Dial-Up Modem

[cbongard]

We are going to be installing a 3CX phone system soon and the office that will be receiving this phone system also requires the ability to use a dial-up modem for remote customer support. I was planning on using a SPA3102 ATA device, assigning an extension and connecting the PC 56k modem to this device. I know there has been a lot of discussion surrounding faxing and the ATA devices, but I couldn't find anything regarding 56k dial-up modems.

My questions are this:
1. Is this supported/will it work?
2. Are there any special considerations I will need?
3. Is there a different device better suited for this?

 

[leejor]

It might work, but at a reduced speed. VoIP is not the most ideal method to send analogue to digital to analogue data, as many people trying to use fax over VoIP have found. Fax has T.38 to help it cope in ideal situations, but regular data doesn't.
The problem is that you are taking digital information, converting it to tones, then sampling that at a given rate and converting it back to digital using a format that is able to drop or wait for some packets without much effect. With voice you might get a click/noise, or not even notice it, with data, it is unacceptable.

So, it might work running at 1200, 2400, or even faster. You definitely won't achieve anything close to 56K speeds.

 

[cbongard]

Thanks for this information. I will let you know how this works out for me...

 

[brianoakes]

How did this work out? I am having to do the same thing more or less.

 

[cbongard]

Unfortunately, it did not work out. I tried everything to make this work. We ended up brining in a POTS line for this modem (a critical device for support).

 

[leejor]

I have found that the newer built in laptop modems have a very difficult time establishing a connection with a 1200 or 2400 bps modem. You pretty much have to use an older modem at each location to go that slow.