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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48, 32
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64, 32
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56, 24
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32, 32
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Detailed explanation-1: -5. In the DES algorithm the round key is bit and the Round Input is bits. Explanation: The round key is 48 bits. The input is 32 bits.
Detailed explanation-2: -The DES (Data Encryption Standard) algorithm is a symmetric-key block cipher created in the early 1970s by an IBM team and adopted by the National Institute of Standards and Technology (NIST). The algorithm takes the plain text in 64-bit blocks and converts them into ciphertext using 48-bit keys.
Detailed explanation-3: -Data encryption standard (DES) is a block cipher that encrypts data in blocks of size 64 bits each. That is 64 bits of plain text goes input to the DES which produces 64 bit of cipher text. Key length is 56 bits.
Detailed explanation-4: -The DES keys are 64-bit, 128-bit, and 192-bit keys that use the DES algorithm to perform the cryptographic function. A 64-bit key is referred to as a single-length key. A 128-bit key is referred to as a double-length key.
Detailed explanation-5: -So the effective key length is 56 bits. DES consists of 16 “rounds”. Each round uses a roundkey, also called a subkey, derived from the main key.