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PREVENT VoIP and PBX outside-line incorrect use for hot-lines


we have a VoIP network connecting 3 branch offices each with a PBX.

We use FXS and FXO analog voice port in cisco 2600 routers connected to the PBXs.

Suppose one of the branch-office has telephone extensions numbering plan 5xx an 6xx (PBX extensions 501,502...,601,602...and so on).

In the cisco 2600 suppose I have 2 FXO voice ports connected to the PBX (extension 555 and 666 for example).

In router config I have theese dial-peers:

dial-peer voice 1 pots

description connected to PBX ext 555

destination-pattern 05..

forward-didits 3

port 1/0/0

dial-peer voice 2 pots

description connected to PBX ext 666

destination-pattern 06..

forward-digits 3

port 1/0/1

Suppose that from the outside (public PSTN) or from a telephone extension (es. 513) of the PBX one user sizes FXO port 1/0/0 and dials the digits 06089.

The dialed string matches the destination-pattern 06.. for FXO 1/0/1 .

What and how many digits the FXO 1/0/1 play-out to the PBX through FXO 1/0/1 ?

Is the "forward-digits" command enough ?

I don't want some users from the PBX or the outside can improperly use the PBX lines to call hot-lines sizeing one FXO router voice port and exiting from the other FXO port on the same router.

best regards


Re: PREVENT VoIP and PBX outside-line incorrect use for hot-line

Why don't you use 051 on voice port and 052 in anothe voice port , It can avoid confusion and use the system properly. To understand dial plans in detail refer this link :

New Member

Re: PREVENT VoIP and PBX outside-line incorrect use for hot-line

Hi,this is the situation

There are 30 outside PSTN lines connected to PABX.



From PSTN is possible to call directly each PBX extension, 555 and 666 too !

Each PBX extension (555 and 666 too) can seize PSTN lines.

I want to prevent anyone in PSTN from calling 555 and then throught router1 FXO1/0/1 and PBX redial and make international calls or calls to hotline.

I want outbound calls from FXO voice ports on router 1 can reach only PBX extensions 5xx or 6xx.

Is it possible configuring opportunely the router1 dial-peers ?


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