Which of the following is considered the weakest mode of DES

Which of the following is considered the weakest mode of DES?

A. Electronic Code Book

B. Cipher Block Chaining

C. Cipher Feedback

D. Output Feedback

Solution

A. Electronic Code Book (ECB) is fast and simple but is also the weakest mode of DES. Answer B is incorrect because Cipher Block Chaining (CBC) is not the weakest mode of DES. Answer C is incorrect because Cipher Feedback (CFB) is more secure than ECB and OFB. Answer D is incorrect because Output Feedback (OFB) is not the weakest, but it can’t detect integrity errors as well as CFB