Cryptography: The Art of Code Security

Question 1

Which of the following is an undesirable characteristic of a cryptographic hash function?

Accepted Answer

Easily invertible

Answer

Deterministic

Answer

Collision-resistant

Answer

One-way

Question 2

Identify the block cipher algorithm from the following options:

Accepted Answer

DES

Accepted Answer

AES

Answer

RSA

Answer

MD5

Question 3

Which of the following is an asymmetric encryption algorithm?

Accepted Answer

RSA

Answer

DES

Answer

AES

Answer

Twofish

Question 4

Which of the following is a well-known symmetric encryption algorithm?

Accepted Answer

AES

Answer

RSA

Answer

SHA-256

Answer

Diffie-Hellman

Question 5

In symmetric encryption, the same key is used for both encryption and decryption. Which of the following is a symmetric encryption algorithm?

Accepted Answer

AES

Answer

RSA

Answer

SHA-256

Answer

ElGamal

Question 6

In a symmetric encryption algorithm, the same key is used for both encryption and decryption. Which of the following is an example of a symmetric encryption algorithm?

Accepted Answer

AES

Answer

RSA

Answer

SHA-256

Answer

ElGamal

Question 7

Which of the following is a symmetric encryption algorithm?

Accepted Answer

DES

Answer

RSA

Answer

SHA-256

Answer

ECC

Question 8

Which of the following is NOT a type of cryptographic algorithm?

Accepted Answer

Digital certificate

Answer

Symmetric-key encryption

Answer

Public-key encryption

Answer

Hash function

Question 9

Which of these is a symmetric encryption algorithm?

Accepted Answer

AES

Answer

RSA

Answer

SHA-256

Answer

ECC

Question 10

Which of the following is an asymmetric encryption algorithm, where different keys are used for encryption and decryption?

Accepted Answer

RSA

Answer

AES

Answer

DES

Answer

Twofish

Question 11

Which of the following is NOT a type of cryptographic algorithm?

Accepted Answer

File compression algorithm

Answer

Symmetric-key algorithm

Answer

Asymmetric-key algorithm

Answer

Hash function

Question 12

Which of the following is not a cryptographic algorithm?

Accepted Answer

Compression

Answer

AES

Answer

RSA

Answer

SHA-256

Question 13

Which of the following is not a type of cryptographic algorithm?

Accepted Answer

Insertion sort algorithm

Answer

Symmetric-key algorithm

Answer

Asymmetric-key algorithm

Answer

Hash function

Question 14

In cryptography, which algorithm type uses the same key for both encrypting and decrypting data?

Accepted Answer

AES

Answer

RSA

Answer

SHA-256

Answer

ECC

Question 15

Which of the following is a stream cipher?

Accepted Answer

RC4

Answer

AES

Answer

DES

Answer

RSA

Question 16

Which of the following is NOT a type of cryptographic algorithm?

Accepted Answer

Watermarking

Answer

Symmetric Encryption

Answer

Asymmetric Encryption

Answer

Hashing

Question 17

Which characteristic is essential for a robust cryptographic algorithm?

Accepted Answer

Ciphertext indistinguishable from random data

Answer

Vulnerability to brute-force attacks

Answer

Easily breakable nature

Answer

Simplicity of implementation

Question 18

Within the realm of cryptography, which algorithm falls under the classification of a stream cipher?

Accepted Answer

RC4

Answer

AES

Answer

RSA

Answer

SHA-256

Question 19

Which of the following is NOT a fundamental cryptographic algorithm category?

Accepted Answer

Compression

Answer

Symmetric Encryption

Answer

Asymmetric Encryption

Answer

Stream Cipher

Question 20

In cryptography, what is the main purpose of a hash function?

Accepted Answer

Creating unique digital fingerprints of data to verify its integrity

Answer

Encrypting data for secure transmission

Answer

Generating random numbers for cryptographic purposes

Answer

Compressing data to reduce its size

Question 21

Which property of a secure hash function makes it computationally impractical to find two distinct inputs that generate the same hash value?

Accepted Answer

Collision resistance

Answer

Preimage resistance

Answer

Second preimage resistance

Answer

Reversibility

Question 22

Which of the following is not a type of cryptographic algorithm?

Accepted Answer

Compression algorithm

Answer

Symmetric-key algorithm

Answer

Asymmetric-key algorithm

Answer

Hash function

Question 23

Identify the essential properties of a cryptographic hash function.

Accepted Answer

Preimage resistance

Accepted Answer

Second preimage resistance

Accepted Answer

Collision resistance

Question 24

Identify the symmetric encryption algorithm from the options below:

Accepted Answer

AES

Answer

RSA

Answer

SHA-256

Answer

ECC

Question 25

Which property of cryptographic hash functions guarantees that different inputs will always produce unique hash values?

