FXO card to replace T1

This may be a stupid question, but this is my first time dealing with FXO cards

I have a single T1 card that connects to the telco, with an internal modem bank, for our external branches to dial into.

Is it possible to replace the T1 card with a 4 port FXO card (and bring in 4 phone lines instead of 1), and achieve the same results? Or am I way off base? I am not looking to actually run any VoIP on this, it is purely for offices to dial-in through.

Thanks for any input.

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Comments

GT-Rob

I should mention its a MFT-T1, not a csu/dsu card

FattyAcid

GT-Rob wrote: »

I should mention its a MFT-T1, not a csu/dsu card

Technically, VWIC-MFT cards have CSU/DSU's in them too, but I understand what you're saying---and Cisco's way of wording things make this misleading.

So, you've got an ISDN T1 PRI coming into your router on the VWIC_MFT-T1 and you've got (I'm guessing) a NM-DM module in your router?

The FXO cards are VIC's--they can only do voice/fax.

Even if the FXO cards could be mapped to the internal digital modems (which they can't as far as I know) you wouldn't be able to do V.90/V.92 because the connection to the PSTN with the FXO ports is analog. Thus the fastest your external branch sites could connect at is 33.6 Kbps.

You could buy four external modems (quite cheap on the used market), an 4-port FXO module (for connecting to PSTN) and a 4-port FXS module (for connecting to the 4 external modems)--but again, you'd be limited to 33.6 Kbps.

Or you could buy a analog modem card for the router--WIC-1AM-V2, WIC-2AM-V2, NM-8AM-V2 and NM-16AM-V2, etc. Again, limited to 33.6 Kbps.

But in both cases, you're not using your internal digital modems at all.

GT-Rob

Awesome, thats about the track I was on. My biggest problem was mapping the FXO ports to the async lines (and could only see voice related commands).

I am just going to keep using the T1 card, with the single line in. It was just an upgrade thought.

kalebksp

GT-Rob wrote: »

Awesome, thats about the track I was on. My biggest problem was mapping the FXO ports to the async lines (and could only see voice related commands).

I am just going to keep using the T1 card, with the single line in. It was just an upgrade thought.

Perhaps I'm not understanding correctly, but a T1 can have 23-24 channels. How would four analog lines be an upgrade?