WGU C839 INTRO TO CRYPTOGRAPHY OA PREPARATION COMPLETE ACTUAL QUESTIONS AND CORRECT DETAILED ANSWERS (CORRECT VERIFIED ANSWERS) LATEST UPDATED VERSION

WGU C839 Introduction to Cryptography - (EC-Council CES)
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1. CrypTool: Software which allows encryption of text using historic algorithms
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2. The Enigma Machine: In World War II the Germans made use of an electro-me-
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chanical rotor based cipher Known as The Enigma Machine.
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Allied cipher machines used in WWII included the British TypeX and the AmericanSI
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GABA.


3. The ADFGVX Cipher: invented by Colonel Fritz Nebel in 1918.
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The key for this algorithm is a six-by-six square of letters, used to encode a 36-
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letteralphabet.
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4. The Playfair Cipher: invented in 1854 by Charles Wheatstone.
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The Playfair cipher uses a five-by-five table containing a keyword or key phrase.
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5. Breaking the Vigene k k




re Ciph:eIrn 1863, Friedrich Kasiski was the first personto publish a successful gen
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eral attack on the Vigene
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,6. The Vigene k re Ciph:eT
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alphabet substitution cipher. invented in 1553 by Giovan Battista Bellaso. Uses a se
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ries ofdifferent Caesar ciphers based on the letters of a keyword.
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7. The Cipher Disk: The cipher disk was invented by Leon Alberti in 1466. eachtim
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e you turned the disk, you used a new cipher. It was literally a disk you turnedto encr
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ypt plaintext.
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8. Multi-
Alphabet Substitution: Use of multiple substitution alphabets.Example:
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Cipher Disk, Vigenere Cipher, Enigma Machine
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9. Scytale: This was a cylinder tool used by the Greeks, and is often specificallyattr
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ibuted to the Spartans. Physical cylinder that was used to encrypt messages.
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10. ROT13 Cipher: It is essentially the Caesar cipher always using a rotation orshi
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ft of 13 characters.
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11. The ATBASH Cipher: Hebrew scribes copying religious texts used this cipher.su
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bstitutes the first letter of the alphabet for the
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last, and the second letter for the second-to-the-last, etc.
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12. The Caesar Cipher: You can choose to shift any number of letters, either leftor r
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ight. If you choose to shift two to
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the right, that would be a +2; if you choose to shift four to the left, that would be a
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-4.

13. Mono-Alphabet Substitution: These algorithms k k k


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,simply substitute one character of cipher text for each character of plain text.
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, Examples: Atbash Cipher, Caesar Cipher, Rot13 k k k k k




14. Symmetric Cryptography: It is simply any algorithm where the key used tode k k k k k k k k k k k k




crypt a message is the same key used to encrypt.
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15. Diffusion: Changes to one character in the plain text affect multiple charactersin t
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he cipher text.
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16. Confusion: Confusion attempts to make the relationship between the statisti- k k k k k k k k k




cal frequencies of the cipher text and the actual key as complex as possible. Thisocc
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urs by using a complex substitution algorithm.
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17. Avalanche: a small change yields large effects in the output, This is Fiestel'svar
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iation on Claude Shannon's concept of diffusion.
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18. Kerckhoffs's Principle: This principle states that a cryptosystem should bese k k k k k k k k k k




cure even if everything about the system, except the key, is publicly known.
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19. Substitution: Substitution is changing some part of the plaintext for somem k k k k k k k k k k k




atching part of the Cipher Text. k k k k k




20. Transposition: Transposition is the swapping of blocks of ciphertext. k k k k k k k k




21. binary numbers: there are three operations not found in normal math:A
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ND, OR, and XOR operations.
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22. Binary AND: If both numbers have a one in both places, then the resultantnu
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mber is a one. k k k




1101
1001

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