COMPUTER ETHICS AND SECURITY
CRYPTOGRAPHY AND ENCRYPTION
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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32-bit
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48-bit
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54-bit
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42-bit
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Detailed explanation-1: -The DES algorithm uses a key of 56-bit size. Using this key, the DES takes a block of 64-bit plain text as input and generates a block of 64-bit cipher text.
Detailed explanation-2: -1) The correct answer is the first option: 48-bit.
Detailed explanation-3: -Triple DES provides a relatively simple method of increasing the key size of DES to protect against such attacks, without the need to design a completely new block cipher algorithm.
Detailed explanation-4: -Key size: larger key size means greater security (larger key space). Number of rounds: multiple rounds offer increasing security. Encryption modes: define how messages larger than the block size are encrypted, very important for the security of the encrypted message. Used in DES, IDEA, RC5 (Rivest’s Cipher n.