If you ask most people where to start in DevOps or cloud engineering, you'll get answers like "learn Docker" or "get AWS certified." Almost nobody says "learn networking first," and that's a mistake — because every one of those tools sits directly on top of networking concepts, and skipping it means you're memorizing commands without understanding what they actually do.
I hit this wall myself. I could docker run things and get a VPC "working" by copy-pasting a tutorial, but the moment something broke — a container that couldn't reach another container, a service that was unreachable from outside a cluster, a security group that silently ate my traffic — I had no mental model to debug with. So I went back and actually built one, layer by layer, from a single IP address up to how Kubernetes routes traffic across a cluster. This post is that mental model, written the way I wish someone had explained it to me first.
Start With the Absolute Basics
IP Address — the identifier for a device or server on a network. Every machine that wants to send or receive data needs one, the same way every house needs an address for mail to find it.
DNS (Domain Name System) — the system that maps human-readable domain names to IP addresses. You type google.com, your machine asks a DNS server "what's the IP for this," and gets back something like 142.250.183.14. Nobody memorizes IP addresses; DNS is the reason you don't have to.
