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Simulate PSTN for POTS modems

Hello all,


I need to be able to remote manage about 10 routers using dial-up modems. It's kind of an old school way of doing things I know, but unfortunately, the sites are in rural areas, most of which have only one ISP option and bad or no cell service. Also, some of the sites are not easily accessible and none have anyone who works there under normal circumstances. They all do have a POTS line.


I have a plan for implementing the modems, but what I really need is to set up a simulated PSTN so that I can test and preconfigure the modems and routers at my office instead of trying to do it remotely which would be a real pain.


I have been researching, but have been unable to come up with exactly what I will need to accomplish the goal. Most of the info I have found has to do with VOIP phones and the little that I have found that does deal with POTS starts way after the equipment is set up with not much info about what is required to get started in the first place.


So my question is, first, can I obtain some combination of routers and modules that will allow me to connect two modems and dial back and forth between them as if they were at remote locations and secondly, what will I need to accomplish this? It can be a simple setup. I do not need to worry about VOIP or connecting the test lab to the real PSTN. I have access to quite a few older routers and switches (2811s, 2620s, 1721s, 2960s, 3550s, 3750s) and I figure I will just need some modules and some knowhow, but  I cant find a direct answer to that question.


Thanks for the help.


Re: Simulate PSTN for POTS modems

You can use that 2811 or 2821 if you have one and put some T1 cards in there, then make T1 cables and connect the router and modems together. You'll have to do some configurations on the router.


Re: Simulate PSTN for POTS modems

I have 3 2811s and z as bunch of wic1t And cables so that’s not a problem, but what do I need to connect the modems and create dial tone for them?


i think I need A couple of  FXO modules to connect the modems, but I’m not sure if that’s all. 


Re: Simulate PSTN for POTS modems

You would use FXO for one router as your PSTN backbone and have FXS on the branch routers. What kind of modems are you using?


Re: Simulate PSTN for POTS modems

I have usr courier modems.

So it sounds like I would need two routers with FXOs for each of the two modems and another router with 2 FXS cards for the PSTN and wic1t cards for the connections between the routers?
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