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WGU C839 Introduction to Cryptography - (EC-Council CES)
1.CrypTool: Software which allows encryption of text using historic
algorithms
2.The Enigma Machine: In World War II the Germans made use of an
electro-me- chanical rotor based cipher Known as The Enigma Machine.Allied cipher machines used in WWII included the British TypeX and the American SIGABA.
3.The ADFGVX Cipher: invented by Colonel Fritz Nebel in 1918.
The key for this algorithm is a six-by-six square of letters, used to encode a 36-letter alphabet.
4.The Playfair Cipher: invented in 1854 by Charles Wheatstone.
The Playfair cipher uses a five-by-five table containing a keyword or key phrase. 1 / 4
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5.Breaking the Vigenere Ciph:eIrn 1863, Friedrich Kasiski was the first
person to publish a successful general attack on the Vigenere Cipher
6.The Vigenere Ciph:eTr his is perhaps the most widely known multi-
alphabet substitution cipher. invented in 1553 by Giovan Battista Bellaso. Uses a series of different Caesar ciphers based on the letters of a keyword.
7.The Cipher Disk: The cipher disk was invented by Leon Alberti in
- each time you turned the disk, you used a new cipher. It was
literally a disk you turned to encrypt plaintext.
8.Multi-Alphabet Substitution: Use of multiple substitution
alphabets. Example:Cipher Disk, Vigenere Cipher, Enigma
Machine
9.Scytale: This was a cylinder tool used by the Greeks, and is often
specifically attributed to the Spartans. Physical cylinder that was used to encrypt messages.
10.ROT13 Cipher: It is essentially the Caesar cipher always using a
rotation or shift of 13 characters.
11.The ATBASH Cipher: Hebrew scribes copying religious texts used
this cipher. substitutes the first letter of the alphabet for the last, and the second letter for the second-to-the-last, etc. 2 / 4
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12.The Caesar Cipher: You can choose to shift any number of letters,
either left or right. If you choose to shift two to the right, that would be a +2; if you choose to shift four to the left, that would be a -4.
13.Mono-Alphabet Substitution: These algorithms
simply substitute one character of cipher text for each character of plain text. 3 / 4
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Examples: Atbash Cipher, Caesar Cipher, Rot13
14.Symmetric Cryptography: It is simply any algorithm where the key
used to decrypt a message is the same key used to encrypt.
15.Diffusion: Changes to one character in the plain text affect multiple
characters in the cipher text.
16.Confusion: Confusion attempts to make the relationship between
the statisti- cal frequencies of the cipher text and the actual key as complex as possible. This occurs by using a complex substitution algorithm.
17.Avalanche: a small change yields large effects in the output, This is
Fiestel's variation on Claude Shannon's concept of diffusion.
18.Kerckhoffs's Principle: This principle states that a cryptosystem
should be secure even if everything about the system, except the key, is publicly known.
19.Substitution: Substitution is changing some part of the plaintext
for some matching part of the Cipher Text.
20.Transposition: Transposition is the swapping of blocks of ciphertext.
21.binary numbers: there are three operations not found in
normal math: AND, OR, and XOR operations.
22.Binary AND: If both numbers have a one in both places, then the
resultant number is a one.
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