Keep up to date on the latest patches and configuration issues. Sec uring the machine and its operating system is the first step. Now, you need to get a handle on who can browse your server. Information on your company's Web servers probably will vary in content sensitivity. You may need to keep track of who accesses which servers and from where.
Firewalls can help restrict traffic to the server.
Once users have reached the server, access controls restrict them to certain content. You may want to restrict access to a page or set of pages by user names and passwords, by IP address or by groups. If you've got a company firewall, you'll have to decide where to put your Web server. You may want an internal Web server for your intranet applications and another Web server outside of your firewall for outside users. This setup could be a problem if you want remote users to have access to internal databases through a Web interface.