[asterisk-bugs] [Asterisk 0017012]: [patch] endless wait for RTP when both legs have a=direction:passive in SDP

[Asterisk Bug Tracker]

A NOTE has been added to this issue. 
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https://issues.asterisk.org/view.php?id=17012 
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Reported By:                wdoekes
Assigned To:                
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Project:                    Asterisk
Issue ID:                   17012
Category:                   Channels/chan_sip/General
Reproducibility:            always
Severity:                   feature
Priority:                   normal
Status:                     confirmed
Asterisk Version:           1.4.30-rc3 
JIRA:                       SWP-1086 
Regression:                 No 
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:             2010-03-12 02:34 CST
Last Modified:              2010-04-27 08:10 CDT
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Summary:                    [patch] endless wait for RTP when both legs have
a=direction:passive in SDP
Description: 
A Dialogic machine that I'm peering with has the ability to go into passive
mode for RTP traffic (adding a=direction:passive to the SDP body). I
haven't figured out why/when it does so, but when it does -- and it always
does in my current setup -- everyone ends up waiting for data and no RTP
stream gets set up.
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 (0120961) frawd (reporter) - 2010-04-27 08:10
 https://issues.asterisk.org/view.php?id=17012#c120961 
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A few questions/comments:
- Could the 'prod' be done only if nothing is received in a certain amount
of time after answer (see __ast_answer in channel.c, "Didn't receive a
media frame")?
- Does this only apply to SIP/RTP or can it be safely done in the global
ast_answer in channel.c?
- In that case, should this only be done in case of audio streams, or does
this apply to to any RTP stream (video/image/..)?
- Maybe a configuration parameter (global and/or per-line) could activate
the RTP 'prodding'.

I also saw a way to generate a silent audio frame instead of putting
garbage in, maybe it could help:
http://lists.digium.com/pipermail/asterisk-dev/2009-May/038416.html 

Issue History 
Date Modified    Username       Field                    Change               
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2010-04-27 08:10 frawd          Note Added: 0120961                          
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