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Connecting Cisco 3825 - FXO with PBX FXS

I need to integrate Cisco 3825 with PBX (Iwatsu). PBX vendor advise me to provide 1x 4 Port FXO card to connect to PBX 4 Port FXS card.. another 1x 4 Port FXS card to connect to PBX 4 Port FXO card. We have about 30 analog phones at the PBX system. I need both way communication between the cisco IP phone and 30 analog phones. Any idea do this work?

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Re: Connecting Cisco 3825 - FXO with PBX FXS


Your vendor is correct, you need both FXS and FXO cards so you can directly dial extensions in both directions. Basically the router will dial on FXO ports, and receive calls on FXS. There are also two-ports cards that you can use. Remember in the router you will also need a minimum of PVDM2-8 for DSP resources.

The alternative is to use ISDN BRI if available on the PBX, that would give you a much simple configuration, and more features.

Hope this helps, please rate post if it does!

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