CompTIA Security Plus Mock Test Q1035

Which of the following provides additional encryption strength by repeating the encryption process with additional keys?

A. AES
B. 3DES
C. TwoFish
D. Blowfish

Correct Answer: B
Section: Cryptography

Explanation:
Triple-DES (3DES) is a technological upgrade of DES. 3DES is still used, even though AES is the preferred choice for government applications. 3DES is considerably harder to break
than many other systems, and it’s more secure than DES. It increases the key length to 168 bits (using three 56-bit DES keys).

Incorrect Answers:
A: Advanced Encryption Standard (AES) has replaced DES as the current standard, and it uses the Rijndael algorithm. It was developed by Joan Daemen and Vincent Rijmen. AES is
the current product used by U.S. governmental agencies.
It supports key sizes of 128, 192, and 256 bits, with 128 bits being the default.
C: Twofish is quite similar to Blowfish and works on 128-bit blocks.
D: Blowfish is an encryption system invented by a team led by Bruce Schneier that performs a 64-bit block cipher at very fast speeds. It is a symmetric block cipher that can use
variable-length keys (from 32 bits to 448 bits).

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