D 334 Pre-Assessment (Latest Update
) Introduction to Cryptography
Questions with Answers {Grade A} 100%
Correct (Verified Answers) - WGU
One-time pad cypher8 - correct answer Cypher Code mapping that is only used once.
Advantage: it is essentially unbreakable.
Disadvantage: it takes lots of work as you would have to generate the pad to be used,
each time.
Vigenere Cipher 7 - correct answer Polyalphabetic cipher that involves using a
different mapping, based on a keyword, for each character of the cipher. An
advantage of this type of cipher is that the same plaintext character is likely to be
coded to different mappings, depending on the position of the keyword, making
guessing more difficult.
Ceasar Cipher6 - correct answer Mono-alphabetic substitution cipher known as "shift"
cipher. Involves plaintext being replaced by a letter some fixed number of positions
down the alphabet. i.e., a Caesar Cipher using a shift of +3 would mean a plaintext
letter A would result in a ciphertext letter D (a shift of three positions to the right in
the alphabet)
Morse Code cipher 5 - correct answer Encoding method, rather than a cipher, that
works by translating characters into sequences of dots (.) and dashes (-)
, D 334 Pre-Assessment (Latest Update
) Introduction to Cryptography
Questions with Answers {Grade A} 100%
Correct (Verified Answers) - WGU
Playfair Cipher 4 - correct answer 5 × 5 matrix containing the alphabet less the letter
J. Cipher/decipher process consists of a set of rules outlining use of column and row
combinations.
BIFID Cipher 3 - correct answer Makes use of a grid and which maps the letters into
numeric values.
Rail Code Cipher 2 - correct answer Employs a method to scramble text by writing it
in a sequence across a number of rails.
Pig Pen Cipher 1 - correct answer Mono- alphabetic substitution cipher that makes
use of mapping plaintext characters to graphical characters rather than to alphabetic
ones. i.e. A=(pick a symbol), vs A=(pick a letter). Disadvantage: once the mapping is
known, it is difficult to keep the message secret.
Encryption - correct answer in simplest terms is changing plaintext into ciphertext
Decryption - correct answer The process of converting a ciphertext into plaintext.
AESCrypt - correct answer Encrypt individual files and encrypt full disks with options
such as Bitlocker and FileVault
, D 334 Pre-Assessment (Latest Update
) Introduction to Cryptography
Questions with Answers {Grade A} 100%
Correct (Verified Answers) - WGU
Mono-alphabetic - correct answer c code or substitution is where a single mapping
from our alphabet to a cipher alphabet is created. Many early cryptosystems used
this.
Polyalphabetic - correct answer refers to the mapping of our alphabet to a number of
cipher alphabets. This approach added a bit of complexity to early cryptosystems.
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
, D 334 Pre-Assessment (Latest Update
) Introduction to Cryptography
Questions with Answers {Grade A} 100%
Correct (Verified Answers) - WGU
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
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
) Introduction to Cryptography
Questions with Answers {Grade A} 100%
Correct (Verified Answers) - WGU
One-time pad cypher8 - correct answer Cypher Code mapping that is only used once.
Advantage: it is essentially unbreakable.
Disadvantage: it takes lots of work as you would have to generate the pad to be used,
each time.
Vigenere Cipher 7 - correct answer Polyalphabetic cipher that involves using a
different mapping, based on a keyword, for each character of the cipher. An
advantage of this type of cipher is that the same plaintext character is likely to be
coded to different mappings, depending on the position of the keyword, making
guessing more difficult.
Ceasar Cipher6 - correct answer Mono-alphabetic substitution cipher known as "shift"
cipher. Involves plaintext being replaced by a letter some fixed number of positions
down the alphabet. i.e., a Caesar Cipher using a shift of +3 would mean a plaintext
letter A would result in a ciphertext letter D (a shift of three positions to the right in
the alphabet)
Morse Code cipher 5 - correct answer Encoding method, rather than a cipher, that
works by translating characters into sequences of dots (.) and dashes (-)
, D 334 Pre-Assessment (Latest Update
) Introduction to Cryptography
Questions with Answers {Grade A} 100%
Correct (Verified Answers) - WGU
Playfair Cipher 4 - correct answer 5 × 5 matrix containing the alphabet less the letter
J. Cipher/decipher process consists of a set of rules outlining use of column and row
combinations.
BIFID Cipher 3 - correct answer Makes use of a grid and which maps the letters into
numeric values.
Rail Code Cipher 2 - correct answer Employs a method to scramble text by writing it
in a sequence across a number of rails.
Pig Pen Cipher 1 - correct answer Mono- alphabetic substitution cipher that makes
use of mapping plaintext characters to graphical characters rather than to alphabetic
ones. i.e. A=(pick a symbol), vs A=(pick a letter). Disadvantage: once the mapping is
known, it is difficult to keep the message secret.
Encryption - correct answer in simplest terms is changing plaintext into ciphertext
Decryption - correct answer The process of converting a ciphertext into plaintext.
AESCrypt - correct answer Encrypt individual files and encrypt full disks with options
such as Bitlocker and FileVault
, D 334 Pre-Assessment (Latest Update
) Introduction to Cryptography
Questions with Answers {Grade A} 100%
Correct (Verified Answers) - WGU
Mono-alphabetic - correct answer c code or substitution is where a single mapping
from our alphabet to a cipher alphabet is created. Many early cryptosystems used
this.
Polyalphabetic - correct answer refers to the mapping of our alphabet to a number of
cipher alphabets. This approach added a bit of complexity to early cryptosystems.
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
, D 334 Pre-Assessment (Latest Update
) Introduction to Cryptography
Questions with Answers {Grade A} 100%
Correct (Verified Answers) - WGU
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
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
