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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symmetric-key
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asymmetric-key
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Nither symmetric-key nor asymmetric-key
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Both symmetric-key and asymmetric-key
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Detailed explanation-1: -Data Encryption Standard (DES) is an outdated symmetric key method of data encryption. It was adopted in 1977 for government agencies to protect sensitive data and was officially retired in 2005.
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: -DES takes a 64-bit plaintext and produce a 64-bit ciphertext; at the decryption site, DES takes a 64-bit ciphertext and produce a 64-bit block of plaintext. The same 56-bit cipher key can be used for both encryption and decryption. The key nature of DES is that the algorithms is fixed and is public data.
Detailed explanation-4: -The use of the DES algorithm was made mandatory for all financial transactions of the U.S. government involving electronic fund transfer, including those conducted by member banks of the Federal Reserve System.