Why Knowing TCP’s Three‑Way Handshake and Four‑Way Teardown Isn’t Enough
The article explains TCP’s three‑way handshake and four‑way termination in depth, describes each state and flag, shows how kernel parameters affect behavior, and provides practical commands and troubleshooting steps for common issues such as TIME_WAIT overload, CLOSE_WAIT accumulation, SYN floods, and connection resets.
