NNAT3 Pattern Recognition 1

Question 1

What is a Caesar cipher?

Accepted Answer

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

Answer

The Caesar cipher shifts each letter in the plaintext by a fixed number of positions in the alphabet. For example, with a shift of 3, A becomes D.

Question 2

What is frequency analysis used for in cryptography?

Accepted Answer

To break substitution ciphers by analyzing letter frequency patterns

Answer

Frequency analysis exploits the fact that certain letters (like E, T, A in English) appear more often, allowing codebreakers to identify substitution patterns.

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

Ciphers operate on individual characters (letter by letter substitution or transposition), while codes replace entire words or phrases with other words or symbols.

Question 4

What is a transposition cipher?

Accepted Answer

A cipher that rearranges the order of letters without changing them

Answer

Transposition ciphers keep the original letters but rearrange their positions. Examples include rail fence and columnar transposition ciphers.

Question 5

What is a one-time pad?

Accepted Answer

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

Answer

The one-time pad uses a truly random key at least as long as the message, XORed with the plaintext. When used correctly, it is mathematically proven to be unbreakable.

(NNAT3) Naglieri Nonverbal Ability Test 3 Practice Test

(NNAT3) Naglieri Nonverbal Ability Test 3 Practice Test

NNAT3 Pattern Recognition 1