1. What is the maximum size of the key in blowfish algorithm?.
A. 256 bits.
B. 512 bits.
C. 56 bytes.
D. 48 bytes.
Answer= 56 bytes
2. Blowfish encrypts blocks of plaintext which have size.
A. 256 bits.
B. 64 bits.
C. 72 bits.
D. 128 bits.
Answer= 72 bits
3. The blowfish algorithm can be implemented on 16 bit processors..
A. TRUE.
B. FALSE.
C. Nothing can be said.
D. None of the mentioned.
Answer= FALSE
4. What is the minimum size of the key in blowfish algorithm?.
A. 64 bits.
B. 32 bits.
C. 56 bits.
D. 48 bits.
Answer= 32 bits
5. The blowfish algorithm's key expansion converts a key of at most 448 bits into several subkey arrays totaling ___________ bytes..
A. 4096.
B. 4608.
C. 4168.
D. 4864.
Answer= 4168
6. Blowfish algorithm uses the Feistel Structure..
A. TRUE.
B. FALSE.
C. Nothing can be said.
D. None of the mentioned.
Answer= TRUE
7. XOR and addition operations take place on bytes of size.
A. 8 bits.
B. 16 bits.
C. 32 bits.
D. 64 bits.
Answer= 32 bits
8. How many S-boxes are present in the blowfish algorithm?.
A. 2.
B. 4.
C. 6.
D. 8.
Answer= 4
9. How many entries are present in each of the S-boxes present in the blowfish algorithm?.
A. 256.
B. 512.
C. 1024.
D. 64.
Answer= 256
10. In blowfish, the keys are stored in the form of an array ranging from K1, K2 to Ki. What is the value of i?.
A. 12.
B. 16.
C. 8.
D. 14.
Answer= 14
11. To generate the sub-key P1 to P18 we use the hexadecimal equivalent digits of ____________.
A. 0.7864.
B. 0.1415.
C. 0.1542.
D. 0.7535.
Answer= 0.1415
12. P17 gets XORed with.
A. K3.
B. K12.
C. K17.
D. K6.
Answer= K3
13. P15 gets XORed with.
A. K3.
B. K14.
C. K1.
D. K6.
Answer= K1
14. What is the number of iterations required in total to generate all the sub-keys in blowfish?.
A. 512.
B. 521.
C. 256.
D. 128.
Answer= 521
15. A single blowfish s-box converts 8-bits to _________ bits..
A. 32.
B. 44.
C. 56.
D. 64.
Answer= 32
16. The 32bit output of s-box 1 is XORed with s-box 2..
A. TRUE.
B. FALSE.
C. Nothing can be said.
D. None of the mentioned.
Answer= TRUE
17. Which of the following statements are true with respect to the blowfish algorithm – i) Provided key is large enough, brute-force key search is not practical, especially given the high key schedule cost ii) Key dependent S-boxes and sub keys make analysis very difficult iii) Changing both halves in each round increases security iv) Blowfish has improved avalanche effects.
A. i) ii) and iv).
B. ii) and iii).
C. i).
D. All are true.
Answer= All are true