Can a ACK or SEQ Number exceed a range and crash the NIC? I was watching the TCP Stream out of pure curiosity of my FTP Server and saw that the ACK and SEQ number increases by one with each sequence being transmitted successfully. I am not sure, but Wireshark won't show it, isn't there a random number before and increased by one after the 3-Way-Handshake between both communicating parties to declare if a sequence was sent/received correctly? May I ask what happens if you have a HUGE file which you want to transmit and which is cut into billions of sequences and you reach the border of 32 or even 64 Bits of this ACK and SEQ counter? Does the transmission stop and would it crash the NIC? (I could maliciously imagine to send a SEQ number starting at the very last number of the 64 Bit range...)

> of the 64 Bit range...

Sequence numbers are 32 bit only.
And they simply wrap around.