ns-3 is a discrete-event network simulator for Internet systems, targeted primarily for research and educational use. ns-3 is free software, licensed under the GNU GPLv2 license, and is publicly available for research, development, and use.
ns-3 is intended as an eventual replacement for the popular ns-2 simulator. The domain name acronym “nsnam” derives historically from the concatenation of ns (network simulator) and nam (network animator).
Latest stable release: ns-3.11 (May 25, 2011)
Older releases: See the downloads page.
ns-3.12 is scheduled for release in the fall of 2011. The summary ns-3 roadmap lists some future release plans.
Public development efforts are being tracked at this page. Our main development tree is the ns-3-dev repository. Please see our Getting Started page for how to work from the development branch.
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Monthly download count of ns-3 releases | Cumulative lines of code changed over time |
Building a great network simulator for research and education requires many contributions from the networking community. We outline the many ways that users can contribute on our Contributing web page.