Introduction to Cryptography - D334 || 100% Valid Solutions.
XOR the following
0101110101010111
1001100000111010
------------------ correct answers 1100010101101101
asymmetric key-based encryption
-typical methods correct answers RSA
DSA
El Gamal
Symmetric key-based encryption
-Typical Methods correct answers RC2- 40 bit key size 64 bit block
RC4- (Stream Cipher)- Used in SSL and WEP
RC5- (Variable Key size, 32, 64, or 128 bit block size)
AES- (128, 192 or 256 bit key size, 128 bit block size)
DES- (56 bit key size. 64 bit Block size)
3DES- (112 bit key size, 64 bit block size)
Block Encryption correct answers RC2(40 bit key size)
RC5(Variable block size)
IDEA
DES
3DES
AES (Rijndael)
Blowfish
twofish
,stream encryption correct answers RC4
Chacha
Rainbow Attack correct answers The method of knowing the mapping between the hashed values
and the original data
Dictionary-type attack correct answers a brute force analysis
∉ correct answers does not belong to
when an object is not in a set
∈ correct answers Belongs to
when an object is within a set
⊆ correct answers subset
subset has fewer elements or equal to the set
A ∪ B correct answers union (objects that belong to set A or set B)
| correct answers such that
A ∩ B correct answers Intersection: in both A and B
Enigma Machine -Cypher 10 correct answers Used a polyalphabetic substitution cipher, which
did not repeat within a reasonable time period, along with a secret key. For the cracking of the
Enigma cipher, the challenge was thus to determine both the algorithm used and the key.
Enigma's main weakness, though, was that none of the plain text letters could be ciphered as
itself.
, Four-square cipher9 correct answers Uses four 5 × 5 matrices arranged in a square, are where
each matrix contains 25 letters for encoding and decoding operations.
One-time pad cypher8 correct answers 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 answers 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 answers 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 answers Encoding method, rather than a cipher, that works by
translating characters into sequences of dots (.) and dashes (-)
Playfair Cipher 4 correct answers 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 answers Makes use of a grid and which maps the letters into numeric
values.
Rail Code Cipher 2 correct answers Employs a method to scramble text by writing it in a
sequence across a number of rails.
XOR the following
0101110101010111
1001100000111010
------------------ correct answers 1100010101101101
asymmetric key-based encryption
-typical methods correct answers RSA
DSA
El Gamal
Symmetric key-based encryption
-Typical Methods correct answers RC2- 40 bit key size 64 bit block
RC4- (Stream Cipher)- Used in SSL and WEP
RC5- (Variable Key size, 32, 64, or 128 bit block size)
AES- (128, 192 or 256 bit key size, 128 bit block size)
DES- (56 bit key size. 64 bit Block size)
3DES- (112 bit key size, 64 bit block size)
Block Encryption correct answers RC2(40 bit key size)
RC5(Variable block size)
IDEA
DES
3DES
AES (Rijndael)
Blowfish
twofish
,stream encryption correct answers RC4
Chacha
Rainbow Attack correct answers The method of knowing the mapping between the hashed values
and the original data
Dictionary-type attack correct answers a brute force analysis
∉ correct answers does not belong to
when an object is not in a set
∈ correct answers Belongs to
when an object is within a set
⊆ correct answers subset
subset has fewer elements or equal to the set
A ∪ B correct answers union (objects that belong to set A or set B)
| correct answers such that
A ∩ B correct answers Intersection: in both A and B
Enigma Machine -Cypher 10 correct answers Used a polyalphabetic substitution cipher, which
did not repeat within a reasonable time period, along with a secret key. For the cracking of the
Enigma cipher, the challenge was thus to determine both the algorithm used and the key.
Enigma's main weakness, though, was that none of the plain text letters could be ciphered as
itself.
, Four-square cipher9 correct answers Uses four 5 × 5 matrices arranged in a square, are where
each matrix contains 25 letters for encoding and decoding operations.
One-time pad cypher8 correct answers 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 answers 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 answers 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 answers Encoding method, rather than a cipher, that works by
translating characters into sequences of dots (.) and dashes (-)
Playfair Cipher 4 correct answers 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 answers Makes use of a grid and which maps the letters into numeric
values.
Rail Code Cipher 2 correct answers Employs a method to scramble text by writing it in a
sequence across a number of rails.
