Exam 1 MC pt.1

A __________ attack exploits the characteristics of the algorithm to attempt to deduce a specific plaintext or to deduce the key being used. A. ping-attack B. cryptanalytic C. malware D. brute-force

B

Combined one byte at a time with the plaintext stream using the XOR operation, a __________ is the output of the pseudorandom bit generator. A. digital signature B. keystream C. secure hash D. message authentication code

B

The most important symmetric algorithms, all of which are block ciphers, are the DES, triple DES, and the __________. A. SHA B. AES C. RSA D. DSS

B

The process of converting a ciphertext into plaintext. A. encryption B. decryption C. plaintext D. cryptography

B

The purpose of a __________ is to produce a "fingerprint" of a file, message, or other block of data. A. digital signature B. hash function C. secret key D. keystream

B

Which of the followings are drawbacks of OTP: A. Or modern high data-rate systems, a one-time pad cipher is totally impractical B. Pad must be securely transmitted to the recipient before the ciphertext can be decrypted. C. A pad (key) consisting of a randomly selected string of bits that is the same length as the message. D. The pad (key) is the same length as the message

B

__________ is a block cipher in which the plaintext and ciphertext are integers between 0 and n-1 for some n. A. SHA B. RSA C. AES D. DSS

B

__________ is the scrambled message produced as output. A. Secret key B. Ciphertext C. Plaintext D. Cryptanalysis

B

A _________ protects against an attack in which one party generates a message for another party to sign. A. data authenticator B. weak hash function C. strong hash function D. digital signature

C

Encrypt the word alphabet using a Caesar cipher with a shift of 3 A. DVSDULQV B. DOOFOHDU C. DOSKDEHW D. DORQHBHV

C

The key in one-time pad encryption _____ from session to session. A. remains constant B. is lengthened C. is replaced D. None of the answers are correct.

C

A __________ is to try every possible key on a piece of ciphertext until an intelligible translation into plaintext is obtained. A. hash function B. cryptanalysis C. mode of operation D. brute-force attack

D

Digital signatures and key management are the two most important applications of __________ encryption. A. preimage resistant B. advanced C. private-key D. public-key

D

If the only form of attack that could be made on an encryption algorithm is brute-force, then the way to counter such attacks would be to __________ . A. use shorter keys B. use more keys C. use less keys D. use longer keys

D

The original message or data that is fed into the algorithm is __________. A. encryption algorithm B. secret key C. decryption algorithm D. plaintext

D

__________ is a procedure that allows communicating parties to verify that received or stored messages are authentic. A. Cryptanalysis B. Decryption C. Collision resistance D. Message authentication

D

__________ is provided by means of a co-processor board embedded in the tape drive and tape library hardware. A. caesar cypher B. OTP C. vigenere cipher D. library-based tape encryption

D

There are two general approaches to attacking a symmetric encryption scheme cryptanalytic attacks and __________ attacks. answer was flubbed so short answer

brute force

A __________ is created by using a secure hash function to generate a hash value for a message and then encrypting the hash code with a private key. A. digital signature B. keystream C. secret key D. one way hash function

A

Also referred to as single-key encryption, the universal technique for providing confidentiality for transmitted or stored data is __________ . A. symmetric encryption B. Asymmetric encryption C. Public key encryption D. Message Digest

A

On average, __________ of all possible keys must be tried in order to achieve success with a brute-force attack. A. half B. one-fourth C. two-thirds D. three-fourths

A

The __________ is the encryption algorithm run in reverse. A. decryption algorithm B. plaintext C. ciphertext D. encryption algorithm

A

Transmitted data stored locally are referred to as __________ . A. data at rest B. ECC C. DES D. ciphertext

A