Encryption

Question 1

Define encryption

Answer 1

Using an algorithm to change data so it can only be read by intended recipient

Question 2

Define decryption

Answer 2

Process of turning encrypted data back to data that can be understood

Question 3

Define cipher

Answer 3

Algorithm used to encrypt or decrypt

Question 4

Plaintext

Answer 4

Unencrypted message

Question 5

Ciphertext

Answer 5

Encrypted message

Question 6

Key

Answer 6

Data that defines how the plaintext will be encrypted

Question 7

Two types of encryption. As well as definition

Answer 7

Symmetric: Uses the same key for both encryption and decryption

Asymmetric: Different keys used for encryption and decryption

Question 8

Define Caesar cipher

Answer 8

A type of substitution cipher. Replaces plaintext with a fixed number of places down the alphabet. Symmetric encryption

Question 9

Disadvantages to a Caesar cipher

Answer 9

Word structure is preserved
Letter frequency is a big clue
Easy to crack with brute force

Question 10

Define Vernam cipher

Answer 10

XOR plaintext with key in binary to produce ciphertext

Question 11

How do you decrypt Vernam cipher

Answer 11

XOR ciphertext with the key