See the network you’re building.
Connect routers, switches, and hosts on a visual canvas. Open a device and make your configuration count.
Explore network simulation
Online network simulator
Build network labs.
In your browser.
Practice network CLI, troubleshoot connections and test supported network behavior in an online simulator. Start with a topology. Learn without a hardware rack.
7 days free No credit card Nothing to install
192.168.10.0 / 24
R1 · Edge router
R1# show ip interface brief
Interface IP-Address Status Protocol GigabitEthernet0/0 192.168.10.1 up up GigabitEthernet0/1 10.0.0.1 up up
Select a device to explore sample CLI output.
YOUR NEXT CHAPTER STARTS WITH PRACTICE
network CLIGuided learningNetworks & IoT
Your lab goes with you
Open a browser and get to work. No rack space, VM setup, or hardware to carry.
Make the connections
Turn a network diagram into a working topology. Add devices and connect your ideas.
Learn at the command line
Practice network commands and investigate how your configuration changes the network.
THE WORKSPACE
Less setup.
More discovery.
A place to turn networking theory into practical skills. Build, configure, and troubleshoot from one connected workspace.
Get fluent in network CLI.
Move past memorizing commands. Configure interfaces, check routing, and see what happens next.
Router(config)# interface g0/0
Router(config-if)# no shutdown
Router(config-if)# no shutdown
Make mistakes here.
Build confidence everywhere.
Investigate a broken connection. Challenge an assumption. Practice your troubleshooting process in a simulated environment.
CHOOSE YOUR NEXT CHALLENGE
Network practice with a purpose.
Start with the question you want to answer. Find a workflow that fits your learning or engineering task.
Practice network configuration
Build a topology, open the CLI and investigate routing and switching in a browser-based simulator.
Explore this workflowTest a network design
Turn a routing or connectivity question into a repeatable test, with clear expectations and documented limits.
Explore this workflowLearn through guided labs
Find published scenarios, follow tutorials and explore practical assessments as they become available.
Explore this workflowExplore connected devices
Follow an MQTT message from a simulated sensor through a broker to its subscriber.
Explore this workflowA PATH THROUGH THE PRACTICE
Discover. Learn. Prove it.
Start with a scenario, build understanding step by step, and find out what you can do on your own.
01 / DISCOVER
Marketplace
Find a lab with a purpose. Browse network scenarios and course content, then bring a published lab into your workspace.
Explore Marketplace02 / PRACTICE
Tutorials
Turn a concept into a working configuration. Follow guided tasks, verify supported checkpoints, and see your progress.
Explore tutorials03 / ASSESS
Examinations
Put your lab skills to the test. Final assessments check your work and highlight the course topics to revisit.
How examinations workContent and assessments become available as they are published. Access depends on the selected pack and your plan.
IoT SIMULATION
Small sensors.
A whole connected world.
Connect simulated sensors, MQTT brokers, and subscribers. Follow telemetry across your topology and explore how connected devices communicate.
Explore IoT simulationsIoT features require an eligible Enterprise plan.
MQTT / PUBLISH–SUBSCRIBEEXAMPLE
SensorPublish
BrokerRoute a topic
SubscriberReceive
lab/room/temperature
22.4 °CFROM IDEA TO INTERFACE
Your first lab starts here.
Make yourself at home
Create an account and start your free 7-day trial. No credit card required.
Build your topology
Place your devices on the canvas and connect them to bring your lab idea to life.
Open the CLI. Get curious.
Configure, inspect, and troubleshoot. Connect what you’ve learned to what the network does.
BEFORE YOU START
Know your lab.
A clear picture of what you can practice, what access you need and where simulation ends.
Is nuLAB a simulator or an emulator?
nuLAB is a browser-based network simulator. It models supported commands and network behavior rather than running proprietary network operating-system images. Its standard offering does not provide those images. Understand the simulation model.
Can I use it to validate a network design?
You can investigate supported configuration, routing and connectivity behavior in a simulated topology. Record the assumptions and expected results for each test. Simulation does not establish exact hardware performance, complete feature parity or production readiness. Plan a scoped validation exercise.
Are tutorials, examinations and IoT included in every plan?
Access depends on your plan and the content that has been published. Marketplace packs can have separate entitlements; examinations require published assessment content. IoT features require an eligible Enterprise plan. Explore learning and device availability.
When do I still need physical hardware?
Use appropriate hardware or an authorized environment to verify hardware-specific behavior, throughput, optics, platform licensing and other requirements the simulator does not model. Read the platform disclaimer.
FROM THE PORTAL
A lab that keeps evolving.
Portal release update
Explore the changes published for this release in the portal’s full technical notes.
- added 2
- improved 2
- fixed 4
- Other updates 1
Safer platform restarts
Planned shutdowns notify connected users, finish admitted work and save loaded labs before the service stops. Network service configuration and address handling also improve.
- added 1
- improved 1
- fixed 2
More reliable saved configurations
Targeted configuration removal preserves unrelated settings. Guided reload checks distinguish missing configuration from unavailable evidence.
- improved 1
- fixed 2
FIELD NOTES
A little perspective.
A lot to explore.
THE NEXT MOVE IS YOURS
Learn it. Build it.
Make it click.
Your next networking breakthrough starts with a little hands-on practice.