CCP CCP Cryptography & PKI 1

Question 1

Which cryptographic property ensures that a sender cannot later deny having sent a message?

Accepted Answer

Non-repudiation

Answer

Non-repudiation, typically achieved through digital signatures, provides cryptographic proof of origin that prevents a sender from denying their actions.

Question 2

What is the primary difference between symmetric and asymmetric encryption?

Accepted Answer

Symmetric uses one key for encryption and decryption; asymmetric uses a public/private key pair

Answer

Symmetric encryption uses a single shared secret key for both encryption and decryption, while asymmetric encryption uses a mathematically linked key pair — one public, one private.

Question 3

Which hashing algorithm is currently recommended by NIST for generating message digests due to its resistance to collision attacks?

Accepted Answer

SHA-256

Answer

SHA-256 (part of the SHA-2 family) is NIST-recommended for cryptographic hashing, as MD5 and SHA-1 have known collision vulnerabilities.

Question 4

In a Public Key Infrastructure (PKI), what is the role of a Certificate Authority (CA)?

Accepted Answer

To issue, sign, and revoke digital certificates that bind public keys to identities

Answer

A CA is a trusted third party that issues digitally signed certificates, binding a subject's identity to their public key and enabling other parties to trust that binding.

Question 5

What mechanism allows a relying party to check whether a digital certificate has been revoked before it reaches its expiration date?

Accepted Answer

Online Certificate Status Protocol (OCSP)

Answer

OCSP provides real-time certificate revocation status by querying an OCSP responder, offering a more efficient alternative to downloading full Certificate Revocation Lists (CRLs).

(CCP) Certified Cyber Professional Practice Test

(CCP) Certified Cyber Professional Practice Test

CCP CCP Cryptography & PKI 1