The FortiGate unit can be configured to allow authentication to a RADIUS server. The RADIUS server can use several different authentication protocols during the authentication process. Which of the…

MS-CHAP-V2 is a widely supported and more secure version of the Challenge-Handshake Authentication Protocol commonly used with RADIUS for authentication, providing mutual authentication and stronger encryption.

PAP (Password Authentication Protocol) is a basic authentication protocol supported by RADIUS, though it transmits credentials in clear text and is less secure.

CHAP (Challenge-Handshake Authentication Protocol) is a challenge-response authentication protocol supported by RADIUS, offering more security than PAP by not sending the password in clear text.

MS-CHAP (Microsoft Challenge-Handshake Authentication Protocol v1) is a Microsoft-specific challenge-response protocol used with RADIUS, providing a more secure alternative to PAP for Windows clients.

FAP (FortiGate Authentication Protocol) is not a recognized or standard authentication protocol used by RADIUS servers.