Chp 1

Question 1

What is encryption?

Answer 1

Changing plaintext to ciphertext.

Question 2

What is decryption?

Answer 2

The process of changing ciphertext to plaintext.

Question 3

Mono-alphabetic

Answer 3

single mapping from our alphabet to a cipher alphabet.

Question 4

Polyalphabetic

Answer 4

Mapping our alphabet to several cipher alphabets.

Question 5

One-time Pad

Answer 5

Considered ubreakable because it only uses cipher code once.

Question 6

Psuedo-Random Number Generators (PRNG)

Answer 6

Repeats the random numbers after a given time (periodic). Fast and deterministic.

Question 7

True Random Number Generators

Answer 7

Generates a true random number and uses some form of a random process. Non-deterministic and aperiodic.

Question 8

Frequency Analysis

Answer 8

Cipher cracking method that IDs patterns and variations in the probability of codes.

Question 9

Entropy

Answer 9

Measures the level of unpredictability.

Question 10

ASCII

Answer 10

Encoding method that has 8-bit values and up to 256 characters.

Question 11

UTF-16

Answer 11

Encoding method that has 16-bit values and up to 65,536 characters.

Question 12

Is hardware or software encryption more efficient?

Answer 12

Hardware encryption.

Question 13

Hardware Security Module (HSM)

Answer 13

Tamper-evident and intrusion-resistant physical device that safeguards and manages cryptographic keys and provides cryptographic processing.

Question 14

Trusted Platform Module (TPM)

Answer 14

A dedicated processor that handles hardware-level encryption and contains encryption keys. Enables FDE.

Question 15

Binary Math

Answer 15

Knowing what combination of binary digits will produce a binary “1”.

Question 16

Binary ‘AND’

Answer 16

The first and second numbers you are ‘ANDing’ must be 1 for the answer to be 1. Anything else = 0.

Question 17

Binary ‘OR’

Answer 17

If either or both numbers are “1”, the answer is “1”.

Question 18

Binary ‘XOR’ (exclusive or)

Answer 18

One, but not both, numbers are “1” then the answer is “1”. Anything else is a “0”.

Question 19

Modulus Operator Math

Answer 19

Divide the first number by the second and return the remainder. Example: 5 mod 2 = 1

Question 20

Combination vs Permutation

Answer 20

combinations = not concerned with the order / permutations = all options considered, including sequence.

Question 21

Probability

Answer 21

The likelihood of an event happening.

Question 22

Prime Number

Answer 22

Can only be divided by 1 and itself.

Question 23

Pigpen Cipher

Answer 23

mono-alphabetic substitution cipher that maps plaintext to graphical characters.

Question 24

Rail Code

Answer 24

Scrambles text by writing it in a sequence across several rails.

Question 25

BIFID

Answer 25

Uses a grid to map the letters into numeric values.

Question 26

Playfair

Answer 26

5 x 5 matrix that contains the alphabet less the letter 'J'. Has a set of rules using columns and rows.

Question 27

Morse Code

Answer 27

Encoding method that translates characters into sequences of dots.

Question 28

Vigenere

Answer 28

Polyalphabetic cipher that uses a mapping based on a keyword.

Question 29

Caesar

Answer 29

Mono-alphabetic substitution cipher known as a shift cipher. Plaintext is replaced by a letter that is further down.

Question 30

One-Time Pad

Answer 30

Cipher code mapping that is used only once.

Question 31

Four-square Cipher

Answer 31

Uses four 5 x 5 matrices arranged in a square. Each matrix has 25 letters.

Question 32

Enigma Machine

Answer 32

Uses a polyalphabetic substitution cipher and a secret key.