Introduction to Cryptography -
D334QUESTIONS AND
VERIFIED CORRECT
ANSWERS GRADED A+
[LATEST] 100% GUARANTEED
PASS
XOR the following
0101110101010111
1001100000111010
------------------ - CORRECT ANSWER-1100010101101101
asymmetric key-based encryption
-typical methods - CORRECT ANSWER-RSA
DSA
El Gamal
Symmetric key-based encryption
-Typical Methods - CORRECT ANSWER-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 ANSWER-RC2(40 bit key size)
RC5(Variable block size)
IDEA
DES
3DES
AES (Rijndael)
Blowfish
twofish
stream encryption - CORRECT ANSWER-RC4
Chacha
Rainbow Attack - CORRECT ANSWER-The method of knowing the mapping between the hashed
values and the original data
Dictionary-type attack - CORRECT ANSWER-a brute force analysis
∉ - CORRECT ANSWER-does not belong to
when an object is not in a set
∈ - CORRECT ANSWER-Belongs to
when an object is within a set
⊆ - CORRECT ANSWER-subset
,subset has fewer elements or equal to the set
A ∪ B - CORRECT ANSWER-union (objects that belong to set A or set B)
| - CORRECT ANSWER-such that
A ∩ B - CORRECT ANSWER-Intersection: in both A and B
Enigma Machine -Cypher 10 - CORRECT ANSWER-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 ANSWER-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 ANSWER-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 ANSWER-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 ANSWER-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 ANSWER-Encoding method, rather than a cipher, that works by
translating characters into sequences of dots (.) and dashes (-)
Playfair Cipher 4 - CORRECT ANSWER-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 ANSWER-Makes use of a grid and which maps the letters into numeric
values.
Apache-defined APR1 format - CORRECT ANSWER-addresses the problems of brute forcing an
MD5 hash, and basically iterates the hash value 1,000 times.
HMAC - CORRECT ANSWER-is a message authentication code (MAC) that can be used to verify
the integrity and authentication of the message. It involves hashing the message with a secret
key, and thus differs from standard hashing, which is purely a one-way function
Passwords which use a hashed value can be cracked - CORRECT ANSWER-as either with rainbow
tables or brute force.
One Time Passwords (OTP) - CORRECT ANSWER-This allows a new unique password to be
created for each instance, based on an initial seed
Timed one time password (TOTP) - CORRECT ANSWER-This allows for a new unique passcode to
be created for each instance, based on an initial seed and for a given time period.
D334QUESTIONS AND
VERIFIED CORRECT
ANSWERS GRADED A+
[LATEST] 100% GUARANTEED
PASS
XOR the following
0101110101010111
1001100000111010
------------------ - CORRECT ANSWER-1100010101101101
asymmetric key-based encryption
-typical methods - CORRECT ANSWER-RSA
DSA
El Gamal
Symmetric key-based encryption
-Typical Methods - CORRECT ANSWER-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 ANSWER-RC2(40 bit key size)
RC5(Variable block size)
IDEA
DES
3DES
AES (Rijndael)
Blowfish
twofish
stream encryption - CORRECT ANSWER-RC4
Chacha
Rainbow Attack - CORRECT ANSWER-The method of knowing the mapping between the hashed
values and the original data
Dictionary-type attack - CORRECT ANSWER-a brute force analysis
∉ - CORRECT ANSWER-does not belong to
when an object is not in a set
∈ - CORRECT ANSWER-Belongs to
when an object is within a set
⊆ - CORRECT ANSWER-subset
,subset has fewer elements or equal to the set
A ∪ B - CORRECT ANSWER-union (objects that belong to set A or set B)
| - CORRECT ANSWER-such that
A ∩ B - CORRECT ANSWER-Intersection: in both A and B
Enigma Machine -Cypher 10 - CORRECT ANSWER-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 ANSWER-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 ANSWER-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 ANSWER-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 ANSWER-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 ANSWER-Encoding method, rather than a cipher, that works by
translating characters into sequences of dots (.) and dashes (-)
Playfair Cipher 4 - CORRECT ANSWER-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 ANSWER-Makes use of a grid and which maps the letters into numeric
values.
Apache-defined APR1 format - CORRECT ANSWER-addresses the problems of brute forcing an
MD5 hash, and basically iterates the hash value 1,000 times.
HMAC - CORRECT ANSWER-is a message authentication code (MAC) that can be used to verify
the integrity and authentication of the message. It involves hashing the message with a secret
key, and thus differs from standard hashing, which is purely a one-way function
Passwords which use a hashed value can be cracked - CORRECT ANSWER-as either with rainbow
tables or brute force.
One Time Passwords (OTP) - CORRECT ANSWER-This allows a new unique password to be
created for each instance, based on an initial seed
Timed one time password (TOTP) - CORRECT ANSWER-This allows for a new unique passcode to
be created for each instance, based on an initial seed and for a given time period.
