Cyber Security Cryptography 3

Question 1

What is the purpose of a Certificate Revocation List (CRL)?

Accepted Answer

Identify certificates that have been revoked before expiry

Answer

A CRL lists digital certificates that have been revoked before their expiration date, informing relying parties not to trust them.

Question 2

Which elliptic curve algorithm is commonly used for key agreement in modern TLS implementations?

Accepted Answer

ECDH (Elliptic Curve Diffie-Hellman)

Answer

ECDH provides key agreement using elliptic curve mathematics, offering strong security with shorter key lengths.

Question 3

What is steganography?

Accepted Answer

Hiding secret data within non-secret files or media

Answer

Steganography conceals secret information within ordinary files such as images, audio, or video.

Question 4

What does HMAC (Hash-based Message Authentication Code) provide?

Accepted Answer

Both message integrity and authenticity using a shared secret key

Answer

HMAC combines a cryptographic hash with a secret key to provide both data integrity and authentication.

Question 5

Which property of a cryptographic hash function ensures it is computationally infeasible to find the original input from its hash?

Accepted Answer

Preimage resistance

Answer

Preimage resistance means it is computationally infeasible to reverse a hash and recover the original input.

Cyber Security Practice Test