What is the correct port for PBX and Gateway

Hi, just want a quick answer, what will I use if I connect a PBX system and a Cisco Gateway.
My answer is E&M for trunking but is it possbile to use FXO from Gateway and FXS from PBX.

as FXO provide tones to FXS ?
Am I right?
thanks

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Comments

nice343

you can use a

fxo, e&m and T1 with cas signaling

MACattack

Okay, from cisco gateway I can use FXO or Eand M or as you SAID CAS or Rob Bits Signaling.

But is there any article that FXS can be used just to make safe.

nice343

MACattack wrote:

Okay, from cisco gateway I can use FXO or Eand M or as you SAID CAS or Rob Bits Signaling.

But is there any article that FXS can be used just to make safe.

I cannot speak for articles and books but I can definetly speak from my experience and from what I know you cannot connect an fxs port on a cisco router or gateway to PBX.

FXS stands for foreign exchange station, it connects to anolgue phones, faxes and modems not PBX

mikej412

If you're going to use analog ports, then E&M would be preferred.

If you used an FXO port, you'd connect it to an FSX port. But if the FXO port was the PBX, then you'd have to use an FXS port on the Cisco side.

Are you sure you wouldn't prefer a nice digital connection instead?

MACattack

Thanks for all replies, well mike I will use digital interface like T1/PRI CAS.