Error Detection and Correction: Cyclic Redundancy Check
Consider the Cyclic Redundancy Check (CRC) algorithm discussed in Section 6.2.3 of the text. Suppose that the 4-bit generator (G) is 1001, that the data payload (D) is 10011111 and that r = 3.
Question List
1. What are the CRC bits (R) associated with the data payload D, given that r = 3?
Solution
To compute the CRC, we begin by taking the value of D, 10011111, and multiplying it by 2^3, giving 10011111000.
We then divide this number by the generator bits [G] = 1001, using modulo-2 arithmetic. The final remainder, R, after
this division are then the CRC bits. Here is that calculation:
We've computed the remainder as R = 110 and the quotient n = 10001110. You should verify that n*G XOR R is indeed equal
to 10011111000. You can use this calculator to do the
modulo-2 arithmetic if you don't want to do it by hand.
That's incorrect
That's correct
The answer was: 110