laboursonline – MCQs, Mock Tests | Computer Hardware and Networking Information and Network Security Set 2

The main motive for using steganography is that hackers or other users can hide a secret message behind a ______________.

1. Program file
2. Special file
3. Ordinary file
4. Encrypted file

✅ Correct Answer: 3

People will normally think it as a normal/regular file and your secret message will pass on without any _____________

1. Cracking
2. Decryption
3. Suspicion
4. Encryption

✅ Correct Answer: 3

By using ______________ you can diminish the chance of data leakage.

1. Steganography
2. Chorography
3. Tomography
4. Cryptography

✅ Correct Answer: 1

Which mode of operation has the worst “error propagation” among the following?

1. EC
2. B CB
3. CBC
4. OFB

✅ Correct Answer: 1

Which block mode limits the maximum throughput of the algorithm to the reciprocal of the time for one execution?

1. EC
2. B CB
3. CTR
4. OFB

✅ Correct Answer: 3

Which mode requires the implementation of only the encryption algorithm?

1. OF
2. B CTR
3. CBC
4. ECB

✅ Correct Answer: 2

Which of the following modes of operation does not involve feedback?

1. OF
2. B CTR
3. CBC
4. ECB

✅ Correct Answer: 1

Which of the following is a natural candidates for stream ciphers?

1. OF
2. B ECB
3. CBC
4. CFB

✅ Correct Answer: 1

Which one of the following is not a cryptographic algorithm- JUPITER, Blowfish, RC6, Rijndael and Serpent?

1. Rijndael
2. Serpent
3. Blowfish
4. JUPITER

✅ Correct Answer: 4

Which algorithm among- MARS, Blowfish, RC6, Rijndael and Serpent -was chosen asthe AES algorithm?

1. Rijndael
2. RC6
3. Blowfish
4. MARS

✅ Correct Answer: 4

How many rounds does the AES-192 perform?

1. 16
2. 12
3. 14
4. 10

✅ Correct Answer: 2

What is the expanded key size of AES-192?

1. 60 words
2. 32 words
3. 52 words
4. 44 words

✅ Correct Answer: 3

The 4×4 byte matrices in the AES algorithm are called_____

1. Permutations
2. Transitions
3. Words
4. States

✅ Correct Answer: 4

In AES the 4×4 bytes matrix key is transformed into a keys of size __________.

1. 60 words
2. 32 words
3. 52 words
4. 44 words

✅ Correct Answer: 4

For the AES-128 algorithm there are __________ similar rounds and _________ roundis different.

1. 9 ; the last
2. 8 ; the first and last
3. 10 ; no
4. 2 pair of 5 similar rounds ; every alternate

✅ Correct Answer: 1

There is an addition of round key before the start of the AES round algorithms.

1. True
2. False
3. none
4. All of the mentioned

✅ Correct Answer: 1

How many computation rounds does the simplified AES consists of?

1. 10
2. 8
3. 2
4. 5

✅ Correct Answer: 2

On comparing AES with DES, which of the following functions from DES does not have an equivalent AES function?

1. Permutation P
2. Swapping of halves
3. XOR of subkey with function f
4. F function

✅ Correct Answer: 2

What is the block size in the Simplified AES algorithm?

1. 36 bits
2. 16 bits
3. 40 bits
4. 8 bits

✅ Correct Answer: 3

. What is the block size in the Simplified AES algorithm?

1. 36 bits
2. 16 bits
3. 40 bits
4. 8 bits

✅ Correct Answer: 3

What is the key size in the S-AES algorithm?

1. 32 bits
2. 24 bits
3. 16 bits
4. None of the mentioned

✅ Correct Answer: 3

Which of the following is a faulty S-AES step function?

1. Mix Columns
2. Add round key
3. Byte substitution
4. Shift rows

✅ Correct Answer: 3

How many step function do Round 1 and 2 each have in S-AES?

1. 1 and 4
2. 3 and 4
3. Both 4
4. 4 and 3

✅ Correct Answer: 4

The inverse transformation matrix times the forward transformation matrix equals the identity matrix.

1. True
2. False
3. none
4. all

✅ Correct Answer: 1

How many round keys are generated in the AES algorithm?

