Dive deep into the Transmission Control Protocol (TCP) with this comprehensive 44-minute video tutorial. Explore 12 key concepts that explain how TCP has served as the predominant layer 4 protocol for the Internet over the past 40 years. Learn about sequence numbers, acknowledgement numbers, window size, delayed acknowledgements, flow control, TCP connection closures, and FIN + Reset segments. Gain a thorough understanding of TCP's inner workings, including the three-way handshake, bidirectional communication, initial sequence numbers, and connection termination methods. Discover how to analyze and troubleshoot TCP connections, and explore the nuances of TCP headers and flags. Perfect for networking professionals and enthusiasts looking to enhance their knowledge of this crucial Internet protocol.
Overview
Syllabus
- Intro
- Pre-Requisites - background knowledge of TCP and UDP
- Twelve Ideas to understand TCP and the TCP Header
- Idea 1 - Sequence Numbers and Acknowledgement Numbers
- Idea 2 - Sequence & Acknowledgement Numbers are tracking BYTES sent and received
- Understanding Sequence Numbers and Acknowledgement Numbers
- Idea 3 - TCP Retransmission Timer
- Idea 4 - Delayed Acknowledgements - Acknowledgments are Cumulative
- Idea 5 - Window Size and Bytes in Flight
- Delayed ACKs vs Window Size
- Idea 6 - Window Size, TCP Headers and Flow Control
- Idea 7 - TCP is Bidirectional - both peers have SEQ# and ACK#
- Empty Acknowledgements, Duplicate Acks, TCP analysis, TCP troubleshooting
- Idea 8 - Initial Sequence Numbers ISNs are Random
- Idea 9 - TCP Three Way Handshake - SYN, SYN ACK, ACK
- 3-way Handshake, SYN flags, ACK Flags, and the TCP Header
- Initial Window Size is set in the three-way handshake
- SYN packets increase the Sequence Number -- The Phantom Byte
- ACK flag is turned on for all TCP segments, except the initial SYN
- Idea 10 - Two methods for TCP to close a connection - FIN and RST
- Idea 11 - FIN Flags and Four Way Connection Closure
- FIN Flags do not need to be sequential
- Phantom Byte inside the FIN and SYN Segments
- Idea 12 - RST Flags instantly terminate a TCP connection
- Want more? Help me blow up these videos and I'll create the full TCP Masterclass
- Networking - The Internet, the Cloud, and everything in between
Taught by
Practical Networking
