212-81 practice question 19 of 30
Which of the following is a type of encryption that has two different keys. One key can encrypt the message and the other key can only decrypt it?
Full set: 206 questionsAsymmetric Public-key cryptography, or asymmetric cryptography, is a cryptographic system that uses pairs of keys: public keys, which may be disseminated widely, and private keys, which are known only to the owner. The generation of such keys depends on cryptographic algorithms based on mathematical problems to produce one-way functions. Effective security only requires keeping the private key private; the public key can be openly distributed without compromising security. Incorrect answers: Symmetric - Symmetric-key algorithms are algorithms for cryptography that use the same cryptographic keys for both encryption of plaintext and decryption of ciphertext. Block cipher - A block cipher is a deterministic algorithm operating on fixed-length groups of bits, called blocks. It uses an unvarying transformation, that is, it uses a symmetric key. Stream cipher - A stream cipher is a symmetric key cipher where plaintext digits are combined with a pseudorandom cipher digit stream (keystream). In a stream cipher, each plaintext digit is encrypted one at a time with the corresponding digit of the keystream, to give a digit of the ciphertext stream.
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- Question 1Which one of the following are characteristics of a hash function? (Choose two)
- Question 2Denis is looking at an older system that uses DES encryption. A colleague has told him th…
- Question 3When learning algorithms, such as RSA, it is important to understand the mathematics bein…
- Question 4Which of the following is a cryptographic protocol that allows two parties to establish a…
- Question 5What is the largest key size that AES can use?
- Question 6Which of the following would be the weakest encryption algorithm?
