IA 2 - UNIT 4

Question 1

It is a science that consists of
two complementary fields:
cryptography and cryptanalysis

Answer 1

Cryptology

Question 2

encompasses the design
of algorithms that are used to achieve
specific security goals.

Answer 2

cryptography

Question 3

studies techniques with the aim of violating the security goals of these cryptographic algorithms

Answer 3

cryptanalysis

Question 4

The security goals considered in modern cryptography vary according to its application and include

Answer 4

1. confidentiality
2. integrity
3. authentication
4. anonymity
5. non-repudiation

Question 5

The basic primitives in a security system that are used to provide such security goals

Answer 5

cryptographic
primitive

Question 6

• one of the easiest and simplest cryptographic techniques.
• It is a simple substitution cipher where each letter in the plaintext is shifted a fixed number of places down or up the alphabet.

Answer 6

Caesar Cipher

Question 7

a form of substitution cipher where the alphabet is reversed. This means that “A” is swapped with “Z”, “B” with “Y”, and so on.

Answer 7

Atbash Cipher

Question 8

• a polyalphabetic substitution cipher that uses a keyword to shift letters.
• The keyword repeats across the text, creating a unique shift for each letter based on the keyword letter.

Answer 8

Vigenère Cipher

Question 9

• uses a pair of keys—one public and one private.
• The public key encrypts the message, and only the private key can decrypt it. RSA (Rivest-Shamir-Adleman) is a well-known example of a public-key cryptosystem.

Answer 9

Public-key cryptography

Question 10

is a symmetric primitive with the purpose of protecting the secrecy of messages sent over an insecure channel.

Answer 10

block cipher

Question 11

• highest level of security
• was introduced by Shannon and is achieved when the ciphertext does not reveal any information about the plaintext, or in other words, if the plaintext and the ciphertext are statistically independent.

Answer 11

perfect security

Question 12

• A common model assumed in conventional cryptography
• model where the end-users of the communication channel are assumed trusted.

Answer 12

black-box
model

Question 13

• The attacker can observe ciphertexts without any access to plaintexts.
• This is the weakest attack scenario and if a block cipher is vulnerable to such an attack, it is considered completely useless.

Answer 13

ciphertext-only

Question 14

The attacker observes a number of plaintexts and their corresponding ciphertexts

Answer 14

known-plaintext

Question 15

The attacker can choose plaintexts (ciphertexts) to be encrypted (decrypted) before the attack and observes their corresponding ciphertexts (plaintexts) during the attack.

Answer 15

chosen-plaintext

Question 16

On top of the chosen-plaintext (ciphertext) capabilities mentioned above, the attacker can choose plaintexts (ciphertexts) during the attack based on some intermediate results obtained during the attack.

Answer 16

Adaptively chosen-plaintext

Question 17

The attacker can encrypt (decrypt) plaintexts (ciphertexts) with the attacked key and other keys related to it, where such relation is known or even chosen by the attacker.

Answer 17

Related-key

Question 18

a technique for analyzing block ciphers by examining how differences in input plaintexts lead to differences in output ciphertexts. It identifies statistical patterns that can be exploited to uncover key information

Answer 18

Differential cryptanalysis

Question 19

a statistical method for analyzing block ciphers by finding linear relationships between plaintext, ciphertext, and key bits. It aims to exploit these relationships to recover key information.

Answer 19

Linear cryptanalysis

Question 20

a hybrid attack method that combines differential and linear cryptanalysis to exploit vulnerabilities in block ciphers.

Answer 20

Differential-linear cryptanalysis

Question 21

extends traditional differential cryptanalysis by analyzing not just first-order differences but also higher-order differences in the input and output of block ciphers to uncover vulnerabilities.

Answer 21

Higher order differential cryptanalysis

Question 22

a method that analyzes specific truncated differences in plaintext and ciphertext, allowing attackers to focus on subsets of bits rather than requiring full matches.

Answer 22

Truncated differential cryptanalysis

Question 23

a technique that analyzes block ciphers by exploiting specific combinations of input bits (integrals) and their predictable output patterns over multiple rounds.

Answer 23

Integral cryptanalysis

Question 24

a method that exploits specific input differences that cannot produce certain output differences in a block cipher, using these impossibilities to aid in key recovery.

Answer 24

Impossible differential cryptanalysis

Question 25

new trends in cryptanalysis of
block ciphers

Answer 25

1. Adapting Machine Learning in Cryptanalysis
2. Quantum Computing Impacts
3. Exploring Side-channel Attacks

Question 26

The integration of machine learning techniques into cryptanalysis has shown promise for automating and improving attack efficacy.

Answer 26

Adapting Machine Learning in Cryptanalysis

Question 27

With the rise of quantum computing, traditional
cryptanalysis techniques are challenged,
necessitating new strategies for block ciphers.

Answer 27

new trends in cryptanalysis of
block ciphers

Question 28

Side-channel attacks exploit physical
implementations of cryptographic algorithms, providing new avenues for breaking block ciphers.

Answer 28

Exploring Side-channel Attacks

Question 29

attacks on block ciphers

Answer 29

1. Differential cryptanalysis
2. linear cryptanalysis
3. Differential-linear cryptanalysis
4. Higher order differential cryptanalysis
5. Truncated Differential Cryptanalysis
6. Integral Cryptanalysis
7. Impossible Differential Cryptanalysis