AWS S3: You're out of order. - Signal v. Noise

How does a TCP sender recognize out-of-order ACK packets In regards to ACK'ing out of order packets, this is done through SACK as described in this PacketLife post. EDIT: After reading your edited question I believe TCP timestamps are the answer you're looking for. TCP timestamps are used in an algorithm known as Protection Against Wrapped Sequence numbers, or PAWS (see RFC 1323 for details). Palo Alto Networks TCP Settings and Counters Apr 20, 2020

How does wireshark determine if a TCP packet is out-of-order?

TCP out of order arrivals and ack numbers - YouTube Jan 15, 2017

TCP Keep-Alive. Set when the segment size is zero or one, the current sequence number is one byte less than the next expected sequence number, and any of SYN, FIN, or RST are set. Supersedes “Fast Retransmission”, “Out-Of-Order”, “Spurious Retransmission”, and “Retransmission”. TCP Keep-Alive ACK. Set when all of the following

Application Performance Monitoring: Out of Order Packets In the past, it has been a challenge to setup specialized applications and tests to identify if poor application performance is being caused by out of order packets. Out of order packet delivery is when when the delivery of data packets on a computer network is different from the …