Network Fundamentals

“The Network is reliable.” — The 1st Fallacy of Distributed Computing

As a System Design expert, you cannot treat the network as a black box. You must assume it will fail, stall, and corrupt data. In this module, we peel back the layers of the internet.

What you will master:

  1. The OSI Model: How data moves from your keyboard to a server in Japan.
  2. TCP vs UDP: The trade-off between reliability and speed (Gaming vs Banking).
  3. HTTP/1.1 vs HTTP/2 vs HTTP/3: How the web became fast, and why “Head-of-Line Blocking” is the enemy.
  4. Real-Time Communication: Short Polling, Long Polling, WebSockets, and SSE.
  5. gRPC: The high-performance framework for internal Microservices.

This knowledge is the difference between a Junior who says “The API is slow” and a Senior who says “We have high TCP retransmission rates on the Load Balancer.”

Module Chapters