[asterisk-bugs] [Asterisk 0013034]: 183 response although progressinband=never

[Asterisk Bug Tracker]

A NOTE has been added to this issue. 
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http://bugs.digium.com/view.php?id=13034 
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Reported By:                klaus3000
Assigned To:                
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Project:                    Asterisk
Issue ID:                   13034
Category:                   Channels/chan_sip/Interoperability
Reproducibility:            always
Severity:                   minor
Priority:                   normal
Status:                     new
Asterisk Version:           1.4.21 
SVN Branch (only for SVN checkouts, not tarball releases): N/A 
SVN Revision (number only!):  
Disclaimer on File?:        N/A 
Request Review:              
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Date Submitted:             2008-07-09 07:03 CDT
Last Modified:              2008-10-30 11:38 CDT
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Summary:                    183 response although progressinband=never
Description: 
Hi!

Scenario with Asterisk 1.4.21.1:

SIP Client ----> chan_sip:Dial(zap):chan_zap ---> ISDN

very simple dialplan:
[fromklaus]
exten => _1X.,1,NoOp(1... SIP: Outgoing Call: Asterisk->HiCom)
exten => _1X.,n,Dial(Zap/g1/${EXTEN:1})

Immediately after sending the SETUP message, Asterisk responds with 183
Session Progress. Thus, the SIP client is waiting for inband audio, but
there is no inband audio available. progressinband=never

sip.conf:

[klaus]
type=peer
username=klaus
host=dynamic
context=fromklaus
canreinvite=no
progressinband=never


actually I tried all progressinband settings without any difference
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 (0094419) klaus3000 (reporter) - 2008-10-30 11:38
 http://bugs.digium.com/view.php?id=13034#c94419 
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> However, I think the bigger question is, why is no media actually getting
to the endpoint? 

I think this one is easy - there is no media. As you see in the Q.931
response messages there is no indication that there will be inband audio -
which means: there is no inband audio.

Thus, why is 183 sent? MAybe because core receive a frame from chan_zap.
Thus, why does chan_zap send a frame to core when there is no inband audio? 

Issue History 
Date Modified    Username       Field                    Change               
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2008-10-30 11:38 klaus3000      Note Added: 0094419                          
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