Which of the following authentication protocols uses a 3-way authentication handshake?

A.
CHAP

B.
EAP

C.
Kerberos

D.
PAP

Explanation:
Answer A is correct; CHAP (Challenge Handshake Authentication Protocol) uses a 3-way authentication handshake.

Incorrect Answers and Explanations: B, C, and D: Answers B, C, and D are incorrect. EAP is the Extensible Authentication Protocol, an authentication framework describing multiple authentication methods. Kerberos is a Single Sign On system which using tickets. PAP is the Password Authentication Protocol, which is simpler (and has less steps) than CHAP.