Chapter 3 Authentication for FortiOS 5.0 : Configuring authenticated access : Authentication in security policies : Enabling authentication protocols
  
Enabling authentication protocols
Users can authenticate using FTP, HTTP, HTTPS, and Telnet. However, these protocols must be enabled first.
Another authentication option is to redirect any attempts to authenticate using HTTP to a more secure channel that uses HTTPS. This forces users to a more secure connection before entering their user credentials.
To enable support for authentication protocols - web-based manager
1. Go to User & Device > Authentication > Settings.
2. Select one or more of HTTP, HTTPS, FTP, Telnet, or Redirect HTTP Challenge to a Secure Channel (HTTPS). Only selected protocols will be available for use in authentication.
3. Select the Certificate to use, for example Fortinet_Factory.
4. Select Apply.
To enable support for authentication protocols - CLI
config user setting
set auth-type ftp http https telnet
set auth-cert Fortinet_Factory
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