easy
Single Answer
Which one of the following protocols is commonly used to provide back-end authentication services for a VPN?
Answer Options
A
HTTPS
B
RADIUS
C
ESP
D
AH
Correct Answer: B
Explanation
The Remote Authentication Dial-In User Service (RADIUS) protocol was originally designed to support dial-up modem connections but is still commonly used for VPN-based authentication. HTTPS is not an authentication protocol. ESP and AH are IPsec protocols but do not provide general authentication services for other systems.