I have a few MikroTik routers that have USB ports which can be used for a USB 3g/4g modem.

I have no idea where to start with this. I'm in the southwestern US. The 4 major wireless service websites have no information that I can find. I went to a T-Mobile store and they couldn't understand why I can't "just use a mobile Wifi hotspot". I can't seem to find someone at a store who wants to talk about this.

My goal is to just have an additional way to connect to my router from the outside in case my ISP goes down (it does once in a while). At the very least it's just an out of band management connection. At best it would be an alternative internet connection when my cable ISP has problems. I don't care if it's IPv6 only.

Questions:

1. Is this possible in the SW United States?
2. What wireless company is easiest to deal with?
3. What USB modem do I buy? I bought an old one (formerly?) compatible with T-Mobile but I can't get it working anywhere other than Windows...

Once I actually get it working on the MikroTik I can move on to more advanced questions.

Was hoping someone could at least point me in a direction to start with a 3G/4G USB dongle.

Hi acruhl,

Have a look here for usb modems that works with Mikrotik. http://wiki.mikrotik.com/wiki/Supported_Hardware
The problem is that models change rather fast so the list above is never complete. It's not an official list but is user maintained. Older models are probably not available and newer Mikrotik compatible ones are not in the list. Also watch out for model revisions. Rev A1 might work with the Mikrotik but B1 does not. Then you gotta see whats available in your area and if it works with the local telco.