WGU C839 OA EXAM 100+ REAL EXAM QUESTIONS AND CORRECT ANSW
(VERIFIED ANSWERS)|AGRADE
Study online at https://quizlet.com/_hj6w23
1. Which encryption standard uses the same key to encrypt and decrypt
messages?: Symmetric
2. Which algorithm is designated as a Type 2 product by the National Security
Agency (NSA)?: Skipjack
3. What is the most commonly used format for certificates?: X.509 v3
4. What is referenced to determine if a certificate has been revoked?: Certifi-
cate revocation list (CRL)
5. What needs to be installed on end users' computers to allow them to trust
applications that have been digitally signed by the developer?: Sender's public
key
6. Which type of certificate must be certified by an authority to verify it with
other participants?: Public Certificate
7. What is an attribute of the Rivest Cipher 4 (RC4) algorithm?: It requires a
unique nonce.
8. Which mode generates the key stream with a nonce and incrementing
value?: Counter (CTR)
9. Which mode is a stream algorithm that concatenates an incrementing value
with a nonce?: Counter (CTR)
10. Which key would an administrator use to encrypt data so only the CEO can
decrypt it?: CEO's public key
11. What is the result of a hash function?: Digest
12. What is used to efficiently encrypt large files?: Symmetric encryption
13. An administrator needs to encrypt the following word with the Atbash
cipher: security What is the correct ciphertext?: hvxfirgb
14. Which cryptographic algorithm has a 128-bit hash size?: Message Digest
Algorithm 5 (MD5)
15. Which characteristic makes a hashing function suitable for use in signa-
ture schemes?: Collision resistance
16. Which attribute of a hashing function makes a birthday attack possible?: -
Partial-message collision
17. Which hash algorithm produces a 160-bit output value?: SHA-1
18. What does cipher block chaining (CBC) use with the key to encrypt sub-
sequent blocks of plaintext?: Previous generated ciphertext
19. Which mode produces the same ciphertext from two identical plaintext
blocks?: Electronic codebook (ECB)
20. Which encryption mode is least secure?: Electronic codebook (ECB)
21. What is the mathematical formula used for symmetric decryption?: P = E
(K,C)
1/8
, WGU C839 OA EXAM 100+ REAL EXAM QUESTIONS AND CORRECT ANSW
(VERIFIED ANSWERS)|AGRADE
Study online at https://quizlet.com/_hj6w23
22. Which algorithm relies on factoring the product of large prime numbers?-
: Rivest-Shamir-Adleman
23. Which encryption technology is a serial combination of hashing, data com-
pression, symmetric-key cryptography, and public key infrastructure (PKI) and
can be used for encrypting texts, emails, files, and directories or for full disk
encryption?: Pretty Good Privacy (PGP)
24. Which concept stipulates that algorithms should be openly shared and
scrutinized, but keys must be absolutely secured?: Kerckhoffs's principle
25. Which encryption process minimizes known plaintext attacks against Ad-
vanced Encryption Standard (AES)?: Randomizing the initialization vector
26. What prevents a rainbow table attack during the encryption process?: Salt-
ing
27. Which factor increases the required number of attempts in a brute-force
attack?: Larger key size
28. What is a vulnerability of the Data Encryption Standard (DES)?: Key length
is too short.
29. Which block size does the Advanced Encryption Standard (AES) use?: 128
30. Which block algorithm includes a provision for the decryption key kept in
a key escrow?: Skipjack
31. What is the result of A|B and B|C?: A|C
32. How is X mod N if N = PQ represented in number theory?: ( X mod P, X mod
Q)
33. What is the outcome when using the binary AND function on 11011 and
10100?: 10000
34. Which mode does the Fortuna algorithm use to generate random num-
bers?: Counter (CTR)
35. What is a potential weakness of a pseudo-random number generator
(PRNG)?: Same state used more than once
36. Which key combination is used to decrypt and verify a digital signature?-
: Recipient's private key to decrypt and sender's public key to verify the signature
37. Which key is used to sign a message or a message digest?: Sender's private
key
38. Which key does the certificate authority (CA) use to digitally sign keys that
it issues?: Server's private key
39. What does an end user need to verify a Rivest-Shamir -Adleman (RSA)
digitally signed message?: Sender's public key
40. What is used when creating a digital signature, using public key infrastruc-
ture (PKI)?: The private key of the person creating the message
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(VERIFIED ANSWERS)|AGRADE
Study online at https://quizlet.com/_hj6w23
1. Which encryption standard uses the same key to encrypt and decrypt
messages?: Symmetric
2. Which algorithm is designated as a Type 2 product by the National Security
Agency (NSA)?: Skipjack
3. What is the most commonly used format for certificates?: X.509 v3
4. What is referenced to determine if a certificate has been revoked?: Certifi-
cate revocation list (CRL)
5. What needs to be installed on end users' computers to allow them to trust
applications that have been digitally signed by the developer?: Sender's public
key
6. Which type of certificate must be certified by an authority to verify it with
other participants?: Public Certificate
7. What is an attribute of the Rivest Cipher 4 (RC4) algorithm?: It requires a
unique nonce.
