NNAT3 Pattern Recognition

Question 1

What is a Caesar cipher?

Accepted Answer

A substitution cipher that shifts each letter by a fixed number of positions

Answer

A modern encryption algorithm

Answer

A random letter replacement

Answer

A mathematical hash

Question 2

What is frequency analysis used for in cryptography?

Accepted Answer

To break substitution ciphers by analyzing letter frequency patterns

Answer

To count words in a document

Answer

To measure radio frequencies

Answer

To analyze sound waves

Question 3

What is the difference between a cipher and a code?

Accepted Answer

A cipher transforms individual characters; a code replaces entire words or phrases

Answer

They are the same thing

Answer

A code is more secure

Answer

A cipher is older

Question 4

What is a transposition cipher?

Accepted Answer

A cipher that rearranges the order of letters without changing them

Answer

A cipher that replaces letters with other letters

Answer

A modern computer encryption

Answer

A hash function

Question 5

What is a one-time pad?

Accepted Answer

A theoretically unbreakable cipher using a random key as long as the message

Answer

A single-use notebook

Answer

A disposable computer

Answer

A temporary password

Question 6

What is the Enigma machine?

Accepted Answer

A WWII German cipher machine using rotors for polyalphabetic encryption

Answer

A modern computer

Answer

A code-breaking device

Answer

A telegraph machine