CAMA Trunks-reversal of tip and ring wire connections...

Unanswered Question
Sep 27th, 2011
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When I was going through Cisco Voice GWs and GKs book, I have read through the following.

When CAMA trunks configured with reversal of TIP and RIGN wiring connections to the PSTN, the voice call will go through but it will get disconnected after 15-30 secs with an error of "Timeout to receive signal from PSTN to send ANI (calling number).

Here is my query. When loopstart trunks have TIP and RING wire connections reversed, then will the voice call succeed first of all as it is a signalling mismatch with PSTN?



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acampbell Thu, 09/29/2011 - 07:10
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I think is to do with the CAMA trunk needing to observe the correct tip & ring (+ve & -ve) polarity as it depends on receiving the "line reversal signal" on called number answer to ensure that the ANI (CLI) is passed to the service.




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