ns-3
ns-3: A free, research-focused simulator with broad network models and desktop-based workflows. Ranked #6 of 30 in Network Simulation Software by our editors (8.7/10); pricing: Free plan; best for open-source discrete-event research.
At a glance
- Editor score8.7 / 10
- PricingFree plan
- Best forOpen-source discrete-event research
- Free planYes
- Paid fromFree
- Real-time emulationYes
- Founded2006
- Facts checked20 Sep 2026
Where it wins
- Free and open source for research and education
- Broad wireless, IP, routing, mobility, and device models
- Real-time, tracing, visualization, and MPI support
Where it doesn't
- Desktop deployment without a web interface
- Scenario development uses C++ or Python programs
- Integrations are limited to a focused set of tools
Our verdict on ns-3
ns-3 is a free, open-source discrete-event network simulator for Internet systems. It is aimed primarily at networking research and education, supporting models for IP and non-IP networks, wireless technologies, routing, applications, mobility, and network devices. Users create simulation scenarios with C++ or Python, then examine packet traces, visualize network behavior, run distributed simulations, or connect simulations to real systems through real-time and emulation capabilities.
There is no paid tier structure to compare: ns-3 is available as open-source software with a free plan. Its scope is broad for research workflows, combining discrete-event simulation with a real-time scheduler, simulation-in-the-loop operation, interaction with real network devices, packet tracing, pcap output, NetAnim topology and packet-flow visualization, and MPI-based distributed simulation. This makes it suitable for teams that need to model network behavior in detail rather than manage simulations through a commercial dashboard.
Platform fit is centered on desktop environments, with support for Windows, macOS, and Linux. The project connects with BRITE, Click Modular Router, MPI, and OpenFlow, while automation is supported through C++ scripting, Python bindings, and simulation scripts. The trade-off is a focused ecosystem: ns-3 does not provide a web interface, and its listed integrations are limited. Choose it for open-source network research, education, wireless and routing studies, or scenarios that require tracing and real-system interaction. A different tool may suit teams seeking browser-based operation or a broader integration layer.
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ns-3 pricing
ns-3 fact sheet
| Free plan | Yes |
|---|---|
| Paid from | Free |
| Simulation model | Discrete-event |
| Real-time emulation | Yes |
| Hardware-in-the-loop | Not verified |
| Deployment options | Desktop |
| Documented node limit | Not verified |
| Automation API | Yes |
| Deployment | Desktop |
| Platforms | Windows, macOS, Linux |
| Support | Community, Docs |
| Built for | Solo, Small business, Mid-market, Enterprise (editorial estimate) |
| Integrations | 4 integrations: BRITE, Click Modular Router, MPI, OpenFlow |
| Pricing | Free plan |
| Website | nsnam.org |
| Facts checked | 20 Sep 2026 |
ns-3 integrations
ns-3 lists 4 integrations on its own site.
- BRITE
- Click Modular Router
- MPI
- OpenFlow
Alternatives to ns-3
- GNS3A free, broad multivendor lab for simulating, emulating, and connecting real networks.9.4
- Cisco Modeling LabsA Cisco-focused virtual lab with broad automation, integration, and deployment options.9.2
- EVE-NGA broad emulation platform for large, collaborative multivendor network labs.9.0
ns-3 vs the competition
- ns-3 vs GNS3
- ns-3 vs Cisco Modeling Labs
- ns-3 vs EVE-NG
- ns-3 vs NetSim by Tetcos
- ns-3 vs OMNeT++
- ns-3 vs Containerlab
Compare ns-3 with any tool side by side →
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Reviewed by iTechGuides Editors · Editorial team · Updated Oct 2026
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