Network Security Topic 8

What is the primary goal of cryptography?

• To keep secrets secret

• To prevent data modification

• To authenticate users

• To ensure data availability

What type of attack involves trying all possible keys to decrypt a message?

• Man-in-the-middle attack

• Replay attack

• Brute-force attack

• Ciphertext attack

Which cryptographic primitive uses a single key for both encryption and decryption?

• Asymmetric encryption

• Hash function

• Digital signature

• Symmetric encryption

What is the term for the unreadable form of data after encryption?

• Plaintext

• Ciphertext

• Key

• Hash

Which of the following describes a hash function?

• It requires a secret key for decryption.

• It generates a fixed-size output from variable-size input.

• It is a type of symmetric encryption.

• It encrypts data using a public key.

Which cipher is an example of a monoalphabetic substitution cipher?

• AES encryption

• RSA algorithm

• Caesar cipher

• Vigenere cipher

What is the main purpose of digital signatures?

• To encrypt data

• To provide non-repudiation

• To ensure data availability

• To generate random keys

Which of the following is a characteristic of asymmetric encryption?

• Uses a single key for encryption and decryption

• Does not require a key

• Requires two keys: public and private

• Is faster than symmetric encryption

What does integrity in cryptography refer to?

• Keeping data secret

• Preventing unauthorized data modification

• Ensuring data availability

• Authenticating users

What is the main difference between algorithms and implementations in cryptography?

• Algorithms require a key, implementations do not.

• There is no difference.

• Algorithms are theoretical, implementations are practical.

• Implementations are always more secure than algorithms.