ISC Exam Questions

Which of the following modes of DES is MOST likely used…

Which of the following modes of DES is MOST likely used for Database Encryption?

A.
Electronic Code Book (ECB)

B.
Cipher Block Chaining (CBC)

C.
Cipher Feedback (CFB)

D.
Output Feedback (OFB)

Explanation:
Electronic Code Book (ECB) works with blocks of data independently. As a result, data within a file does not
have to be encrypted in a specific order. This is extremely accommodating when making use of encryption in
databases.
Incorrect Answers:
B: Cipher Block Chaining (CBC) is mostly used for encrypting message data.
C: Cipher Feedback (CFB) is mostly used for encrypting message data.
D: Output Feedback (OFB) is used for encrypting digitized video or voice signals.

Harris, Shon, All In One CISSP Exam Guide, 6th Edition, McGraw-Hill, 2013, pp. 800-807