Cyber Security Cryptography

Question 1

What is the key difference between symmetric and asymmetric encryption?

Accepted Answer

Symmetric uses one shared key; asymmetric uses a public/private key pair

Answer

Symmetric encryption uses one shared key for both encryption and decryption, while asymmetric uses a public/private key pair.

Question 2

Which hashing algorithm produces a 256-bit digest and is commonly used in digital signatures and certificates?

Accepted Answer

SHA-256

Answer

SHA-256 produces a 256-bit hash and is widely used in TLS certificates and digital signatures.

Question 3

What is the purpose of a digital signature?

Accepted Answer

Verify the authenticity and integrity of a message

Answer

A digital signature verifies that a message came from the claimed sender and has not been altered.

Question 4

Which encryption standard replaced DES and is the current US federal standard for symmetric encryption?

Accepted Answer

AES

Answer

AES (Advanced Encryption Standard) replaced DES in 2001 and is the current NIST-approved symmetric cipher.

Question 5

What is a collision in the context of cryptographic hash functions?

Accepted Answer

When two different inputs produce the same hash output

Answer

A hash collision occurs when two different inputs produce the same hash digest, undermining integrity guarantees.

Cyber Security Practice Test