A systematic group code C is a code over G ^ n of order \ left | G \ right | ^ k defined by n-k homomorphisms which determine the parity check bits.
12.
The control information encapsulates an 8 bit sideband ( used by higher layers for framing ), sequence numbers ( for go-back-n link-layer retransmissions ) and check bits ( CRC-16 ).
13.
A "'parity bit "', or "'check bit "', is a bit added to a string of binary code to ensure that the total number of 1-bits in the string is error detecting code.