8. Which mode generates the key stream with a nonce and incrementing
value?: Counter (CTR)
9. Which mode is a stream algorithm that concatenates an incrementing value
with a nonce?: Counter (CTR)
10. Which key would an administrator use to encrypt data so only the CEO can
decrypt it?: CEO's public key
11. What is the result of a hash function?: Digest
12. What is used to efficiently encrypt large files?: Symmetric encryption
13. An administrator needs to encrypt the following word with the Atbash
cipher: security What is the correct ciphertext?: hvxfirgb
14. Which cryptographic algorithm has a 128-bit hash size?: Message Digest
Algorithm 5 (MD5)
15. Which characteristic makes a hashing function suitable for use in signa-
ture schemes?: Collision resistance
16. Which attribute of a hashing function makes a birthday attack possible?: -
Partial-message collision
17. Which hash algorithm produces a 160-bit output value?: SHA-1
18. What does cipher block chaining (CBC) use with the key to encrypt sub-
sequent blocks of plaintext?: Previous generated ciphertext
19. Which mode produces the same ciphertext from two identical plaintext
blocks?: Electronic codebook (ECB)
20. Which encryption mode is least secure?: Electronic codebook (ECB)
21. What is the mathematical formula used for symmetric decryption?: P = E
(K,C)
1/8
, WGU C839 OA EXAM 100+ REAL EXAM QUESTIONS AND CORRECT ANSW
(VERIFIED ANSWERS)|AGRADE
Study online at https://quizlet.com/_hj6w23
22. Which algorithm relies on factoring the product of large prime numbers?-
: Rivest-Shamir-Adleman
23. Which encryption technology is a serial combination of hashing, data com-
pression, symmetric-key cryptography, and public key infrastructure (PKI) and
can be used for encrypting texts, emails, files, and directories or for full disk
encryption?: Pretty Good Privacy (PGP)
24. Which concept stipulates that algorithms should be openly shared and
scrutinized, but keys must be absolutely secured?: Kerckhoffs's principle
25. Which encryption process minimizes known plaintext attacks against Ad-
vanced Encryption Standard (AES)?: Randomizing the initialization vector
26. What prevents a rainbow table attack during the encryption process?: Salt-
ing
27. Which factor increases the required number of attempts in a brute-force
attack?: Larger key size
28. What is a vulnerability of the Data Encryption Standard (DES)?: Key length
is too short.
29. Which block size does the Advanced Encryption Standard (AES) use?: 128
30. Which block algorithm includes a provision for the decryption key kept in
a key escrow?: Skipjack
31. What is the result of A|B and B|C?: A|C
32. How is X mod N if N = PQ represented in number theory?: ( X mod P, X mod
Q)
33. What is the outcome when using the binary AND function on 11011 and
10100?: 10000
34. Which mode does the Fortuna algorithm use to generate random num-
bers?: Counter (CTR)
35. What is a potential weakness of a pseudo-random number generator
(PRNG)?: Same state used more than once
36. Which key combination is used to decrypt and verify a digital signature?-
: Recipient's private key to decrypt and sender's public key to verify the signature
37. Which key is used to sign a message or a message digest?: Sender's private
key
38. Which key does the certificate authority (CA) use to digitally sign keys that
it issues?: Server's private key
39. What does an end user need to verify a Rivest-Shamir -Adleman (RSA)
digitally signed message?: Sender's public key
40. What is used when creating a digital signature, using public key infrastruc-
ture (PKI)?: The private key of the person creating the message
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