Which of the following is more suitable for a hardware implementation?

A.
Stream ciphers

B.
Block ciphers

C.
Cipher block chaining

D.
Electronic code book

Explanation:
Stream ciphers require a lot of randomness and encrypt individual bits at a time. This requires more processing
power than block ciphers require, which is why stream ciphers are better suited to be implemented at the
hardware level. Because block ciphers do not require as much processing power, they can be easilyimplemented at the software level.
Incorrect Answers:
B: Block ciphers can be easily implemented at the software level because they do not require as much
processing power as stream ciphers.
C: Cipher block chaining is a block encryption method where each block of text, the key, and the value based
on the previous block are processed in the algorithm and applied to the next block of text. Cipher block chaining
is not more suitable for a hardware implementation.
D: Electronic code book is a block encryption method. It is not more suitable for a hardware implementation.

Harris, Shon, All In One CISSP Exam Guide, 6th Edition, McGraw-Hill, 2013, p. 791