The FEC processor computes an FEC value {HEAD ~ 515′} on {TAIL ~ the data} block 500A′ and appends it to the data block 500A′ 
on
The FEC processor computes an FEC value { HEAD ~ 515′ } on { TAIL ~ the data } block 500A′ and appends it to the data block 500A′
OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH