WGU C839 INTRODUCTION TO CRYPTOGRAPHY EXAM ACTUAL EXAM COMPLETE QUESTIONS AND CORRECT DETAILED ANSWERS

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WGU C839 INTRODUCTION TO CRYPTOGRAPHY
EXAM ACTUAL EXAM COMPLETE QUESTIONS AND
可以！请告诉我您需要写什么主题的中文作文，是写故事、议
CORRECT DETAILED ANSWERS
论文、记叙文，还是其他类型？另外，作文的字数要求是多少
Cryptography - (answer)science of altering communication so that it cannot be
呢？
understood without having the key


Mono-Alphabet Substitution - (answer)algorithms simply substitute one
character of cipher text for each character of plain text.


Caesar Cipher - (answer)choose a number by which to shift each letter of a
text.


ATBASH Cipher - (answer)Hebrew code substitutes first letter of alphabet for
last, second letter for the second-to-the-last


ROT13 Cipher - (answer)characters rotated 13 characters


Scytale - (answer)Greek, written across leather, and wrapped around physical
cylinder


Substitution Weaknesses - (answer)easy to break, preserve underlying letter
and word frequency


Multi-Alphabet Substitution - (answer)use multiple alphabets,


Cipher Disk - (answer)Leon Alberti in 1466, polyalphabetic;


Vigenère Cipher - (answer)1553 by Giovan Battista; until early 1900s, multi-
alphabet, 26X26

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Playfair Cipher - (answer)uses a 5 by 5 table containing a keyword or phrase
encrypts可以！请告诉我您需要写什么主题的中文作文，是写故事、议
two letters rather than one.
论文、记叙文，还是其他类型？另外，作文的字数要求是多少
呢？
ADFGVX - (answer)36-letter alphabet; six-by-six square of letters,


Enigma Machine - (answer)Used In World War II the Germans;
electromechanical rotor-based cipher system;


SIGABA - (answer)WWII American similar to the Enigma machine, but with
improvements and more security.


TypeX - (answer)WWII British similar to the Enigma machine, but with
improvements and more security.


Symmetric Cryptography - (answer)same key used to decrypt and to encrypt;
faster then asymmetric


Diffusion - (answer)changes to one character in the plaintext affect multiple
characters in the ciphertext


Confusion - (answer)attempts to make the relationship between the statistical
frequencies of the cipher text and the actual key as complex as possible


Avalanche - (answer)small change yields large effects in the output


Kerckhoffs's Principle - (answer)algorithm is publically known, only the key or
keys are kept secret

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Symmetric algorithm encryption - (answer)C = E[k,p]


可以！请告诉我您需要写什么主题的中文作文，是写故事、议
Symmetric algorithm decryption - (answer)P = D[k,c]
论文、记叙文，还是其他类型？另外，作文的字数要求是多少
呢？
Substitution - (answer)changing some part of the plaintext for some matching
part of ciphertext.


Transposition - (answer)swapping of blocks of ciphertext


Binary AND - (answer)take two binary numbers and compare them; both
numbers have a one in both places, then the result in one. If not, result zero


1101
1001
-----
1001


Binary OR - (answer)take two binary numbers and compare them; a one in
either or both numbers = one; If not, = zero,


1101
1001
-----
1101


Binary XOR - (answer)take two binary numbers and compare them; one in a
given place, and not both at that place = 1 otherwise = 0