Accepted Answer

Collision Resistance

Answer

Ease of Computation

Answer

Reversibility

Question 26

Which element is NOT a direct component of a Public Key Infrastructure (PKI)?

Accepted Answer

Encryption Algorithm

Answer

Certificate Authority (CA)

Answer

Registration Authority (RA)

Answer

Root Certificate

Question 27

In public-key cryptography, which algorithm is used to encrypt messages sent to the receiver?

Accepted Answer

RSA

Answer

AES

Answer

SHA-256

Question 28

Identify the key characteristic that distinguishes symmetric encryption algorithms from asymmetric encryption algorithms.

Accepted Answer

Use of a single key vs. different keys for encryption and decryption

Answer

Computational speed: Symmetric algorithms are faster

Answer

Security strength: Asymmetric algorithms are more secure

Answer

Encryption target: Symmetric algorithms can only encrypt data

Question 29

In public-key cryptography, what is the primary function of a digital certificate?

Accepted Answer

Verifies the identity of the public key owner, ensuring their legitimacy.

Answer

Encrypts the public key for secure storage.

Answer

Generates a new public key for the certificate owner.

Answer

Stores the private key of the certificate owner for safekeeping.

Question 30

What is the key characteristic of a collision-resistant hash function?

Accepted Answer

It is extremely difficult to find two messages with the same hash value.

Answer

It is simple to find a message with a specific hash value.

Answer

It is easy to find a second message with the same hash value as a given message.

Question 31

Which of the following is NOT a cryptographic hash function?

Accepted Answer

AES

Answer

MD5

Answer

SHA-256

Question 32

Which of the following is a characteristic of a strong cryptographic algorithm?

Accepted Answer

Resistant to brute-force attacks

Answer

Easy to break

Answer

Fast execution speed

Answer

Compatible with all software

Question 33

In cryptography, what process converts plaintext into an encrypted format called ciphertext?

Accepted Answer

Encryption

Answer

Decryption

Answer

Hashing

Answer

Authentication

Question 34

Which block cipher mode of operation employs an initialization vector (IV) to thwart replay attacks?

Accepted Answer

Cipher Block Chaining (CBC)

Answer

Counter Mode (CTR)

Answer

Electronic Codebook (ECB)

Answer

Output Feedback (OFB)

Question 35

What is the concept of zero-knowledge proofs, and how do they allow one party to prove they know a secret without revealing it?

Accepted Answer

Zero-knowledge proofs are techniques where one party (the prover) convinces another (the verifier) that they know a secret without sharing it.

Answer

Zero-knowledge proofs are equations that guarantee the secrecy of a shared secret between two parties.

Answer

Zero-knowledge proofs require the verifier to know the secret in advance to verify the proof.

Question 36

In public-key cryptography, how are the public and private keys used?

Accepted Answer

Public key encrypts, private key decrypts

Answer

Private key encrypts, public key decrypts

Answer

Both keys encrypt and decrypt

Answer

Both keys decrypt

Question 37

Which type of encryption algorithm encrypts plaintext in continuous streams of bits?

Accepted Answer

Stream cipher

Answer

Block cipher

Answer

Hash function

Answer

MAC

Question 38

What is the primary purpose of a hash function in cryptography?

Accepted Answer

To create a unique and irreversible digest of data

Answer

To encrypt plaintext

Answer

To generate a digital signature

Answer

To establish a shared secret key

Question 39

Which of the following is a commonly used symmetric key encryption algorithm?

Accepted Answer

AES

Answer

RSA

Answer

ECC

Answer

DH

Question 40

What is the primary purpose of a public key infrastructure (PKI)?

Accepted Answer

To manage and verify digital certificates

Answer

To generate encryption keys

Answer

To provide secure communication channels

Answer

To store private keys securely

Question 41

Why is key management crucial in cryptography?

Accepted Answer

Key management ensures the secrecy and trustworthiness of encrypted data.

Answer

Key management is irrelevant in cryptography.

Question 42

Which of the following is NOT a fundamental goal of cryptography?

Accepted Answer

Availability

Answer

Confidentiality

Answer

Integrity

Answer

Authenticity

Question 43

Which type of cipher operates on a block of data at a time, producing a block of ciphertext of the same size?

Accepted Answer

Block cipher

Answer

Stream cipher

Answer

Hash function

Answer

Symmetric-key cipher

Question 44

What is the primary purpose of a hash function?

Accepted Answer

To create a digital fingerprint of data

Answer

To encrypt data

Answer

To generate random numbers

Answer

To store passwords securely

Question 45

What is the primary role of a certificate authority (CA) in public-key infrastructure (PKI)?

Accepted Answer

To issue and manage digital certificates

Answer

To encrypt and decrypt messages

Answer

To store private keys securely

Answer

To verify the identities of users

Question 46

Which of the following is NOT a recommended best practice for maintaining strong cryptography?

