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Free module

Networking in practice

Networking in practice: IP addresses and ports, DNS, HTTP and TLS, NAT, proxies and load balancers, and troubleshooting a connection.

6 lessons300 min lesson

The lessons

Each lesson is free to read in full. Create a free account to run its commands in a live lab and to sit its quizzes and tasks.

  1. 1

    IP addresses and ports

    I can say what an IP address and a port are.

    Read the lesson

  2. 2

    How a name becomes an address

    I can explain how a name becomes an address.

    Read the lesson

  3. 3

    What HTTPS protects

    I can explain what HTTPS protects.

    Read the lesson

  4. 4

    Servers in the middle: proxies and load balancers

    I can say what a proxy, a reverse proxy and a load balancer do.

    Read the lesson

  5. 5

    Sharing one public address

    I can explain how many devices share one public address.

    Read the lesson

  6. 6

    Finding where a connection fails

    I can use ping and traceroute output to find where a connection fails.

    Read the lesson

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