Cryptography questions with answers

Question: Which encryption process sends a digital certificate with the selected cipher for encrypted communications?

Answer Choices:
A. Client hello
B. Integrity check
C. Server hello
D. Forward secrecy

Answer: C – Server hello

Question: An organization needs to implement a method for allowing encrypted data to be processed without providing access to the plaintext. Which encryption should be used?

Answer Choices:
A. Session
B. Asymmetric
C. Homomorphic
D. Symmetric

Answer: C – Homomorphic

Question: How does public-key encryption guarantee only the recipient can decrypt an email?

Answer Choices:
A. The payload of the email is encrypted with the recipient’s private key.
B. The hash of the email is encrypted with the sender’s private key.
C. The hash of the email is encrypted with the sender’s public key.
D. The payload of the email is encrypted with the recipient’s public key.

Answer: D – The payload of the email is encrypted with the recipient’s public key.

Question: What is the correlation between the number of blocks in a blockchain and the mining reward in Bitcoin?

Answer Choices:
A. The length of a blockchain increases over time, but the mining reward remains the same.
B. The length of a blockchain remains the same, but the mining reward increases over time.
C. As the length of a blockchain increases, the mining reward decreases.
D. As the length of a blockchain increases, the mining reward increases.

Answer: C – As the length of a blockchain increases, the mining reward decreases.

Question: Which cryptographic operation has the fastest decryption process?

Answer Choices:
A. Hashing
B. Asymmetric
C. Padding
D. Symmetric

Answer: D – Symmetric

Question: A server is using RSA for encrypting and protecting the transmission of a session key. Which RSA key size is valid?

Answer Choices:
A. 56-bit
B. 112-bit
C. 128-bit
D. 2,048-bit

Answer: D – 2,048-bit

Question: Which number generator has different results given the same input data?

Answer Choices:
A. Sequence
B. Prime
C. True random
D. Pseudorandom

Answer: C – True random

Question: What are the three stages of the 3DES encryption algorithm?

Answer Choices:
A. Encryption with key1, encryption with key1, encryption with key2
B. Encryption with key1, encryption with key2, encryption with key1
C. Encryption with key1, decryption with key2, encryption with key1
D. Encryption with key1, encryption with key1, decryption with key2

Answer: C – Encryption with key1, decryption with key2, encryption with key1

Question: How many transformation rounds does AES use with a 256-bit key?

Answer Choices:
A. 10
B. 12
C. 14
D. 16

Answer: C – 14

Question: How often are transactions added to a blockchain?

Answer Choices:
A. Approximately every 10 minutes
B. Approximately every 30 minutes
C. Approximately every 1 hour
D. Approximately every 24 hours

Answer: A – Approximately every 10 minutes

Question: Which encryption mechanism implements tamper resistance for a message?

Answer Choices:
A. Server hello
B. Integrity check
C. Client hello
D. Forward secrecy

Answer: B – Integrity check

Question: Which cryptographic operation is computationally more process intensive?

Answer Choices:
A. Asymmetric
B. Padding
C. Hashing
D. Symmetric

Answer: A – Asymmetric

Question: How are limits managed for the number of bitcoins that can be created and stored in a blockchain?

Answer Choices:
A. Each person has a maximum number
B. Rewards for mining reduce over time
C. The total number of participants has been set
D. A maximum has been established per country

Answer: B – Rewards for mining reduce over time

Question: How does WEP continue to change ciphertext for duplicate information in each frame?

Answer Choices:
A. Salt is removed from the data.
B. Cyclic redundancy check is updated.
C. Initialization vector is incremented.
D. Temporal Key Integrity Protocol is enabled.

Answer: C – Initialization vector is incremented

Question: What should be used when large amounts of data need to be quickly encrypted and decrypted one bit at a time?

Answer Choices:
A. Symmetric block
B. Asymmetric public key
C. Asymmetric private key
D. Symmetric stream

Answer: D – Symmetric stream