[seanmccann]

I called Comcast and had 2 options. Pay $50/month for unlimited or pay $25/mo for unlimited, but I would have to forgo using my own modem/router and use theirs. Decided to just pay the $50, but we'll see what happens. I could see them increasing the cap or forgiving overages for a few months.

[alerighi]

You must maybe use their modem (how they can check it I don't know, maybe they don't give you the configuration parameters for the network?) but you always have the possibility to add your own router after it and basically use their modem/router as a simple modem.

It's what I did in my country before they made illegal for ISPs to force you to use their modem/router, simply used the modem/router of the provider as a modem, forwarding all the ports to my own router that I used to do actual routing, WiFi access point and all other stuff that a router does.

[vict00ms]

They also charge you a monthly fee for using their modem.

[jaywalk]

The modem has to be authorized via MAC address on the network. They know the MACs of the modems they own, so it's very simple to know if a modem is theirs or not.

[eatbitseveryday]

I have Comcast and use my own modem and router. The requirement for the modem was simply one which supports at least DOCIS 3.0.