D 334 Pre-Assessment – Practice Questions and Exam Preparation Material

D 334 Pre-Assessment (Latest Update
) Introduction to Cryptography
Questions with Answers {Grade A} 100%
Correct (Verified Answers) - WGU
One-time pad - correct answer is considered to be unbreakable since it only uses its

cipher code once.


Pseudo-Random Number Generators (PRNGs) - correct answer This method repeats

the random numbers after a given time (periodic). They are fast and are also
deterministic and are useful in producing a repeatable set of random numbers.



Frequency Analysis - correct answer is cipher cracking methodology that involves
identifying patterns and variations in the probability of codes. i.e. a three-letter

ciphered text combination spotted at the beginning of a string too often could tip us
off that those three letters correlate the letters THE in the English alphabet.



True Random Number Generators (TRNGs) - correct answer This method generates a
true random number and uses some form of random process. One approach is to
monitor the movements of a mouse pointer on a screen or from the pauses between
keystrokes. Overall, the method is generally slow, especially if it involves human

interaction, but is non-deterministic and aperiodic.


Entropy - correct answer measures level of unpredictability; in encryption relates to
the degree of uncertainty of the encryption process.



ASCII - correct answer 8-bit values, up to 256 characters

, D 334 Pre-Assessment (Latest Update
) Introduction to Cryptography
Questions with Answers {Grade A} 100%
Correct (Verified Answers) - WGU

UTF-16 - correct answer 16- bit values, up to 65,536 characters


Hardware vs Software encryption - correct answer Hardware encryption is more

efficient than software encryption.


XOR the following

0101110101010111

1001100000111010
-------------------- correct answer 1100010101101101



asymmetric key-based encryption
-typical methods - correct answer RSA
DSA

El Gamal


Symmetric key-based encryption
-Typical Methods - correct answer RC2- 40 bit key size 64 bit block
RC4- (Stream Cipher)- Used in SSL and WEP

RC5- (Variable Key size, 32, 64, or 128 bit block size)

AES- (128, 192 or 256 bit key size, 128 bit block size)
DES- (56 bit key size. 64 bit Block size)

, D 334 Pre-Assessment (Latest Update
) Introduction to Cryptography
Questions with Answers {Grade A} 100%
Correct (Verified Answers) - WGU
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