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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16
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12
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11
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19
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Detailed explanation-1: -The Caesar cipher shifts all the letters in a piece of text by a certain number of places. The key for this cipher is a letter which represents the number of place for the shift. So, for example, a key D means “shift 3 places” and a key M means “shift 12 places”.
Detailed explanation-2: -The Caesar Cipher is a monoalphabetic rotation cipher used by Gaius Julius Caesar. Caesar rotated each letter of the plaintext forward three times to encrypt, so that A became D, B became E, etc., as shown in Table 4.6. Table 4.7 shows how “ATTACK AT DAWN” encrypts to “DWWDFN DW GDZQ” using the Caesar Cipher.
Detailed explanation-3: -Because there are only 25 possible keys, Caesar ciphers are very vulnerable to a “brute force” attack, where the decoder simply tries each possible combination of letters.
Detailed explanation-4: -In the generalized version of Caesar’s cipher each alphabet is replaced with another alphabet after shifting it x times to the right. The amount of the shift (x) is the encryption key. More items