Cable modem replaced

On Monday night, the network in our house failed. The network inside worked, but we had lost connectivity. I hoped for a while it would just start working again -- and they don't exactly advertise how to get in touch with them. Today, we got through and they sent someone out who replaced our cable modem. The network in the house still wasn't working, however, so I came home a bit early to work on it. It took me a few tries to get it work properly -- at first, it would assign 192.168.100.x addresses to the router, as if the modem was trying to NAT for us. But after a few powerycles and resets, I got it to assign us a real address and now everything appears to be working fine. I don't know what will happen if it loses power, though. I was pleased with the previous modem because it seemed extremely stable.