Choose Single Computer and provide the Internet Protocol (IP) address to exclude a single computer. Choose Group of Computers and provide an IP address and subnet mask to exclude a group of computers. Press the button next to the IP address to use a domain name system (DNS) name instead of IP address. Your server must have a DNS server specified in its Transmission Control Protocol (TCP/IP) settings.
You are specifying, by IP address or domain name, which computer or group of computers will be granted or denied access. If you choose to, by default, grant access to all users, you will specify the computers to be denied access. If you choose to, by default, deny access to all users, you will then specify the specific computers to be allowed access. You should fully understand TCP/IP networking, IP addressing, and the use of subnet masks to use this option.
See also: The Internet Information Server Installation and Administration Guide. Choose Help Topics from Internet Service Manager, or click the Product Documentation icon in the Microsoft Internet Server program group.