Introduction to Cryptography -
C839 with 100% correct
answers
Cryptography - answer science of altering communication so that it
cannot be 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
,Playfair Cipher - answer uses a 5 by 5 table containing a keyword or
phrase encrypts two letters rather than one.
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
Symmetric algorithm encryption - answer C = E[k,p]
, Symmetric algorithm decryption - answer P = D[k,c]
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
1101
1001
C839 with 100% correct
answers
Cryptography - answer science of altering communication so that it
cannot be 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
,Playfair Cipher - answer uses a 5 by 5 table containing a keyword or
phrase encrypts two letters rather than one.
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
Symmetric algorithm encryption - answer C = E[k,p]
, Symmetric algorithm decryption - answer P = D[k,c]
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
1101
1001