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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2
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3
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4
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5
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Detailed explanation-1: -The main components of an encryption system are: (1) plaintext (not encrypted message), (2) encryption algorithm (works like a locking mechanism to a safe), (3) key (works like the safe’s combination), and (4) ciphertext (produced from plaintext message by encryption key).
Detailed explanation-2: -The encryption process step (step 4, above) is further broken down into five stages: Key transformation. Expansion permutation. S-Box permutation.
Detailed explanation-3: -The DES function has components-MCQSCENTER. Explanation : None.
Detailed explanation-4: -DES uses a 64-bit key 8 × 8 including 1 bit for parity, so the actual key is 56 bits. DES, in common with other block ciphers, is based around a structure called a Feistel Lattice so it is useful to describe how this works.