I need to find a way to prevent certain computers or users on a office network from having Internet access. The client machines are Windows XP and 2000 Pro computers that obtain their private IP address from the DHCP service on a Win2K Server. There's a Netgear FVS318 ProSafe VPN Firewall router that gives all computers DSL Internet access through NAT. The Win2K Server forwards Internet DNS requests to the Netgear router. As far as I can tell by the manual, the Netgear router doesn't have a built-in way to block specific computers. Any ideas how to block Internet access? The block can be at the client machines, Win2K, or the router.