Question

QUESTION 2 Given random number 10010110, encrypt plain text 11111101 using steam cipher.

Answer 1

In Stream Cipher, plaindigits are combined with random number digits and the combination Operation is XOR. it is a symmetric key cryptography technique in which one bit is encrypted at a time.

random number = 10010110

plain text = 11111101

XOR: In this binary operation the resulting bit evaluates to one, if only exactly one of the bits is set. The truth table for XOR gate is :

X Y OUTPUT

1 1 0

1 0 1

0 1 1

0 0 0

E(K) = Random number XOR plain text = 10010110 XOR 11111101= 01101011

Note: I have taken Stream cipher in this case, since you have mentioned steam cipher in the question, and there is no such steam cipher exists. So, The statement should be stream cipher.