[This is preliminary documentation and subject to change]
You can require users to provide a valid Microsoft Windows user-account name and password before they access any information on your server. This identification process is called authentication. Authentication, like many of the features in IIS, can be set at the FTP site, directory, or file level. IIS provides the following authentication methods to control access to the content on your FTP server:
| Method | Security Level | Sends Passwords How? | Usable Across Proxy Servers and Firewalls? | Client Requirements |
| Anonymous FTP | None | N/A | Yes | Any FTP client |
| Basic FTP | Low | Clear text | Yes | Any FTP client |