[asterisk-bugs] [Asterisk 0015452]: Unable to make ISDN PRI calls after upgrade.

[Asterisk Bug Tracker]

A NOTE has been added to this issue. 
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https://issues.asterisk.org/view.php?id=15452 
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Reported By:                alecdavis
Assigned To:                
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Project:                    Asterisk
Issue ID:                   15452
Category:                   Channels/chan_dahdi
Reproducibility:            always
Severity:                   major
Priority:                   normal
Status:                     new
Asterisk Version:           SVN 
Regression:                 No 
SVN Branch (only for SVN checkouts, not tarball releases): N/A 
SVN Revision (number only!): 203077 
Request Review:              
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Date Submitted:             2009-07-05 21:50 CDT
Last Modified:              2009-07-08 05:42 CDT
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Summary:                    Unable to make ISDN PRI calls after upgrade.
Description: 
After upgrade to SVN-trunk-r204919M from SVN-branch-1.6.2-r203077M we are
unable to make ISDN PRI calls.

reverting back to 1.6.2-r203077M with exactly same configs, works again.

Console output as attached files.

The difference is the extra "Ext: 1  DS1 Identifier: 0" that's not present
using older code.

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---------------------------------------------------------------------- 
 (0107473) alecdavis (reporter) - 2009-07-08 05:42
 https://issues.asterisk.org/view.php?id=15452#c107473 
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excerpt from ITU Q.931 (05/98)

4.5.13 Channel identification
The purpose of the Channel identification information element is to
identify a channel within the
interface(s) controlled by these signalling procedures.
The Channel identification information element is coded as shown in
Figures 4-18 and 4-19 and
Table 4-13. The channel identification element may be repeated in a
message, e.g. to list several
acceptable channels during channel negotiation.
The default maximum length for this information element is network
dependent
<pre>    8       7       6       5       4       3       2       1     
Octet
o-------o-------o-------o-------o-------o-------o-------o-------o
|     Channel identification information element identifier     |
|   0   |   0   |   0   |   1   |   1   |   0   |   0   |   0   |  1
o-------o-------o-------o-------o-------o-------o-------o-------o
|         Length of channel identification contents             |  2
o-------o-------o-------o-------o-------o-------o---------------o
|  ext  |Int Id | Int   | Spare | Pref  |D-Chan | Info Channel  |  3
|   1   |Present| Type  |   0   | Excl  |  Ind  |  Selection    |
o-------o-------o-------o-------o-------o-------o-------o-------o
|  ext  |             Interface Identifier                      |  3.1
|  0/1  |                                                       | (Note
1)
o-------o-------o-------o-------o-------o-------o-------o-------o
|  ext  |   Coding      |Number |       Channel type            |  3.2
|   1   |   Standard    | /Map  |        / Map element Type     | (Note 2
& 5)
o-------o-------o-------o-------o-------o-------o-------o-------o
|                  Channel number/Slot map (Note 3)             |  3.3
|                                                               | (Note
2,4 & 5)
o-------o-------o-------o-------o-------o-------o-------o-------o</pre>

NOTE 1 – When the "interface identifier present" field in octet 3
indicates "interface implicitly identified" octet 3.1 is omitted. When
octet 3.1 is present, it may be extended by using the extension bit (bit
8).

NOTE 2 – When the "interface type" field in octet 3 indicates "basic
interface", octets 3.2 and 3.3 are functionally replaced by the
"information channel selection" field in octet 3,and thus omitted.

NOTE 3 – When channel number is used and a single channel is indicated,
bit 8 shall be set to "1". When channel number is used and multiple
channels are indicated, bit 8 shall be used as an extension bit to indicate
an extension to subsequent channels and coded according to the rules
specified in 4.5.1.

NOTE 4 – When channel number is used, this octet may be repeated to
indicate multiple channels.

NOTE 5 – These octets shall be omitted when the entire interface is to
be identified. 

Issue History 
Date Modified    Username       Field                    Change               
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2009-07-08 05:42 alecdavis      Note Added: 0107473                          
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