1. A server for use with a network to provide access to a computer configured for a different network without reconfiguring the computer through hardware or software comprising: 1) a registration module to register the computer to access the network; 2) a registration driver to assign IP addresses and maintain and access addressing information including IP addresses and MAC addresses; 3) an internal interface to connect the server to the computer; 4) an external interface to connect the server to the network; 5) a packet driver module to perform NAT at the internal interface 6) a packet filter that permits transmission of packets to and from the external interface based on registration status; 7) a DHCP module to service DHCP request based on assigned IP address; and 8) an ARP module that uses the registration driver to provide MAC address for an assigned IP address.