Question 3: Suppose that Alice sends Bob an 8-bit binary message encrypted using an LFSR. Eve intercepts the ciphertext: 00111100 Eve knows that the LFSR uses a recurrence of length 2 (that is, a recurrence of the form In+2 = COXn + Ci Xn+1) and knows that the first 4 bits of plaintext are 1000. (a) Based on this information, what are the first 4 bits of the sequence generated by the LFSR? (Note: they are not just the first 4 bits of ciphertext or of known plaintext!) (b) Use your answer to (a) to deduce the coefficients for the LFSR and decrypt the 8-bit plaintext: CO II c1 = 8-bit plaintext: Question 3: Suppose that Alice sends Bob an 8-bit binary message encrypted using an LFSR. Eve intercepts the ciphertext: 00111100 Eve knows that the LFSR uses a recurrence of length 2 (that is, a recurrence of the form In+2 = COXn + Ci Xn+1) and knows that the first 4 bits of plaintext are 1000. (a) Based on this information, what are the first 4 bits of the sequence generated by the LFSR? (Note: they are not just the first 4 bits of ciphertext or of known plaintext!) (b) Use your answer to (a) to deduce the coefficients for the LFSR and decrypt the 8-bit plaintext: CO II c1 = 8-bit plaintext