Networking, explained through practice.
Explore routing, switching, and network security with clear explanations, topologies, and practical verification. Follow each topic from its first concept to focused configuration and troubleshooting lessons.
Understand the concept
Begin with a network and a question. Learn the behavior before changing the configuration.
Apply it to routers
Follow named devices and relevant examples, with diagrams that explain the connections.
Check the result
Connect router actions to the results shown in command output and packet examples.
Routing & Switching
Explore routing protocols one focused lesson at a time.
Open Shortest Path First
Neighbors, link-state information, areas, and path calculation.
View course →Intermediate System to Intermediate System
Adjacencies, routing levels, link-state databases, and resilience.
Security
Protect network links and inspect traffic with dedicated security tracks.
A focused learning sequence
Choose a topic in the sidebar and work through its sections one lesson at a time. Each lesson develops a specific concept and points to the next step.
All seven BGP units are available: 55 lessons and a final hands-on lab, with takeaways and quizzes. Open the OSPF, MACsec, or Suricata course overview to see its lesson availability. Unfinished topics are marked Planned.