TCP Deep Dive: TCP SYN Cookies, The What, The Why, and The How
What if a simple packet(s) could bring down the internet? In the world of TCP/IP, vulnerabilities like SYN flood attacks have threatened network stability for decades. This deep dive explores the ingenious mitigation known as TCP SYN cookies, from the basics of TCP state management to its pragmatic trade-offs and lessons for modern engineering. Transmission Control Block The Transmission Control Block (TCB) is a critical data structure created when a TCP entity opens a TCP connection. A TCB contains the whole state of the connection and must maintain all information required to send and receive segments. ...