Integrating VOIP with my existing phone system

Posted on 2006-06-08
Last Modified: 2010-04-12

I have a PABX phone system which has 3 Phones connected to our section of the office  i wish to add a VOIP box into the system so they can use the existing Phones and get the benefits of the cheaper VOIP rates.  I am unsure if i can do this, if anyone can tell me how to do this it would be great.

I would like all 3 phones to be able to pickup there existing phones and route through VOIP for outgoing calls and still receive incoming calls through the existing PABX system. how do I set this up, do i need 3 phone plugs at the router ????????


Question by:big_daddy_pimp
    1 Comment
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    Accepted Solution

    In order to do this you will need one or more spare FXO ports on your existing PBX (1 port will support 1 simultaneous call, 2 ports will support 2 calls etc...). You can then install something like Asterisk ( on a PC and fit a Digium TDM400 card ( with some FXS modules fitted.

    Configure your existing PBX to send all calls made with an 8 prefix out of the PXO interfaces. Asterisk will then handle the incoming calls and can be configured to automatically send the call onto a VoIP provider of your choice.

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