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WGU C839 OBJECTIVE ASSESSMENT FINAL EXAM NEWEST
2025/2026 NEWEST ACTUAL EXAM WITH COMPLETE
QUESTIONS AND VERIFIED ANSWERS |ALREADY GRADED
A+|
Which of the following modes can be used to turn a block cipher
into a stream cipher? - ANSWER-Output feedback (OFB) and
Counter Mode (CTR)
Online business transactions between companies - ANSWER-
Class 4 certificates
EFS is encryption for files while Bitlocker is used for full disk
encryption - ANSWER-EFS vs. Bitlocker
Cryptanalysis attack that exploits vulnerabilities within the
algorithm structure. - ANSWER-Analytic attack
Open-community and standardized version of SSL
but TLS is more extensible and is backward compatible with SSL.
- ANSWER-Transport-Layer Security (TLS)
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Uses a block size of 128 bits and key sizes up to 256 bits. It is a
Feistel cipher. Designed by Bruce Schneier, John Kelsey, Doug
Whiting, David Wagner, Chris Hall, and Niels Ferguson. -
ANSWER-Twofish
160 bit hash - ANSWER-SHA-1
Cryptographic attack that exploits the mathematics behind the
birthday problem in the probability theory forces collisions within
hashing functions. - ANSWER-Birthday attack
A process that puts a message into the least significant bits of a
binary file is called what? - ANSWER-Steganography
Cryptanalysis attack that tries to uncover a mathematical problem
from two different ends. - ANSWER-Meet-in-the-middle attack
Asymmetric encryption method developed in 1984. It is used in
PGP implementations and GNU Privacy Guard Software.
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Consists of 3 parts: key generator, encryption algorithm, and
decryption algorithm. - ANSWER-El Gamal
A combination of the ISAKMP and OAKLEY protocols. -
ANSWER-Internet Key Exchange (IKE)
The payload of the message is protected - ANSWER-Transport
mode
What did WPA replace RC4 with? - ANSWER-TKIP (Temporal
Key Integrity Protocol)
N denotes natural numbers. These are also sometimes called the
counting numbers. They are 1, 2, 3, etc.
Z denotes the integers. These are whole numbers such as -1, 0,
1, 2, etc. Basically, this set is the natural numbers combined with
zero and the negative numbers.
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Q denotes rational numbers (or the ratios of integers). They are
any number that can be expressed as a ratio of two integers.
Examples are 3/2, 17/4, and 1/5.
R denotes real numbers. This includes the rational number as
well as numbers that cannot be expressed as a ratio of two
integers, such as 2/3.
i denotes imaginary numbers. These are numbers whose square
is a negative. For example, √-1 = 1i. - ANSWER-Explain the
number groupings: N, Z, Q, R, i
An encryption function for fixed-size blocks of data. The current
generation has a block size of 128 bits (16 bytes). - ANSWER-
block cipher
To encrypt with a block cipher, we need a ___________. -
ANSWER-secret key
WGU C839 OBJECTIVE ASSESSMENT FINAL EXAM NEWEST
2025/2026 NEWEST ACTUAL EXAM WITH COMPLETE
QUESTIONS AND VERIFIED ANSWERS |ALREADY GRADED
A+|
Which of the following modes can be used to turn a block cipher
into a stream cipher? - ANSWER-Output feedback (OFB) and
Counter Mode (CTR)
Online business transactions between companies - ANSWER-
Class 4 certificates
EFS is encryption for files while Bitlocker is used for full disk
encryption - ANSWER-EFS vs. Bitlocker
Cryptanalysis attack that exploits vulnerabilities within the
algorithm structure. - ANSWER-Analytic attack
Open-community and standardized version of SSL
but TLS is more extensible and is backward compatible with SSL.
- ANSWER-Transport-Layer Security (TLS)
, Page |2
Uses a block size of 128 bits and key sizes up to 256 bits. It is a
Feistel cipher. Designed by Bruce Schneier, John Kelsey, Doug
Whiting, David Wagner, Chris Hall, and Niels Ferguson. -
ANSWER-Twofish
160 bit hash - ANSWER-SHA-1
Cryptographic attack that exploits the mathematics behind the
birthday problem in the probability theory forces collisions within
hashing functions. - ANSWER-Birthday attack
A process that puts a message into the least significant bits of a
binary file is called what? - ANSWER-Steganography
Cryptanalysis attack that tries to uncover a mathematical problem
from two different ends. - ANSWER-Meet-in-the-middle attack
Asymmetric encryption method developed in 1984. It is used in
PGP implementations and GNU Privacy Guard Software.
, Page |3
Consists of 3 parts: key generator, encryption algorithm, and
decryption algorithm. - ANSWER-El Gamal
A combination of the ISAKMP and OAKLEY protocols. -
ANSWER-Internet Key Exchange (IKE)
The payload of the message is protected - ANSWER-Transport
mode
What did WPA replace RC4 with? - ANSWER-TKIP (Temporal
Key Integrity Protocol)
N denotes natural numbers. These are also sometimes called the
counting numbers. They are 1, 2, 3, etc.
Z denotes the integers. These are whole numbers such as -1, 0,
1, 2, etc. Basically, this set is the natural numbers combined with
zero and the negative numbers.
, Page |4
Q denotes rational numbers (or the ratios of integers). They are
any number that can be expressed as a ratio of two integers.
Examples are 3/2, 17/4, and 1/5.
R denotes real numbers. This includes the rational number as
well as numbers that cannot be expressed as a ratio of two
integers, such as 2/3.
i denotes imaginary numbers. These are numbers whose square
is a negative. For example, √-1 = 1i. - ANSWER-Explain the
number groupings: N, Z, Q, R, i
An encryption function for fixed-size blocks of data. The current
generation has a block size of 128 bits (16 bytes). - ANSWER-
block cipher
To encrypt with a block cipher, we need a ___________. -
ANSWER-secret key
