Virtual servers on the Internet are the same as virtual servers on an intranet. You must register your domain names in the worldwide Domain Name System through the InterNIC. The InterNIC is a cooperative activity between the National Science Foundation, Network Solutions, Inc., and AT&T to provide DNS registration services to the worldwide Internet community. You can reach the InterNIC at http://internic.net. Some Internet service providers register domain names with the InterNIC for you.
If your Internet clients use Internet Explorer version 2.0 or later, you can use Windows NT groups for secure authentication by using challenge/response authentication. Netscape Navigator and other browsers do not support secure authentication by using challenge/response. They use Basic authentication, which transmits user names and passwords by using base-64 encoding. Base-64 encoding can be decoded easily. Because anyone monitoring the network can decode these user names and passwords, using Basic authentication on public networks is not recommended.
Once authenticated, either by challenge/response or Basic authentication, all data is transmitted in clear text. You can use Secure Sockets Layer (SSL) to encrypt all data, but SSL uses a lot of processor time to encode and decode every shred of data passed through Internet Information Server. Therefore, SSL is usually reserved for small amounts of private information, such as credit card numbers or addresses.
For more information about SSL, see Chapter 3, "Server Security on the Internet."