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  • Rickard Korkko thinks this is interesting:

The flags, from left to right, are Congestion Window Reduced (CWR), ECN-Echo (ECE), Urgent (URG), Acknowledgment (ACK), Push (PSH), Reset (RST), Synchronize (SYN), and Final (FIN).

From

Cover of Routing TCP/IP, Volume 1, 2/e

Note

What are the different flags in the TCP header? #TCP url:https://www.safaribooksonline.com/library/view/routing-tcpip-volume/1587052024/graphics/01fig17.gif