Frontend Labs
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Series Β· step 2a

The OSI Model, One Click at a Time

One real request, followed through all seven layers. You click "Place order" on a shopping site from your laptop on home Wi-Fi. About 250 ms later you see "Order confirmed".

21 chapters Β· 1 h 7 min of reading

Contents

21 chapters, one page each. Prefer one long page? Read the whole book on one page.

  1. How to read this guide1 min
  2. The series: OS β†’ networking β†’ security β†’ HTTPS2 min
  3. Table of contents1 min
  4. Part 1 β€” The scenario2 min
  5. Part 2 β€” The mental model4 min
  6. Part 3 β€” Layer 1: Physical5 min
  7. Part 4 β€” Layer 2: Data Link6 min
  8. Part 5 β€” Layer 3: Network6 min
  9. Part 6 β€” Layer 4: Transport7 min
  10. Part 7 β€” Layer 5: Session5 min
  11. Part 8 β€” Layer 6: Presentation5 min
  12. Part 9 β€” Layer 7: Application6 min
  13. Part 10 β€” The full replay: a millisecond timeline2 min
  14. Part 11 β€” X-ray of one packet2 min
  15. Part 12 β€” Inside the server: from the NIC to your handler2 min
  16. Part 13 β€” The return trip and the goodbye1 min
  17. Part 14 β€” Debugging by layer: the incident playbook3 min
  18. Part 15 β€” Architecture decisions by layer: the senior and manager view3 min
  19. Part 16 β€” Cheat sheet2 min
  20. Part 17 β€” Self-check questions4 min
  21. Continue the series1 min

Generated from real-life-example-osi.md Β· 8 Oct 2026 16:36