Caveat Academy course · Grades 9 to 12

Computer Networking: how the internet works

Follow one web request from your laptop to a server and back: through the layers, across a switch that learns where everyone is, out a router that picks the next hop, inside a TCP connection on port 443, after a DNS lookup that turns a name into an address. Learn to subnet by hand, read the tools technicians use and find a fault one layer at a time. Six modules at your own pace with a check in every lesson.

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$19one-time · every device you sign in on
Buy · $19

Included with the Caveat Academy pass and Whole-school licenses. Or get it in the High school electives library, $119 for 66 items.

6 modules · 18 lessonsabout 12 hours$19

Six modules, eighteen lessons

Each module ends with a practice set that tracks mastery, an explain-it-back prompt, a short written response and a module exam. The final opens when every module is proficient; passing it earns a certificate with a verification code.

  1. Module 1: How networks work

    Compare network types and topologies, compute transfer times from file sizes and speeds, and explain the layered model and encapsulation.

    • What a network is
    • Bits, bandwidth and latency
    • The layered model
    about 2.1 h

  2. Module 2: Cables, Ethernet and Wi-Fi

    Choose cable, fiber or Wi-Fi for a link, explain how a switch learns MAC addresses and plan Wi-Fi bands and channels.

    • Network media
    • Ethernet, MAC addresses and switches
    • Wi-Fi
    about 2.1 h

  3. Module 3: IP addressing

    Convert octets to binary, find network, broadcast and host ranges for a subnet, and explain private addresses, NAT and IPv6.

    • IPv4 addresses and binary
    • Subnet masks and CIDR
    • Private addresses, NAT and IPv6
    about 2.1 h

  4. Module 4: Routing and transport

    Trace how routers forward packets, compare TCP and UDP for an application, and identify services by port.

    • Routers and the default gateway
    • TCP and UDP
    • Ports and sockets
    about 2.1 h

  5. Module 5: Network services

    Explain DNS resolution, read HTTP requests and status codes, and use DHCP settings and command-line tools to inspect a connection.

    • DNS, the internet's directory
    • The web: HTTP and HTTPS
    • DHCP and the everyday tools
    about 2.1 h

  6. Module 6: Security and troubleshooting

    Evaluate threats and defenses for a network and diagnose a fault layer by layer.

    • Threats to networks
    • Defenses
    • Troubleshooting a network
    about 2.1 h

Try it before you start

This is how every lesson works: step through a worked example at your own pace, then answer a check and get the reason right away. Nothing here is saved; the course keeps your progress.

Module 6 · Troubleshooting a network

Worked example: diagnosing one laptop

  1. A laptop cannot open any website. ipconfig shows 192.168.1.40 with gateway 192.168.1.1, so addressing looks fine.

A lesson check from each module

The checks need JavaScript turned on. The course itself works the same way.

What you get

Academics · High School$19 · included with the Academy pass and Whole-school licenses

What you finish with
A finished semester of networking: you can estimate download times without mixing up bits and bytes, explain the layered model and encapsulation, choose copper, fiber or Wi-Fi for a link, explain how switches learn and routers forward, subnet an IPv4 network by hand, explain private addresses, NAT and IPv6, choose between TCP and UDP, name services by port, follow a DNS lookup and an HTTP request, read DHCP settings, and secure and troubleshoot a home network layer by layer. Passing the final earns a Caveat certificate of completion.
Who it is for
Students in grades 9 to 12 who want to know what happens when they press Enter, students thinking about IT, cybersecurity or computer science, and homeschool families who want a full semester of technology. No programming is needed; the activities use the free tools already on any computer, on networks the student owns or has permission to use.
Format
An online self-paced course: 6 modules and 18 lessons with worked examples you reveal step by step, 144 practice and exam items (multiple choice, numeric, fill-in and ordering), an explain-it-back prompt and a rubric-checked short response in every module, module exams with one retake, a 24-question final and a certificate with a verification code. About 12 hours in all; works on a phone or a computer.
Access
$19 one-time, yours on every device you sign in on; the course opens once you are signed in with it. Included with the Caveat Academy pass and Whole-school licenses. Also in the High school electives library ($119) and the Academics Suite pass ($149), and 1 more bundle. Progress is saved in this browser on this device, and the certificate page lets you download your record.
Where it lives
The High School space in Caveat Academics.
Support
Access, a receipt, a refund or a correction to the course: team@caveatacademic.com.

How it works

  1. Open the course and start Module 1. Each lesson takes about 25 to 35 minutes; two or three a week finishes the course in about a semester.
  2. Answer the checks as you read. Every answer shows the reason, and a miss links you back to the lesson that covers it.
  3. Finish each module with its practice set and exam. Proficient on every module opens the final; 70 percent passes it.
  4. Print or download your certificate and record from the certificate page.

Start the course

Sources and accuracy

The lessons are original writing by Caveat Academic Services. Facts were checked against these free, open references, which are also good places to read further.

  1. Internet Engineering Task Force standards: RFC 791 (IPv4), RFC 8200 (IPv6), RFC 9293 (TCP), RFC 768 (UDP), RFC 1918 (private addresses), RFC 2131 (DHCP), RFC 1034 and 1035 (DNS): rfc-editor.org
  2. Internet Assigned Numbers Authority, service names and port numbers registry: iana.org
  3. Cybersecurity and Infrastructure Security Agency, guidance on securing home networks, passwords and multi-factor authentication: cisa.gov
  4. MDN Web Docs, HTTP methods and response status codes: developer.mozilla.org
  5. Wi-Fi Alliance, Wi-Fi security (WPA2 and WPA3) and frequency bands: wi-fi.org

Computer Networking is a self-paced course from Caveat Academic Services. It follows the sequence of a typical high school networking course and covers ideas found in entry-level networking certifications, but it is not certification preparation, does not replace a school course and awards no credit. Addresses in examples come from ranges reserved for private use and documentation. Test only networks and devices you own or have permission to test. Support: team@caveatacademic.com.