Computer Hardware and Networking MCQ Quiz Hub

1. The main motive for using steganography is that hackers or other users can hide a secret message behind a ______________.
Program file
Special file
Ordinary file
Encrypted file

2. People will normally think it as a normal/regular file and your secret message will pass on without any _____________
Cracking
Decryption
Suspicion
Encryption

3. By using ______________ you can diminish the chance of data leakage.
Steganography
Chorography
Tomography
Cryptography

4. Which mode of operation has the worst “error propagation” among the following?
EC
B CB
CBC
OFB

5. Which block mode limits the maximum throughput of the algorithm to the reciprocal of the time for one execution?
EC
B CB
CTR
OFB

6. Which mode requires the implementation of only the encryption algorithm?
OF
B CTR
CBC
ECB

7. Which of the following modes of operation does not involve feedback?
OF
B CTR
CBC
ECB

8. Which of the following is a natural candidates for stream ciphers?
OF
B ECB
CBC
CFB

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

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

11. How many rounds does the AES-192 perform?
16
12
14
10

12. What is the expanded key size of AES-192?
60 words
32 words
52 words
44 words

13. The 4×4 byte matrices in the AES algorithm are called_____
Permutations
Transitions
Words
States

14. In AES the 4×4 bytes matrix key is transformed into a keys of size __________.
60 words
32 words
52 words
44 words

15. For the AES-128 algorithm there are __________ similar rounds and _________ roundis different.
9 ; the last
8 ; the first and last
10 ; no
2 pair of 5 similar rounds ; every alternate

16. There is an addition of round key before the start of the AES round algorithms.
True
False
none
All of the mentioned

17. How many computation rounds does the simplified AES consists of?
10
8
2
5

18. On comparing AES with DES, which of the following functions from DES does not have an equivalent AES function?
Permutation P
Swapping of halves
XOR of subkey with function f
F function

19. What is the block size in the Simplified AES algorithm?
36 bits
16 bits
40 bits
8 bits

20. . What is the block size in the Simplified AES algorithm?
36 bits
16 bits
40 bits
8 bits

21. What is the key size in the S-AES algorithm?
32 bits
24 bits
16 bits
None of the mentioned

22. Which of the following is a faulty S-AES step function?
Mix Columns
Add round key
Byte substitution
Shift rows

23. How many step function do Round 1 and 2 each have in S-AES?
1 and 4
3 and 4
Both 4
4 and 3

24. The inverse transformation matrix times the forward transformation matrix equals the identity matrix.
True
False
none
all

25. How many round keys are generated in the AES algorithm?
12
11
10
8

26. DES follows_________.
SP Networks
Feistel Cipher Structure
Caesars Cipher
Hash Algorithm

27. The DES Algorithm Cipher System consists of ____________rounds (iterations) each with a round key.
16
9
12
18

28. The DES algorithm has a key length of ______.
16 Bits
32 Bits
64 Bits
128 Bits

29. In the DES algorithm the round key is __________ bit and the Round Input is ____________bits.
48, 32
32, 32
56, 24
64,32

30. In the DES algorithm the Round Input is 32 bits, which is expanded to 48 bits via____________.
Addition of ones
Addition of zeros
Duplication of the existing bits
Scaling of the existing bits

31. The Initial Permutation table/matrix is of size _____.
4×8
8×8
12×8
16×8

32. The number of unique substitution boxes in DES after the 48 bit XOR operationare___.
4
8
12
16

33. What is the number of possible 3 x 3 affine cipher transformations?
840
168
1344
1024

34. The S-Box is used to provide confusion, as it is dependent on the unknown key.
True
False
none
all

35. For p = 11 and q = 17 and choose e=7. Apply RSA algorithm where PT message=88and thus find the CT.
64
11
64
23

36. For p = 11 and q = 17 and choose e=7. Apply RSA algorithm where Ciphermessage=11 and thus find the plain text.
122
143
111
88

37. In an RSA system the public key of a given user is e = 31, n = 3599. What is the privatekey of this user?
1023
2432
2412
3031

38. Compute private key (d, p, q) given public key (e=23, n=233 ´ 241=56,153).
32432
19367
12543
35212

39. RSA is also a stream cipher like Merkel-Hellman.
True
False
none
all

40. In the RSA algorithm, we select 2 random large values ‘p’ and ‘q’. Which of the following is the property of ‘p’ and ‘q’?
p/q should give no remainder
p and q should be prime
p and q should be co-prime
p and q should be divisible by Ф(n)

41. In RSA, Ф(n) = _______ in terms of p and q.
(p+1)(q+1)
(p-1)(q-1)
(p)(q)
(p)/(q)

42. For p = 11 and q = 19 and choose e=17. Apply RSA algorithm where message=5 andfind the cipher text.
C=23
C=56
C=92
C=80

43. For p = 11 and q = 19 and choose d=17. Apply RSA algorithm where Cipher message=80 and thus find the plain text.
5
12
43
54

44. Perform encryption on the following PT using RSA and find the CT. p = 3; q = 11; M= 5.
18
12
26
28

45. Perform encryption on the following PT using RSA and find the CT. p = 5; q = 11; M= 9.
43
14
112
54

46. Perform encryption on the following PT using RSA and find the CT. p = 7; q = 11; M= 8.
58
34
123
57

47. Perform encryption on the following PT using RSA and find the CT. p = 11; q = 13;M = 7.
78
45
124
25

48. n = 35; e = 5; C = 10. What is the plaintext (use RSA)?
2
4
5
6