[asterisk-dev] [Code Review] ETSI Call Waiting (Asterisk component)

[rmudgett at digium.com]

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This is an automatically generated e-mail. To reply, visit:
https://reviewboard.asterisk.org/r/568/
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Review request for Asterisk Developers.


Summary
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Add the ability to announce a call to an endpoint when there are no B channels available.
A call waiting call is a SETUP message with no B channel selected.

Relevant specification: EN 300 056, EN 300 057, EN 300 058

This is based off of the team/group/CCSS branch to get some architectural improvements.

For DAHDI/ISDN channels, the CHANNEL() dialplan function now supports the "no_media_path" option.
Returns "0" if there is a B channel associated with the call.
Returns "1" if no B channel is associated with the call.  The call is either on hold or is a call waiting call.

If you are going to allow incoming call waiting calls then you need to use CHANNEL(no_media_path) do determine if you must drop a call to accept the new call.

The libpri portion of this review is located in review:
https://reviewboard.asterisk.org/r/569/


Diffs
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  /team/group/CCSS/CHANGES 253243 
  /team/group/CCSS/channels/chan_dahdi.c 253243 
  /team/group/CCSS/channels/sig_pri.h 253243 
  /team/group/CCSS/channels/sig_pri.c 253243 
  /team/group/CCSS/configs/chan_dahdi.conf.sample 253243 
  /team/group/CCSS/configure.ac 253243 

Diff: https://reviewboard.asterisk.org/r/568/diff


Testing
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Party A ---> * ---> * ---> Party B

The link under test is between the two asterisk boxes.

1) Normal calls still work.
A calls B (Link under test is not congested.)
B answers
Call connects

2) Link congested and no B channel is released to take the call.
A calls B (Link under test is congested.  SETUP indicates no B channel.)
B answers
Call is immediately disconnected when B answers because there are no B channels.

3) Link congested and a B channel is released to take the call.
A calls B (Link under test is congested.  SETUP indicates no B channel.)
B channel is released on the link under test.
B answers
Call connects


Thanks,

rmudgett