CompTIA Security Plus Mock Test Q874

Which of the following protocols uses TCP instead of UDP and is incompatible with all previous versions?

A. TACACS
B. XTACACS
C. RADIUS
D. TACACS+


Correct Answer: D
Section: Access Control and Identity Management

Explanation:
TACACS+ is not compatible with TACACS and XTACACS, and makes use of TCP.

Incorrect Answers:
A, B: TACACS and XTACACS make use of TCP and UDP.
C: RADIUS makes use of UDP.

References:
http://en.wikipedia.org/wiki/TACACS