Learn Networking

Follow data from a local link to the services that power the web.

Start learning 7 lessons · about 2 hours · free
About this track

Learn how networks move data: start with layers and Ethernet, then explore IPv4, subnets, routing, TCP, UDP, DNS, HTTP, and TLS. Short Python simulations make the ideas concrete. Exercises run in your browser and do not send network traffic.

Before you start
  • No networking or programming experience needed.
  • A modern browser with JavaScript enabled.
  • The first exercise run loads the Python runtime in your browser.
  1. Unit 1 · 0/3 lessons

    Network foundations

    Meet protocol layers, frames, and IPv4 networks. Badge: Packet mapper

    1. 0x001Understand network layersSee how protocols divide a message into manageable jobs. 15 min 0/1 exercises solved 15 min 0/1 exercises solved
    2. 0x102Deliver frames on a local networkDistinguish link-layer addresses from network addresses. 15 min 0/1 exercises solved 15 min 0/1 exercises solved
    3. 0x203Read IPv4 addresses and prefixesUse a network prefix to identify addresses in the same subnet. 15 min 0/1 exercises solved 15 min 0/1 exercises solved
  2. Unit 2 · 0/2 lessons

    Routing and transport

    Forward packets and compare TCP with UDP. Badge: Route finder

    1. 0x304Choose a route for a packetFollow next hops and understand longest-prefix matching. 15 min 0/1 exercises solved 15 min 0/1 exercises solved
    2. 0x405Compare TCP and UDPLearn what transport protocols add above IP. 15 min 0/1 exercises solved 15 min 0/1 exercises solved
  3. Unit 3 · 0/2 lessons

    Network services

    Resolve names and trace a request to a web server. Badge: Web navigator

    1. 0x506Resolve names with DNSFollow the lookup from a name to a network address. 15 min 0/1 exercises solved 15 min 0/1 exercises solved
    2. 0x607Follow a web request safelyConnect DNS, transport, HTTP, and TLS in a browser request. 15 min 0/1 exercises solved 15 min 0/1 exercises solved
Did you like the lesson? 😆👍
Consider a donation to support our work:
See donation links