A computer network uses polynomial over GF(2) for error checking with 8 bits as information bits and uses x3 + x + 1 as the generator polynomial to generate the check bits.
In this network, if the receiver receives 01011011101, then original message send by sender is:
(A) 01011011101
(B) 01011101
(C) 01101011
(D) 01011011
Answer: (D)
Explanation: Solving using bottom-up approach:
We add (n-1) 0’s to the LSB of dividend(message) and divided by given GF.
The remainder will be CRC, it will be added to the LSB of the original message, that should be transmitted to the receiver. That is: 01011011101.
Option (D) is correct.
Quiz of this Question