Question

When a transmitted sequence and generator polynomial given for check sum, how to find actual data to be transmitted?

Answer 1

Polynomial codes for error detectionAlso called CRC (Cyclic Redundancy Check) 
Data is sent with a checksum. 
When arrives, checksum is recalculated. Should match the one that was sent.

Bitstring represents polynomial. 
e.g. 110001 represents: 
1 . x5 + 1 . x4 + 0 . x3 + 0 . x2 + 0 . x1 + 1 . x0 
= x5 + x4 + x0

The order of a polynomial is the power of the highest non-zero coefficient. This is polynomial of order 5.

Special case: We don't allow bitstring = all zeros.
Easy to use framing or stuffing to make framed-and-stuffed transmission never all-zero,
while still allowing payload within it to be all-zero.