Accepted Answer

Reusing the same key for multiple purposes

Answer

Using strong encryption algorithms

Answer

Changing cryptographic keys regularly

Answer

Storing keys securely

Question 47

The process of converting clear, readable data (plaintext) into encrypted data (ciphertext) is known as:

Accepted Answer

Encryption

Answer

Decryption

Answer

Hashing

Answer

Encoding

Question 48

Which of the following is a symmetric-key encryption algorithm, where the same key is used for both encryption and decryption?

Accepted Answer

AES (Advanced Encryption Standard)

Answer

RSA (Rivest-Shamir-Adleman)

Answer

SHA-256 (Secure Hash Algorithm 256)

Answer

ECC (Elliptic Curve Cryptography)

Question 49

What is the purpose of a digital certificate?

Accepted Answer

To verify the identity of a website, organization, or individual

Answer

To encrypt sensitive data for secure transmission

Answer

To generate encryption keys for secure communication

Answer

To certify the integrity of a software update

Question 50

What is the primary role of a hash function in cryptography?

Accepted Answer

To scramble data irreversibly, producing a unique digital fingerprint

Answer

To encrypt plaintext into ciphertext for secure transmission

Answer

To generate random numbers for cryptographic operations

Answer

To verify the authenticity of a digital signature

Question 51

What is the key distinction between a block cipher and a stream cipher?

Accepted Answer

Block ciphers operate on fixed-size blocks of data, while stream ciphers process data one bit or byte at a time

Answer

Stream ciphers are generally faster than block ciphers

Answer

Block ciphers are more vulnerable to cryptanalysis

Answer

Stream ciphers can only be used for encryption, while block ciphers can be used for both encryption and decryption

Question 52

Which of these options is not a cryptographic algorithm?

Accepted Answer

Data Compression

Answer

AES

Answer

RSA

Answer

Hashing

Question 53

What is the primary purpose of a symmetric-key algorithm?

Accepted Answer

Encrypt and decrypt data using the same key

Answer

Encrypt data using one key and decrypt using another

Answer

Generate secure hash values

Answer

Provide digital signatures

Question 54

What is the primary purpose of a digital signature?

Accepted Answer

Verifying the authenticity of a message or digital document

Answer

Encrypting a message for confidentiality

Answer

Generating a hash value for data integrity

Answer

Providing a secure key exchange mechanism

Question 55

Which type of attack exploits differences in the time taken to encrypt different plaintexts?

Accepted Answer

Timing attack

Answer

Brute-force attack

Answer

Replay attack

Answer

Man-in-the-middle attack

Question 56

What is the primary purpose of a cryptographic hash function?

Accepted Answer

To generate a unique and irreversible fingerprint of data

Answer

To encrypt data

Answer

To decrypt data

Answer

To generate a digital signature

Question 57

Which encryption algorithm type utilizes the same key for both encryption and decryption?

Accepted Answer

Symmetric

Answer

Asymmetric

Answer

Block

Answer

Stream

Question 58

What is the fundamental distinction between a block cipher and a stream cipher?

Accepted Answer

Block ciphers encrypt data in fixed-size blocks, while stream ciphers encrypt data as a continuous stream.

Answer

Stream ciphers encrypt data in fixed-size blocks, while block ciphers encrypt data as a continuous stream.

Answer

Block ciphers are generally faster than stream ciphers.

Answer

Stream ciphers offer higher security compared to block ciphers.

Question 59

Which of the following is NOT a commonly used key management technique?

Accepted Answer

Plaintext storage

Answer

Symmetric key encryption

Answer

Asymmetric key encryption

Answer

Digital certificates

Question 60

What is the primary function of a digital signature?

Accepted Answer

To authenticate the origin of a message and ensure its integrity

Answer

To encrypt a message

Answer

To generate a unique and irreversible fingerprint of data

Answer

To provide non-repudiation

Question 61

Define digital signatures and explain their importance in ensuring the authenticity and integrity of digital messages during transmission and reception.

Accepted Answer

Digital signatures are mathematical algorithms that enable the receiver to verify the authenticity, integrity, and origin of a digital message.

Answer

Digital signatures are encrypted messages that allow the receiver to verify the sender's identity.

Answer

Digital signatures are primarily used to reduce the size of large files before sending them over the internet.

Answer

Digital signatures are only used in email communication.

Question 62

Which of the following is NOT a category of symmetric cryptosystems?

Accepted Answer

Hash function

Answer

Block cipher

Answer

Stream cipher

Question 63

Which cryptographic function is widely used to generate a unique digital fingerprint of data?

Accepted Answer

SHA-256

Answer

AES

Answer

RSA

Question 64

What is the primary purpose of a digital signature?

Accepted Answer

To verify the authenticity and integrity of a message

Answer

To ensure message confidentiality

Answer

To encrypt a message securely