I launched an EC2 instance in Tokyo region (ap-northeast-1) . Opened a browser. Typed the public IP. The page loaded in milliseconds.

But I couldn't stop thinking — how did that packet find my EC2? Out of millions of servers inside AWS datacenters, how did my HTTP request land on exactly the right physical machine?

So I ran some experiments. What I found was a journey across three completely different networks — each with its own rules, its own routing logic, and its own way of saying — The EC2 you want is this way👉

Let me walk you through all of it.

The Setup

Before we trace the packet, here is the EC2 instance I used for this experiment.

The Big Picture — Three Stages — Three Networks

Stage 1 — Public Internet

Stage 2 — AWS Private Backbone

Stage 3 — Inside the Physical Server

Each stage has a completely different routing mechanism.…