Week 04

Question 1

Plaintext

Plaintext

Answer 1

Readable data or text before it is encrypted into ciphertext.

Question 2

Frequency Analysis

Frequency Analysis

Answer 2

A method of breaking ciphers by studying the frequency of letters or groups of letters in ciphertext.

Question 3

Cryptanalysis

Cryptanalysis

Answer 3

The study and practice of breaking cryptographic codes and understanding weaknesses in encryption methods.

Question 4

Out-of-band

Out-of-band

Answer 4

A communication method where encryption keys or information are shared via a separate channel from the primary data stream.

Question 5

Key

Key

Answer 5

A value used in cryptographic algorithms to encrypt and decrypt data, created using specific algorithms.

Question 6

Substitution/Transposition Cipher

Substitution/Transposition Cipher

Answer 6

Ciphers that replace elements of the plaintext with other symbols (substitution) or rearrange their order (transposition).

Question 7

Algorithm

Algorithm

Answer 7

A set of mathematical rules or instructions for performing encryption, decryption, or data processing.

Question 8

Block Mode Encryption

Block Mode Encryption

Answer 8

An encryption method that processes fixed-size blocks of data at a time rather than one bit or byte at a time.

Question 9

Ciphertext

Ciphertext

Answer 9

Encrypted data that is not readable until it has been decrypted back into plaintext.

Question 10

Key Pair

Key Pair

Answer 10

A pair of keys (public and private) used in asymmetric encryption, where one key encrypts data and the other decrypts it.

Question 11

Message Digest

Message Digest

Answer 11

A fixed-size numerical representation (hash) of a message, used for verifying data integrity.

Question 12

Private Key & Public Key

Private Key & Public Key

Answer 12

In asymmetric encryption, the public key is used for encryption and shared openly, while the private key is kept secret and used for decryption.

Question 12

Non-Repudiation

Non-Repudiation

Answer 12

Assurance that someone cannot deny the authenticity of their signature or message.

Question 12

RNG (Random Number Generator)

RNG (Random Number Generator)

Answer 12

A device or algorithm that generates random numbers, crucial for cryptographic key generation.

Question 13

In-Band

In-Band

Answer 13

A method where encryption keys or information are shared within the same channel as the primary data stream.

Question 14

Key Escrow

Key Escrow

Answer 14

A method where encryption keys are held in a secure third-party location for access if needed.

Question 16

Encoding and Encryption

Encoding and Encryption

Answer 16

Encoding converts data for easy readability or storage, while encryption converts data to secure it against unauthorized access.

Question 16

Key Space

Key Space

Answer 16

The total range of possible values for a cryptographic key.

Question 16

Decoding and Decryption

Decoding and Decryption

Answer 16

Decoding reverses encoding, making data readable again, while decryption reverses encryption to reveal plaintext.

Question 17

Cryptography

Cryptography

Answer 17

The science of securing information through encryption and other techniques.

Question 18

Hashes and Hash Function

Hashes and Hash Function

Answer 18

A hash function generates a fixed-size output (hash) from input data, used for verifying data integrity.

Question 19

Collision

Collision

Answer 19

When two different inputs produce the same hash output, undermining the effectiveness of a hash function.

Question 20

Symmetric/Asymmetric Encryption

Symmetric/Asymmetric Encryption

Answer 20

Symmetric encryption uses one key for both encryption and decryption, while asymmetric encryption uses a pair of keys (public and private).

Question 21

CPTED (Crime Prevention Through Environmental Design)

CPTED (Crime Prevention Through Environmental Design)

Answer 21

A strategy to deter criminal behavior through environmental design and layout.

Question 22

Session Key

Session Key

Answer 22

A temporary key used to encrypt data during a communication session, ensuring secure communication.