Cryptography and Network Security Quiz3

What is the study of principles/methods of deciphering ciphertext without knowing the key?

• Cryptanalysis

• Steganography

• Cryptology

• Cryptography

What is the size of plaintext in AES algorithm?

• 512 bits

• 64 bits

• 256 bits

• 128 bits

What is the last step in DES encryption?

• Expansion Permutation

• Inverse Initial Permutation

• Final Permutation

• Key Generation

How many keys are required for two people to communicate via asymmetric cipher?

• 4

• 2

• 1

• 3

What is the Hill cipher?

• Stream cipher

• Transposition cipher

• Polygraphic substitution cipher

• Shift cipher

Who invented the Vernam Cipher?

• Alan Turing

• Gilbert Vernam

• Ron Rivest

• Whitfield Diffie

What is Columnar Transpositions?

• Rearrangement of characters into rows

• Rearrangement of characters into columns

• Rearrangement of characters into a grid

• Rearrangement of characters into a circle

Is it true that Hill Cipher could be easily broken using cryptanalysis techniques?

• Partially true

• Not mentioned

• True

• False

What is AES?

• A slow algorithm

• A symmetric block cipher

• An asymmetric block cipher

• A stream cipher

What is the solution for the previous problem called?

• Chaining

• Padding

• Mixing

• Shifting