SE Cryptography and PKI

Question 1

Which type of encryption uses the same key for both encryption and decryption?

Accepted Answer

Symmetric encryption

Answer

Asymmetric encryption

Answer

Hashing

Answer

Steganography

Question 2

What is the primary purpose of a Certificate Authority (CA) in a PKI?

Accepted Answer

Issue and sign digital certificates to verify identity

Answer

Generate passwords for users

Answer

Encrypt data in transit

Answer

Manage firewall rules

Question 3

Which algorithm is widely used for asymmetric key exchange and digital signatures in TLS certificates?

Accepted Answer

RSA

Answer

AES-256

Answer

SHA-256

Answer

HMAC

Question 4

A digital signature provides which two security properties?

Accepted Answer

Authentication and non-repudiation

Answer

Confidentiality and availability

Answer

Integrity and confidentiality

Answer

Authorization and accounting

Question 5

What is the difference between a hash function and encryption?

Accepted Answer

Hashing is a one-way function with no decryption; encryption is reversible with a key

Answer

Hashing is reversible; encryption is not

Answer

Encryption is faster than hashing

Answer

Hashing uses public keys; encryption uses private keys

Question 6

What is a Certificate Revocation List (CRL) used for?

Accepted Answer

Publishing certificates that have been revoked before their expiry

Answer

Listing all issued certificates

Answer

Renewing expired certificates

Answer

Storing private keys