1. The SYN is followed by the packet number at which to restart. 2. In the meantime the receiver receives packet numbers 5 and 6. 3. When the receiver receives packet number 6, it sends yet another acknowledgement value of 2. 4. If packet number 39 is the last to arrive, the receiving computer will sort things out. 5. After receiving packet number 5, the receiver sends an acknowledgement, but still only for sequence number 2. 6. At the destination, the original message is reordered based on the packet number to reproduce the original message. 7. Again, a normal XMODEM implementation would simply discard the packet, the assumption being that the packet number had been corrupted. 8. If the packet number was missing, it was assumed it was sending to a non-SEAlink XMODEM, and set the window size to one. 9. Headers include information like " This is packet number X, coming from Y, going to Z, and has Q numbers of characters in it. 10. On reception of the very first ACK or NAK, the SEAlink sender would " notice " the packet number and continue to use windows.
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