Send Data That Contains Data to Be Retransmitted
The following figure shows how the SndUna, SndNxt, and SndMax members of the TCP_OFFLOAD_STATE_DELEGATED structure segment send data that contains data to be retransmitted by the offload target.
The data from the byte that is indicated by SndUna up to the byte before the byte that is indicated by SndNxt is data that the host stack transmitted but for which the host stack did not receive an acknowledgment from the remote host. The offload target must process any acknowledgments for this data and retransmit the data later, if necessary.
The data from the byte that is indicated by SndNxt up to the byte that is indicated by SndMax is data that the offload target must send next on the TCP connection after the connection has been offloaded. This data is data that might have to be retransmitted. The offload target must send this data before sending any other data on the offloaded connection.
The data to the right of the byte that is indicated by SndMax is unsent data that the offload target must send after sending the data to be retransmitted.