Crypto Ch 8

A major advance in symmetric cryptography occurred with the development of the rotor encryption/decryption machine.

True

A trap-door one-way function is easy to calculate in one direction and infeasible to calculate in the other direction unless certain additional information is known.

True

Asymmetric algorithms rely on one key for encryption and a different but related key for decryption.

True

Asymmetric encryption transforms plaintext into ciphertext.

True

Before the application of the public-key cryptosystem each participant must generate a pair of keys.

True

If the authenticator is encrypted with the sender's private key, it serves as a signature that verifies origin, content, and sequencing.

True

Much of the theory of public-key cryptosystems is based on number theory.

True

The defense against the brute-force approach for RSA is to use a large key space.

True

__________ are two related keys, a public key and a private key that are used to perform complementary operations, such as encryption and decryption or signature generation and signature verification. A)Asymmetric keys B)Key exchanges C)Symmetric keys D)Cipher keys

A)Asymmetric keys

A __________ is a cryptographic algorithm that uses two related keys, a public key and a private key. The two keys have the property that deriving the private key from the public key is computationally infeasible. A)Public Key (Asymmetric) Cryptographic Algorithm B)Private Key (Symmetric) Cryptographic Algorithm C)RSA Digital Cryptographic Algorithm D)Key Exchange Cryptographic Algorithm

A)Public Key (Asymmetric) Cryptographic Algorithm

The __________ indicates that the subscriber identified in the certificate has sole control and access to the private key. : A)Public Key Certificate B)Digital Signature C)PKI D)OAEP

A)Public Key Certificate

__________ depend on the running time of the decryption algorithm. A)Timing attacks B)Mathematical attacks C)Chosen ciphertext attacks D)Brute-force attacks

A)Timing attacks

The key used in symmetric encryption is referred to as a __________ key. A)secret B)private C)public D)decryption

A)secret

Asymmetric encryption can be used for __________ . A)neither confidentiality nor authentication B)both confidentiality and authentication C)authentication D)confidentiality

B) both confidentiality and authentication

The most widely used public-key cryptosystem is __________ . A)optimal asymmetric encryption B)RSA C)asymmetric encryption D)DES

B)RSA

Two issues to consider with the computation required to use RSA are encryption/decryption and __________ . A)asymmetric encryption padding B)key generation C)time complexity D)trap-door one-way functions

B)key generation

Public-key algorithms are based on __________ . A)substitution B)mathematical functions C)symmetry D)permutation

B)mathematical functions

A public-key encryption scheme has __________ ingredients. A)two B)six C)fourterm-23 D)eight

B)six

Public-key encryption is also known as ___________ . A)optimal-key encryption B)one way time exchange encryption C)asymmetric encryption D)digital-key encryption

C)asymmetric encryption

Plaintext is recovered from the ciphertext using the paired key and a _____________ . A)recovery encryption B)encryption algorithm C)decryption algorithm D)digital signature

C)decryption algorithm

The readable message or data that is fed into the algorithm as input is the ____________ . A)exchange B)ciphertext C)plaintext D)encryption

C)plaintext

Asymmetric encryption is also known as ___________ . A)digital-key encryption B)private-key encryption C)public-key encryption D)optimal encryption

C)public-key encryption

We define the ___________ of an algorithm to be f(n) if, for all n and all inputs of length n the execution of the algorithm takes at most f(n) steps. This is a common measure of the efficiency of an algorithm. A)one-way function B)OAEP C)timing attack D)time complexity

D)time complexity

A public-key encryption scheme is not vulnerable to a brute-force attack.

False

Asymmetric encryption can be used for confidentiality but not for authentication.

False

Asymmetric encryption utilizes only a public key for encryption and decryption.

False

Plaintext is transformed into ciphertext using two keys and a decryption algorithm.

False

Public-key encryption is more secure from cryptanalysis than symmetric encryption.

False

The encryption algorithm performs various transformation on the ciphertext.

False

Timing attacks are ciphertext attacks that are only applicable to RSA.

False