Without more detail on what cable company, what modem, what network interface you computer has, and anything special that you might have to do to connect, the basic answer is:
  • 1) Boot The Knoppix Live CD
    2) USe the browser to access the Internet.
Knoppix generally should take care of all DHCP setup for you and the net shoud be available when you boot.

I do suggest that anyone who has a high speed connection use one of the very inexpensive DSL/cable routers available. This will give you added utility and an extra level of hardware firewall protection, but this is more important with Windows than with a live CD. A router will also take care of any logging in that needs to be done (this is usually needed with DSL, but not typical with cable).

If you can't connect and there is no obvious reason (very new on-board IC and a very old copy of Knoppix, USB interface to connect, login required by the cable company), then you just might have a problem I have seen after installing a Windows "security update". See these threads for details, but I hope it is not that: http://www.knoppix.net/forum/viewtop...er=asc&start=0
and
http://www.knoppix.net/forum/viewtop...er=asc&start=0