{TAIL ~ The combination} of the FEC value 515, {HEAD ~ the data block} 500A, the FEC value 515′ and the data block 500A′ is the adaptive response 505A by the retransmit server 110A to the repair server 120A 
{ TAIL ~ The combination } of the FEC value 515 , { HEAD ~ the data block } 500A , the FEC value 515′ and the data block 500A′ is the adaptive response 505A by the retransmit server 110A to the repair server 120A
TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH