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7750 Analog PBX Integration

What would the configuration look like if I needed to do the following.

ICS7750 Analog Bundle Machine (Does not support voice calls over WIC-T1).

Remote Site:

7750 FXS connected FXO in 2600. 2600 has serial connection to the core site.

Core Site:

2600 FXO connected to PBX

First of all, will this work? Second of all here is my theory. CallManager Route Pattern of 1XX (extensions are 1XX at the core site) send to MRP300 with FXO card. At the MRP300 a dial-peer pots of 1XX send out FXO port. On the remote 2600 a dial-peer voip of 1XX with a session target to the IP of serial interface on the Core router. On the core router a dial-peer pots with a destination pattern of 1XX out FXO port connecting to PBX (15 year old Merlin). I tried this configuration and every call I made would get sent to the PBX extension of the phone administrator who has his PBX set up to send any calls to non-existent station ids sent to his extension. So I think this is working but for some reason the digits the PBX is getting is wrong, or could the PBX be doing something weird with the digits it gets?

Then would I just reverse engineer it to get the call back to CallManager? I would really love to get some closure on this issue. Thanks in advance.

Community Member

Re: 7750 Analog PBX Integration

Not sure how much this is going to help you but thought you might want to take a look at it.....

Cisco IP Telephony Network Design Guide


Re: 7750 Analog PBX Integration

Don't forget that by default, POTS dial peers will strip off any explicitly matched digits that are configured on the destination pattern. For example, if you have a destination pattern of '1...', the 1 will be assumed to be a access code and only the '...' digits will be sent out the port. To get around this behaviour, use the prefix command to prepend any stripped digits again, or add 'forward-digits all' on the POTS dial peer to send all digits out the voice port.


Re: 7750 Analog PBX Integration

Excellent information. I will be able to test this in a few days. Just for curiosity sake, is the no digit strip command the same as the above commands?


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