[asterisk-bugs] [LibPRI 0014507]: Regression in LibPRI regarding 64k data calls via ISDN

[Asterisk Bug Tracker]

A NOTE has been added to this issue. 
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http://bugs.digium.com/view.php?id=14507 
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Reported By:                jsmith
Assigned To:                mattf
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Project:                    LibPRI
Issue ID:                   14507
Category:                   General
Reproducibility:            always
Severity:                   minor
Priority:                   normal
Status:                     assigned
Asterisk Version:           1.4.23 
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:             2009-02-19 09:39 CST
Last Modified:              2009-02-25 16:43 CST
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Summary:                    Regression in LibPRI regarding 64k data calls via
ISDN
Description: 
There appears to be a regression in LibPRI between versions 1.2.3 and 1.2.4
regarding Asterisk's ability to pass through 64k data calls between ISDN
endpoints.
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Relationships       ID      Summary
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related to          0013118 Outgoing ISDN call blocked with cause (...
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 (0100760) jsmith (manager) - 2009-02-25 16:43
 http://bugs.digium.com/view.php?id=14507#c100760 
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After hurting my brain way too much trying to decipher the Q931 spec, I've
found that Asterisk is indeed sending an extra octet in the bearer
capabilities for unrestricted digital 64k data calls.  I'm posting the
patch here as opposed to bug 13118, as that one is very EuroISDN specific,
where this one is more generalized.

Matt, would you please take a look and make sure this makes sense? 
Essentially, my patch says "If you're doing a 64k unrestricted data call,
don't use user layer 3 and 3".  This seems to correspond with page 8-46 of
Telcordia SR-4994 (Issue 1, December 1999) which says:

64-kbps, unrestricted digital information, circuit-mode
 - Octets 4.1, 5, 5a, 6, and 7 not present

Before this patch, Asterisk was incorrectly sending octet 5 on 64k data
calls.  With this patch, it no longer does.  I've tested this patch against
a CO switch and a PRI test set (which was failing before the patch). 

Issue History 
Date Modified    Username       Field                    Change               
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2009-02-25 16:43 jsmith         Note Added: 0100760                          
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