails if first SDP on OK, particularly Cisco CCM 6

[Asterisk Bug Tracker]

A NOTE has been added to this issue. 
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http://bugs.digium.com/view.php?id=14385 
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Reported By:                davidw
Assigned To:                
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Project:                    Asterisk
Issue ID:                   14385
Category:                   Channels/chan_sip/Interoperability
Reproducibility:            always
Severity:                   major
Priority:                   normal
Status:                     new
Asterisk Version:           1.6.0.1 
Regression:                 No 
SVN Branch (only for SVN checkouts, not tarball releases): N/A 
SVN Revision (number only!):  
Request Review:              
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Date Submitted:             2009-02-02 06:39 CST
Last Modified:              2009-05-07 10:30 CDT
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Summary:                    Unhold fails if first SDP on OK, particularly Cisco
CCM 6
Description: 
Cisco CCM 6 appears never to send SDP on the INVITE, so Asterisk
effectively makes the offer, even when the Cisco is re-inviting because a
CCM hosted phone has gone on hold.  Asterisk sets up its SDP from flags[1]
in the channel private data structure, which means that, if the channel was
on hold, it will offer a=inactive (observed, although a=recvonly also seems
possible).  Even if the CCM intended to unhold, the only possible response
to an a=inactive offer, is a=inactive.  Asterisk should only actually use
saved state if it is making the response.  For an offer, as it looks like
it can never locally hold, it should offer a=sendrecv.
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Relationships       ID      Summary
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related to          0014448 [patch] chan_sip fails to remove hold w...
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 (0104361) davidw (reporter) - 2009-05-07 10:30
 http://bugs.digium.com/view.php?id=14385#c104361 
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I've been trying to port these patches to 1.6.1.0.  Although, unfortunately
I don't have permission to post resulting patches, it seems to me that, to
avoid noise, revision 65401 really ought to qualify the reporting (event,
history and notifyhold) by whether one is trying to go from held to held. 
unheld to unheld seems OK, as the calling code does the check, but, if I
understand things correctly, held to held cannot be filtered at that stage
because there may be a change between different types of held.  Maybe it is
worth doing belt and braces and testing for no change, rather than held to
held. 

Issue History 
Date Modified    Username       Field                    Change               
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2009-05-07 10:30 davidw         Note Added: 0104361                          
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