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New Member

1751 connection to PBX for VoIP - just a simple HOWTO.


Does anyone have any pointers for configuring a 1751 BRI connected to a Siemens PBX?

I have a 2/FXS VIC and a VIC-2BRI in 2 x 1751 routers connected via a serial line.

Phones plugged into each router on the FXS port have no problem communicating, also over the serial connection, however I am at a slight loss as to how I should configure the VIC-BRI port to communicate with the PBX so that I may use the phones within the company (behind the PBX) to communicate via the pbx->router->serialline->router->pbx to the phones in the branch office.

The connection between the router and the PBX is fine, q921 and q931 signalling checks out.

Serial line is using "ip unnumbered loopback 0".

Is it possible to call "into" the office from the FXS port as well? And Vice versa?

Sorry, not much experience in VoIP setup - any help much appreciated.

I have searched, but have not found what I am looking for.

Also, the "isdn incoming-voice voice" command which is often refered to does not appear on my IOS {12.2(8)T1} (not even hidden)

Any additional info on the Siemens side I should know? PBX has been set up as Master.


  • Video Over IP
New Member

Re: 1751 connection to PBX for VoIP - just a simple HOWTO.

Please ignore message....

I've just realized this is posted in wrong forum - You may remove it as I have just put it in the correct forum.

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