Chapter 6 (Domain 2: Asset Security)

Question 1

Caesar cipher

Answer 1

Julius Caesar to communicate with Cicero.
Also known as the ROT3 (or Rotate 3) cipher.
The Caesar cipher is a substitution cipher that is mono-alphabetic

Question 2

Enigma

Answer 2

German military-industrial complex adapted a commercial code machine nicknamed Enigma

Question 3

Ultra

Answer 3

The Allied forces began a top-secret effort known by the code name Ultra to attack the Enigma codes.
The Allies, led by Alan Turing, successfully broke the Enigma code in 1940

Question 4

What are the 4 fundamental goals of cryptographic systems?

Answer 4

• Confidentiality
• Integrity
• Authentication
• Nonrepudiation

Question 5

Two main types of cryptosystems enforce confidentiality

Answer 5

• Symmetric cryptosystems use a shared secret key available to all users of the cryptosystem.
• Asymmetric cryptosystems use individual combinations of public and private keys for each user of the system.

Question 6

How is message integrity enforced?

Answer 6

The use of encrypted message digests, known as digital signatures, created upon transmission of a message.

Question 7

Nonrepudiation

Answer 7

Nonrepudiation provides assurance to the recipient that the message was originated by the sender and not someone masquerading as the sender. It also prevents the sender from claiming that they never sent the message in the first place

Question 8

How is nonrepudiation enforced?

Answer 8

• Nonrepudiation is offered only by public key, or asymmetric, cryptosystems
• Secret key, or symmetric key, cryptosystems (such as simple substitution ciphers) do not provide this guarantee of nonrepudiation.

Question 9

Kerckhoffs’s principle

Answer 9

(Also known as Kerckhoffs’s assumption) is that a cryptographic system should be secure even if everything about the system, except the key, is public knowledge. The principle can be summed up as “The enemy knows the system.”

Question 10

Cryptography

Answer 10

The art of creating and implementing secret codes and ciphers is known as cryptography

Question 11

Cryptanalysis

Answer 11

The study of methods to defeat codes and ciphers

Question 12

Cryptology

Answer 12

Together, cryptography and cryptanalysis are commonly referred to as cryptology

Question 13

Boolean: AND

Answer 13

The AND operation (represented by the ∧ symbol) checks to see whether two values are both true
- Only one combination has 2 values are both true: 1 AND 1 is 1

Question 14

Boolean: OR

Answer 14

The OR operation (represented by the ∨ symbol) checks to see whether at least one of the input values is true
- The only time this is False is when both inputs are false

Question 15

Boolean: NOT

Answer 15

The NOT operation (represented by the ∼ or ! symbol) simply reverses the value of an input variable.
- Gives the opposite value

Question 16

Boolean: XOR

Answer 16

The XOR function returns a true value when only one of the input values is true
- If both values are false or both values are true, the output of the XOR function is false

Question 17

Modulo

Answer 17

The modulo function is the remainder value left over after a division operation is performed.