WGU C839 OBJECTIVE ASSESSMENT 2 LATEST VERSIONS (VERSION A & B) 2023-
2024/2024-2025 /WGU C839 INTRODUCTION TO CRYPTOGRAPHY OA ACTUAL
EXAM / COMPLETE REAL EXAM QUESTIONS AND CORRECT ANSWERS
(VERIFIED ANSWERS ) ALREADY GRADED A+.
Which encryption standard uses the same key to encrypt and decrypt
messages? - ANSWER-Symmetric
Which algorithm is designated as a Type 2 product by the National
Security Agency (NSA)? - ANSWER-Skipjack
What is the most commonly used format for certificates? - ANSWER-
X.509 v3
What is referenced to determine if a certificate has been revoked? -
ANSWER-Certificate revocation list (CRL)
What needs to be installed on end users' computers to allow them to
trust applications that have been digitally signed by the developer? -
ANSWER-Sender's public key
Which type of certificate must be certified by an authority to verify it
with other participants? - ANSWER-Public Certificate
,What is an attribute of the Rivest Cipher 4 (RC4) algorithm? -
ANSWER-It requires a unique nonce.
Which mode generates the key stream with a nonce and incrementing
value? - ANSWER-Counter (CTR)
Which mode is a stream algorithm that concatenates an incrementing
value with a nonce? - ANSWER-Counter (CTR)
Which key would an administrator use to encrypt data so only the
CEO can decrypt it? - ANSWER-CEO's public key
What is the result of a hash function? - ANSWER-Digest
What is used to efficiently encrypt large files? - ANSWER-Symmetric
encryption
An administrator needs to encrypt the following word with the Atbash
cipher: security What is the correct ciphertext? - ANSWER-hvxfirgb
Which cryptographic algorithm has a 128-bit hash size? - ANSWER-
Message Digest Algorithm 5 (MD5)
Which characteristic makes a hashing function suitable for use in
signature schemes? - ANSWER-Collision resistance
,Which attribute of a hashing function makes a birthday attack
possible? - ANSWER-Partial-message collision
Which hash algorithm produces a 160-bit output value? - ANSWER-
SHA-1
What does cipher block chaining (CBC) use with the key to encrypt
subsequent blocks of plaintext? - ANSWER-Previous generated
ciphertext
Which mode produces the same ciphertext from two identical
plaintext blocks? - ANSWER-Electronic codebook (ECB)
Which encryption mode is least secure? - ANSWER-Electronic
codebook (ECB)
What is the mathematical formula used for symmetric decryption? -
ANSWER-P = E (K,C)
Which algorithm relies on factoring the product of large prime
numbers? - ANSWER-Rivest-Shamir-Adleman
Which encryption technology is a serial combination of hashing, data
compression, symmetric-key cryptography, and public key
infrastructure (PKI) and can be used for encrypting texts, emails, files,
and directories or for full disk encryption? - ANSWER-Pretty Good
Privacy (PGP)
, Which concept stipulates that algorithms should be openly shared
and scrutinized, but keys must be absolutely secured? - ANSWER-
Kerckhoffs's principle
Which encryption process minimizes known plaintext attacks against
Advanced Encryption Standard (AES)? - ANSWER-Randomizing the
initialization vector
What prevents a rainbow table attack during the encryption process?
- ANSWER-Salting
Which factor increases the required number of attempts in a
bruteforce attack? - ANSWER-Larger key size
What is a vulnerability of the Data Encryption Standard (DES)? -
ANSWER-Key length is too short.
Which block size does the Advanced Encryption Standard (AES) use?
- ANSWER-128
Which block algorithm includes a provision for the decryption key
kept in a key escrow? - ANSWER-Skipjack
What is the result of A|B and B|C? - ANSWER-A|C
How is X mod N if N = PQ represented in number theory? - ANSWER-(
2024/2024-2025 /WGU C839 INTRODUCTION TO CRYPTOGRAPHY OA ACTUAL
EXAM / COMPLETE REAL EXAM QUESTIONS AND CORRECT ANSWERS
(VERIFIED ANSWERS ) ALREADY GRADED A+.
Which encryption standard uses the same key to encrypt and decrypt
messages? - ANSWER-Symmetric
Which algorithm is designated as a Type 2 product by the National
Security Agency (NSA)? - ANSWER-Skipjack
What is the most commonly used format for certificates? - ANSWER-
X.509 v3
What is referenced to determine if a certificate has been revoked? -
ANSWER-Certificate revocation list (CRL)
What needs to be installed on end users' computers to allow them to
trust applications that have been digitally signed by the developer? -
ANSWER-Sender's public key
Which type of certificate must be certified by an authority to verify it
with other participants? - ANSWER-Public Certificate
,What is an attribute of the Rivest Cipher 4 (RC4) algorithm? -
ANSWER-It requires a unique nonce.
Which mode generates the key stream with a nonce and incrementing
value? - ANSWER-Counter (CTR)
Which mode is a stream algorithm that concatenates an incrementing
value with a nonce? - ANSWER-Counter (CTR)
Which key would an administrator use to encrypt data so only the
CEO can decrypt it? - ANSWER-CEO's public key
What is the result of a hash function? - ANSWER-Digest
What is used to efficiently encrypt large files? - ANSWER-Symmetric
encryption
An administrator needs to encrypt the following word with the Atbash
cipher: security What is the correct ciphertext? - ANSWER-hvxfirgb
Which cryptographic algorithm has a 128-bit hash size? - ANSWER-
Message Digest Algorithm 5 (MD5)
Which characteristic makes a hashing function suitable for use in
signature schemes? - ANSWER-Collision resistance
,Which attribute of a hashing function makes a birthday attack
possible? - ANSWER-Partial-message collision
Which hash algorithm produces a 160-bit output value? - ANSWER-
SHA-1
What does cipher block chaining (CBC) use with the key to encrypt
subsequent blocks of plaintext? - ANSWER-Previous generated
ciphertext
Which mode produces the same ciphertext from two identical
plaintext blocks? - ANSWER-Electronic codebook (ECB)
Which encryption mode is least secure? - ANSWER-Electronic
codebook (ECB)
What is the mathematical formula used for symmetric decryption? -
ANSWER-P = E (K,C)
Which algorithm relies on factoring the product of large prime
numbers? - ANSWER-Rivest-Shamir-Adleman
Which encryption technology is a serial combination of hashing, data
compression, symmetric-key cryptography, and public key
infrastructure (PKI) and can be used for encrypting texts, emails, files,
and directories or for full disk encryption? - ANSWER-Pretty Good
Privacy (PGP)
, Which concept stipulates that algorithms should be openly shared
and scrutinized, but keys must be absolutely secured? - ANSWER-
Kerckhoffs's principle
Which encryption process minimizes known plaintext attacks against
Advanced Encryption Standard (AES)? - ANSWER-Randomizing the
initialization vector
What prevents a rainbow table attack during the encryption process?
- ANSWER-Salting
Which factor increases the required number of attempts in a
bruteforce attack? - ANSWER-Larger key size
What is a vulnerability of the Data Encryption Standard (DES)? -
ANSWER-Key length is too short.
Which block size does the Advanced Encryption Standard (AES) use?
- ANSWER-128
Which block algorithm includes a provision for the decryption key
kept in a key escrow? - ANSWER-Skipjack
What is the result of A|B and B|C? - ANSWER-A|C
How is X mod N if N = PQ represented in number theory? - ANSWER-(
