Question

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

The question was asked in quiz.

My question comes from Overview in chapter Cryptography Overview, TCP/IP and Communication Networks of Cryptograph & Network Security

Answer 1

Right answer is (d) 11001110

For explanation: The blum blum shub algorithm is as follows

Xo = s^2 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.