Symmetric Encryption (Security+): AES, DES, 3DES Quiz

1. The Substitution-Permutation Network (SPN) structure is used in which of these algorithms?

DES only

AES only

Both AES and DES

Neither AES nor DES

2. DES uses a Feistel network structure with how many rounds to process plaintext?

8 rounds

12 rounds

16 rounds

20 rounds

3. In Galois/Counter Mode (GCM), which cryptographic property is provided in addition to confidentiality?

Key derivation

Authentication

Compression

Randomization

4. The NIST approved DES for federal use until which year, after which it was phased out?

1998

2001

2005

2015

5. AES processes data in blocks and arranges them in a 4x4 matrix of bytes. What is this matrix called?

State

Block

Array

Grid

6. 3DES in EEE (Encrypt-Encrypt-Encrypt) mode uses three different keys. Is this more secure than EDE mode with three keys?

True

False

7. The S-box (substitution box) is a critical component in which step of the AES encryption process?

SubBytes transformation

ShiftRows transformation

MixColumns transformation

AddRoundKey transformation

8. In Counter (CTR) mode, the encryption of a counter value produces what?

A random number

A keystream block

A hash value

A new counter value

9. Which of the following best describes why AES replaced 3DES in modern security standards?

Smaller block size

Faster performance and stronger security

Lower cost of implementation

Simpler key schedule

10. Cipher Feedback (CFB) mode is classified as a stream cipher mode. True or false?

True

False

11. What is the block size used by the Data Encryption Standard (DES)?

64 bits

128 bits

192 bits

256 bits

12. DES was standardized as FIPS 46 in which decade?

1970s

1980s

1990s

2000s

13. What is the effective key length of 3DES when using three independent keys (EDE mode)?

56 bits

112 bits

168 bits

192 bits

14. Which cipher mode requires an initialization vector (IV) to ensure that identical plaintexts produce different ciphertexts?

ECB mode

CBC mode

ECB and CBC modes

None of the above

15. AES was originally known by which name before standardization?

Rijndael

Serpent

Twofish

Blowfish

16. In Electronic Codebook (ECB) mode, identical plaintext blocks produce identical ciphertext blocks. Is this a security concern?

True

False

17. Which key length options are supported by AES?

128, 192, and 256 bits

64, 128, and 256 bits

128 and 256 bits only

192 bits only

18. Triple DES (3DES) applies the DES algorithm how many times in succession?

Two times

Three times

Four times

Six times

19. What is the primary security weakness that led to DES being considered obsolete?

Small block size of 32 bits

Key length of only 56 effective bits

Inefficient round function

Incompatibility with modern hardware

20. How many rounds does the Advanced Encryption Standard (AES) use with a 256-bit key?

10 rounds

12 rounds

14 rounds

16 rounds

Symmetric Crypto Quiz: AES, DES or 3DES?

1. The Substitution-Permutation Network (SPN) structure is used in which of these algorithms?

2.

What first name or nickname would you like us to use?

2. DES uses a Feistel network structure with how many rounds to process plaintext?

3. In Galois/Counter Mode (GCM), which cryptographic property is provided in addition to confidentiality?

4. The NIST approved DES for federal use until which year, after which it was phased out?

5. AES processes data in blocks and arranges them in a 4x4 matrix of bytes. What is this matrix called?

6. 3DES in EEE (Encrypt-Encrypt-Encrypt) mode uses three different keys. Is this more secure than EDE mode with three keys?

7. The S-box (substitution box) is a critical component in which step of the AES encryption process?

8. In Counter (CTR) mode, the encryption of a counter value produces what?

9. Which of the following best describes why AES replaced 3DES in modern security standards?

10. Cipher Feedback (CFB) mode is classified as a stream cipher mode. True or false?

11. What is the block size used by the Data Encryption Standard (DES)?

12. DES was standardized as FIPS 46 in which decade?

13. What is the effective key length of 3DES when using three independent keys (EDE mode)?

14. Which cipher mode requires an initialization vector (IV) to ensure that identical plaintexts produce different ciphertexts?

15. AES was originally known by which name before standardization?

16. In Electronic Codebook (ECB) mode, identical plaintext blocks produce identical ciphertext blocks. Is this a security concern?

17. Which key length options are supported by AES?

18. Triple DES (3DES) applies the DES algorithm how many times in succession?

19. What is the primary security weakness that led to DES being considered obsolete?

20. How many rounds does the Advanced Encryption Standard (AES) use with a 256-bit key?