
to Cable Forum
Any device plugged into a cable modem will work with DHCP - no need to register (make sure you power off and power on the modem again after any change of connection).
STBs require registration of the device, by mac addy. after changing over the connected device, and rebooting the modem, you should be taken automatically to ntl's registration page. You'll need the customer account PID and password.
As this relates to connection of a router, thread moved to Computers & IT