[asterisk-bugs] [Asterisk 0012415]: chan_h323 doesn't respect rtp packetization settings

[noreply at bugs.digium.com]

A NOTE has been added to this issue. 
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http://bugs.digium.com/view.php?id=12415 
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Reported By:                pj
Assigned To:                
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Project:                    Asterisk
Issue ID:                   12415
Category:                   Channels/chan_h323
Reproducibility:            always
Severity:                   minor
Priority:                   normal
Status:                     new
Asterisk Version:           SVN 
SVN Branch (only for SVN checkouts, not tarball releases):  trunk 
SVN Revision (number only!): 113980 
Disclaimer on File?:        N/A 
Request Review:              
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Date Submitted:             04-10-2008 17:01 CDT
Last Modified:              04-11-2008 15:38 CDT
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Summary:                    chan_h323 doesn't respect rtp packetization settings
Description: 
chan_h323 ignores codecs payload settings eg. 'allow=g729:20'
h323 trace, when I call from h323 endpoint to asterisk:
Found peer capability G.729 <1>, Asterisk code is 256, frame size (in ms)
is 160

If I call from asterisk to another endpoing (eg. cisco gw), trace shows,
that is using 20ms g729 frame size, but still doesn't invoke p2p bridging
between sip and h323 channel

sip--->(g729/chan_sip)-asterisk-(chan_h323/g729)--->callmanager/(cisco gw
or cisco phone)
only g729 is allowed in h323 and sip config

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---------------------------------------------------------------------- 
 DEA - 04-11-08 15:38  
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I am not sure how to generate it with chan_h323, but we need
the ASN.1 call setup trace.

During the H.323 call setup, the endpoint first exchange their
maximum packetization capabilities, then they attempt to exchange
the desired packetization.

It appears, and I have not dug through the OpenH323 code to confirm this,
that the framing is being detected and based on the maximum capability
for a given codec and not the preferred framing.

If you have access to the CCM, can you check to see what the preferred
G729 framing is set to under 'Service Parameters'/'Call Manager Service'?

What happens if you replace the line :
ms = remoteCapabilities[i].GetTxFramesInPacket() * format.inc_ms;

with

ms = format.cur_ms; 

Issue History 
Date Modified   Username       Field                    Change               
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04-11-08 15:38  DEA            Note Added: 0085372                          
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