1. A CSPRBG is defined as one that passes the __ test.
a) Runs test
b) Maurer’s Universal statistical test
c) Frequency Test
d) On-bit test
Explanation: A CSPRBG is defined as one that passes the one-bit test.
2. Find the first 8 bits for Blum Blum Shub Bit Generator when seed = 101355 and n = 192649.
a) 10101010
b) 11100010
c) 11001011
d) 11001110
Explanation: The blum blum shub algorithm is as follows-
Xo = s2 mod n
for i=1 to 8
Xi = X(i-1)2 mod n
Bi = Xi mod 2
Using this we compute the bits as – 11001110.
3. Which of these modes is an appropriate mode for PRNG?
a) ECB
b) CBC
c) CFB
d) CTR
Explanation: CTR and OFB are suitable modes for PRNG.
4. Which mode is recommend for the X9.82 Random number generator?
a) OFB
b) CBC
c) CFB
d) CTR
Explanation: OFB is the recommended mode for the X9.82 Random number generator.
5. AES PRNG produces bits outputs of size
a) 512 bits
b) 128 bits
c) 256 bits
d) 64 bits
Explanation: AES PRNG produces bits outputs of size 128 bits.
6. Which mode is recommend for the ANSI standard X9.82 Random number generator?
a) OFB
b) CTR
c) CFB
d) CFB
Explanation: CTR is the recommended mode for the ANSI standard X9.82 Random number generator.
7. The CTR algorithm for PRNG is known as
a) CTR_PRNG
b) X-SESS
c) CTR-SESS
d) CTR_DRBG
Explanation: The CTR algorithm for PRNG is known as CTR_DRBG.
8. Which mode is recommend for the RFC 4086 Random number generator?
a) CFB
b) CBC
c) OFB
d) CTR
Explanation: OFB is the recommended mode for the RFC 4086 Random number generation.
9. Which mode is less prone to decryption : PRNG using CTR / PRNG using OFB?
a) OFB
b) CTR
c) Both are equally prone
d) Both can’t be decrypted
Explanation: CTR mode is more prone than the OBF mode.
10. ANSI X9.17 uses a seed of size
a) 56 bits
b) 64 bits
c) 32 bits
d) 128 bits
Explanation: The seed in ANSI X9.17 is of 64 bits and the randomly generated keys are of size 56 bits.