You can require users to provide a valid Microsoft® Windows® user account name and password before they access any information about your server. This identification process is called authentication. Authentication can be set at the Web or FTP site, directory, or file level. IIS provides authentication methods to control access to your Web sites and FTP sites.

This section includes the following information:

• Anonymous Authentication in IIS 6.0: Describes how to configure anonymous authentication for IIS 6.0 and explains how to use the default anonymous user account, IUSR_ComputerName.
  
• Basic Authentication in IIS 6.0: Describes how to configure Basic authentication for IIS 6.0 and explains security considerations for the token cache.
  
• Digest Authentication in IIS 6.0: Describes how to configure both Digest authentication and sub-authentication in IIS 6.0.
  
• Advanced Digest Authentication in IIS 6.0: Describes how to configure Advanced Digest authentication in IIS 6.0.
  
• Integrated Windows Authentication in IIS 6.0: Describes how to configure Integrated Windows authentication in IIS 6.0. Integrated Windows authentication is the default authentication method for Windows Server™ 2003 operating systems.
  
• UNC Authentication in IIS 6.0: Describes how to configure UNC, or passthrough, authentication in IIS 6.0.
  
• .NET Passport Authentication in IIS 6.0: Describes how to configure .NET Passport authentication to work with IIS 6.0.
  
• FTP Site Authentication in IIS 6.0: Describes how to configure both anonymous and basic FTP site authentication in IIS 6.0.