Step 1
Learning path
Computer Networking Roadmap for Beginners
Networking fundamentals in the order a network engineer learns them, taught by doing: a browser Linux terminal for the commands, the OSI model layer by layer, IP addresses and subnet masks worked by hand, then DNS lookups, ports and sockets, ping, HTTP requests typed by hand and TLS on real hosts, and a lab where you address and fix a LAN. Free, with a certificate for each course.
35,201+ codders enrolled across these courses
282 lessons264 challenges776 quiz questions
- Beginner friendly
AI-assisted coding help
Hands-on interactive lessons
Audio narration on every lesson
Quizzes to test your knowledge
6 free certificates along the path
The computer networking path, step by step
Each step is an existing Coddy course. Take them in order, or jump into the one you are missing - your progress is saved per course either way.
- 1
- 2Step 2
The OSI model, layer by layerDedicated page
Start this stepStartThe seven layers and what actually lives at each one - frames, packets, segments, ports, protocols - with the TCP/IP model beside it. The vocabulary every later course, every job interview and every troubleshooting session uses.StartDedicated page - 3Step 3
IP addressing and subnettingDedicated page
Start this stepStartIPv4 addresses, classes and CIDR, subnet masks, network and broadcast addresses, splitting a network into subnets and sizing them - worked by hand with instant checking until the arithmetic is automatic. The step most networking students fail and the one this path drills hardest.StartDedicated page - 4Step 4
Networking with the terminalDedicated page
Start this stepStartHow hosts talk, names and DNS, ports and sockets, reachability checks, then HTTP typed by hand, curl in depth, sending data, HTTPS and TLS, and debugging authentication - on real hosts. This is how an engineer actually looks at a network from the command line.StartDedicated page - 5Step 5
LAN labsDedicated page
Start this stepStartAddress the hosts on a LAN, get the masks right, add routers and gateways, troubleshoot what does not connect, then grow the office network and fix a broken branch. The lab where the previous three steps become one skill.StartDedicated page - 6Step 6
Docker and container networkingDedicated page
Start this stepStartImages, containers and Dockerfiles, then the part most Docker courses skip: how containers get addresses, talk to each other and reach the outside world. The bridge from networking fundamentals into DevOps and cloud work.StartDedicated page
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1const greeting = "Hello, Coddy!"
2function sayHi(name) {
3 return greeting + " " + name
4}
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"Hello, Coddy! Alex"
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Intro to Variables
Audio
A variable is a named container that stores a value you can reference later in your program.
In Python, you create one by writing the name, an equals sign, then the value you want to store.
The value can change over time - reassigning the name simply points it to a new value.
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Certificate of CompletionThis certifies thatJohn Doehas successfully completedPython Fundamentals
Python Fundamentals
DateJan 2026
Add to LinkedInWhy learn computer networking on Coddy
- A real terminal, not a diagram. Networking is usually taught from slides; here you run ping, DNS lookups and curl against real hosts in your browser and read the raw HTTP that comes back, so every concept is something you have watched happen.
- Subnetting worked by hand until it is easy. Address classes, CIDR, masks and broadcast addresses are the part of every networking course people fail; this path drills them with instant checking until they are arithmetic, not memory.
- AI hints that read your command and its output. When a gateway is missing or a mask is wrong, Bugsy looks at what you typed and what came back and nudges you toward the fix without handing over the answer.
- One free certificate per course, verifiable at its own URL: Linux, the OSI model, subnetting, network tools, LAN labs, Docker - each a line on a CV a hiring manager can test in five minutes.
Frequently asked questions about learning computer networking
What are the basics of computer networking I should learn first?
How devices are addressed (IP addresses, subnets, MAC addresses), how data is layered on its way across a network (the OSI and TCP/IP models), how names become addresses (DNS), how a packet finds its way (routing and switching), and the handful of commands that let you see all of it happening. That is this path, in that order, with the command line first because every tool that follows runs in one.
Is this a CCNA course?
No, and we would rather say so than pad the page. CCNA is Cisco's certification, with its own exam blueprint and vendor-specific configuration. This path is the hands-on half that CCNA study assumes you already have: addressing, subnetting, the models, the terminal tools and a working LAN. Many people take it before a CCNA book so the book's diagrams describe things they have already seen.
Can I learn networking without buying routers and switches?
Yes. Everything on this path runs on real Linux hosts in your browser: you query DNS, check reachability, open sockets, send HTTP requests by hand and inspect TLS without owning a single piece of hardware. The LAN lab addresses, routes and troubleshoots a network the same way. Physical gear teaches cabling and vendor menus, which come later and quickly once the concepts are solid.
Do I need to know Linux before learning networking?
You need the command line, which is why it is step one here. Almost every networking tool worth knowing - ping, DNS lookups, curl, the port and socket tools - is a terminal command, and most network engineering, DevOps and security work happens on Linux servers. A week or two in the terminal course is enough to make the rest of the path comfortable.
How long does it take to learn networking fundamentals?
Around two to three months at an hour a day for the full path: two weeks for the terminal basics, two to three for the OSI model, three to four for IP addressing and subnetting until it is automatic, three for the terminal networking course and the LAN labs together, and two for Docker networking. Subnetting is where most people spend the most time and where the practice pays off most.
What jobs use these networking skills?
Network engineer and network administrator most directly, but also every DevOps, site reliability, cloud and security role: containers, cloud VPCs, load balancers, firewalls and VPNs are all networking with a product name on top. Backend developers who can read a raw HTTP exchange debug production problems that stump their colleagues. The Docker step at the end is the bridge into the DevOps path.
Is this networking course free?
Every course on the path is free: the lessons, the in-browser Linux terminal, the labs, the AI hints and the certificate at the end of each course. Pro removes the daily energy limit and adds unlimited AI help; nothing on this page is locked behind it.
