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New Member

Answer Supervision

Hello all.The problem is with true answer.We have Cisco PRI connected to PBX(Tadiran Coral II) and PBX connected to telco with analog lines.So problem is when we call to city after first ring call already active and our billing

charging our clients without real answer.

Any help


New Member

Re: Answer Supervision

This might help:

1. Please explain what does it means “charging without real answer”? Do you get gap between real start time and CDR generated start time?

Also please describe from where your Call Accounting getting data feeds: PABX or from CISCO side?

2. Generally every PABX should support 2 types of answer supervision:

If you have CO Trunks with loop start signalling use specific Supervision on answer settings which will allow PABX to get true information about when call is answered using internal Tone/DTMF Cards (it is actually monitoring tones levels on the line and sence when the call is answered. I definitely know that ALCATEL and AVAYA support the above stated feature)

3. Get CO trunk card that supports reverse line answer or ground start signalling on analogue lines. Also make sure that this type of lines are provided and supported by your TELCO (usual analogue PSTN use local loop signalling). Using this type of signalling PABX will definitely sense when call starts.

I believe there is no problem on PRI side because there should nob be probleme with ISDN.