I just got hooked up last week. I'm using the modem Charter provided. It is a Motorola Surfboard. I had my second NIC in my PC (setup for DHCP) ready to go when the tech arrived. They will assign it (the modem) a gateway address (192.168.X.X). You can use that gateway address to hook up additional machines. So far I have had no problem with the service. The speed alone is worth it.
Tom Carey