Which of the following cryptographic algorithms is MOST often used with IPSec?

Which of the following cryptographic algorithms is MOST often used with IPSec?

A.
Blowfish

B.
Twofish

C.
RC4

D.
HMAC

Explanation:
The HMAC-MD5-96 (also known as HMAC-MD5) encryption technique is used by IPSec to make sure that
a message has not been altered.
Incorrect Answers:
A: Blowfish can be used with IPSec but not as often as HMAC.
B: Twofish, a variant of Blowfish, can be used with IPSec but not as often as HMAC.
C: RC4 is popular with wireless and WEP/WPA encryption. IPSec can use HMAC-MD5 for data integrity.

Dulaney, Emmett and Chuck Eastton, CompTIA Security+ Study Guide, 6th Edition, Sybex, Indianapolis,
2014, pp. 139, 250, 251, 255-256, 260