1. 12
2. 11
3. 10
4. 8

✅ Correct Answer: 2

DES follows_________.

1. SP Networks
2. Feistel Cipher Structure
3. Caesars Cipher
4. Hash Algorithm

✅ Correct Answer: 2

The DES Algorithm Cipher System consists of ____________rounds (iterations) each with a round key.

1. 16
2. 9
3. 12
4. 18

✅ Correct Answer: 1

The DES algorithm has a key length of ______.

1. 16 Bits
2. 32 Bits
3. 64 Bits
4. 128 Bits

✅ Correct Answer: 3

In the DES algorithm the round key is __________ bit and the Round Input is ____________bits.

1. 48, 32
2. 32, 32
3. 56, 24
4. 64,32

✅ Correct Answer: 1

In the DES algorithm the Round Input is 32 bits, which is expanded to 48 bits via____________.

1. Addition of ones
2. Addition of zeros
3. Duplication of the existing bits
4. Scaling of the existing bits

✅ Correct Answer: 4

The Initial Permutation table/matrix is of size _____.

1. 4×8
2. 8×8
3. 12×8
4. 16×8

✅ Correct Answer: 2

The number of unique substitution boxes in DES after the 48 bit XOR operationare___.

1. 4
2. 8
3. 12
4. 16

✅ Correct Answer: 2

What is the number of possible 3 x 3 affine cipher transformations?

1. 840
2. 168
3. 1344
4. 1024

✅ Correct Answer: 3

The S-Box is used to provide confusion, as it is dependent on the unknown key.

1. True
2. False
3. none
4. all

✅ Correct Answer: 1

For p = 11 and q = 17 and choose e=7. Apply RSA algorithm where PT message=88and thus find the CT.

1. 64
2. 11
3. 64
4. 23

✅ Correct Answer: 2

For p = 11 and q = 17 and choose e=7. Apply RSA algorithm where Ciphermessage=11 and thus find the plain text.

1. 122
2. 143
3. 111
4. 88

✅ Correct Answer: 4

In an RSA system the public key of a given user is e = 31, n = 3599. What is the privatekey of this user?

1. 1023
2. 2432
3. 2412
4. 3031

✅ Correct Answer: 4

Compute private key (d, p, q) given public key (e=23, n=233 ´ 241=56,153).

1. 32432
2. 19367
3. 12543
4. 35212

✅ Correct Answer: 2

RSA is also a stream cipher like Merkel-Hellman.

1. True
2. False
3. none
4. all

✅ Correct Answer: 1

In the RSA algorithm, we select 2 random large values ‘p’ and ‘q’. Which of the following is the property of ‘p’ and ‘q’?

1. p/q should give no remainder
2. p and q should be prime
3. p and q should be co-prime
4. p and q should be divisible by Ф(n)

✅ Correct Answer: 2

In RSA, Ф(n) = _______ in terms of p and q.

1. (p+1)(q+1)
2. (p-1)(q-1)
3. (p)(q)
4. (p)/(q)

✅ Correct Answer: 2

For p = 11 and q = 19 and choose e=17. Apply RSA algorithm where message=5 andfind the cipher text.

1. C=23
2. C=56
3. C=92
4. C=80

✅ Correct Answer: 4

For p = 11 and q = 19 and choose d=17. Apply RSA algorithm where Cipher message=80 and thus find the plain text.

1. 5
2. 12
3. 43
4. 54

✅ Correct Answer: 1

Perform encryption on the following PT using RSA and find the CT. p = 3; q = 11; M= 5.

1. 18
2. 12
3. 26
4. 28

✅ Correct Answer: 3

Perform encryption on the following PT using RSA and find the CT. p = 5; q = 11; M= 9.

1. 43
2. 14
3. 112
4. 54

✅ Correct Answer: 2

Perform encryption on the following PT using RSA and find the CT. p = 7; q = 11; M= 8.

1. 58
2. 34
3. 123
4. 57

✅ Correct Answer: 4

Perform encryption on the following PT using RSA and find the CT. p = 11; q = 13;M = 7.

1. 78
2. 45
3. 124
4. 25

✅ Correct Answer: 3

n = 35; e = 5; C = 10. What is the plaintext (use RSA)?

1. 2
2. 4
3. 5
4. 6

✅ Correct Answer: 3