A beginner-friendly walkthrough of the TCP 3-way handshake, covering each step: SYN, SYN-ACK, and ACK. Explains the role of control flags and initial sequence numbers (ISNs), why ISNs are randomized for security, and briefly touches on whether the internet is moving away from TCP toward QUIC with HTTP/3.

3m read timeFrom newsletter.systemdesigncodex.com
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Table of contents
1 - SYN (Synchronize)2 - SYN-ACK (Synchronize Acknowledge)3 - ACK (Acknowledge)FAQs
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