Current Development

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Main Page - Current Development - Developer FAQ - Tools - Related Projects - Project Ideas - Summer Projects

Installation - Troubleshooting - User FAQ - HOWTOs - Samples - Models - Education - Contributed Code - Papers

On this page, we will try to summarize current ns-3 development work. If you are interested in collaborating on one of these projects, or reviewing work by others, please do not hesitate to contact the individuals identified, or the page maintainer.

There are a few other places to look for current activity on ns-3 development:

  • the current release page will list code under consideration for merging, and bugs being worked. The next release, ns-3.30 release, is not yet scheduled.
  • we should have entries for all of our known bugs in the Bugzilla bug tracker.
  • Related projects list some active and past projects that are associated with ns-3.
  • We maintain a suggested project ideas page for people interested in trying to start something new, or finish off some existing work.
  • We conduct code review discussions on the Google Group 'ns-3-reviews'

How to get involved

ns-3 always can use more time and assistance from contributors of all skill levels. One of the best ways to learn a tool is to try to get involved in its development processes, even if it is as simple as pointing out stale information or documentation on our web pages. Ideas on how to get started are on our project ideas page.

If you are new to ns-3 and want to contribute code, please read these guidelines: Contributing to ns-3 and review the information on this page below.

Note: ns-3 developers sometimes hang out on IRC at #ns-3 at IRC logs

Also, please check out the Current events page to learn of upcoming events for ns-3.

Code reviews

All new code (other than maintenance code committed directly by a module's maintainer) goes through a public code review. The process is described here. This page is devoted to listing code reviews that have been publicly announced.

Currently open code reviews should be also tagged in our bug tracker:

Some older code reviews can be found here (some of these have been included in ns-3, some are still pending):

Some older code reviews can be found here:



See the ns-3.30 page for the current release planning and roadmap.

Current development for main trunk of ns-3

This section is intended to list items that people are working on, to avoid duplicated efforts and to promote collaboration.

Wi-Fi 802.11ax support

Sebastien Deronne has been adding 11ax rates and support for information elements (HeOperation, HeCapabilities). He recently added a 'HeConfiguration' object to store 11ax configuration items. He is next planning to refactor the WifiPreamble class to more cleanly add support for HE-SIG-A fields.

A team at UW is working on spatial reuse features (Non-SRG OBSS_PD level) and next plans to work on MU-OFDMA aspects. The UW team is collaborating with Stefano Avallone who is working on MU-OFDMA and plans to publicly develop on his 'wifi-next' branch:

Development is planned based on the spec framework

Others are welcome to list their work in progress here regarding 802.11ax, to reduce duplicated effort and encourage collaboration. Contact one of the above maintainers if interested.

WiFi models

Wi-Fi maintainer Sebastien Deronne and others are currently working on the following list of extensions to ns-3 WiFi models:

  • WiFi channel scanning (Tom Henderson and Muhammad Iqbal)
  • Minstrel-Blues rate control (Matias Richart)
  • 802.11ad support (Hany Assasa and Sébastien Deronne)
  • 802.11ah support (Le Tian and Sébastien Deronne)
  • 802.11ax features (see above)
  • Rohan Patidar and Tom Henderson are preparing for code review a new OFDM error model based on link-to-system mapping and fast fading channels (see WNS3 2017 paper on this topic for more information)

The following additional work is recommended (contributions from others are recommended); contact Sebastien to coordinate:

  • 802.11n/ac beamforming support
  • 802.11ac MU-MIMO support
  • 802.11 HCF/HCCA
  • Any other 802.11n/ac missing feature


Last updated: Dec. 2017

Stefano Avallone is working on:

- introduce other qdiscs: fifo, prio and token bucket (Surya’s GSoC). Finish off HHF (the other qdisc Surya worked on).

- merge a few pending code reviews which implement other qdiscs (REM, BLUE, PI, PI2) and add ECN support to CoDel and PIE.

- help Pasquale and Tommaso to merge the netmap netdevice (SOCIS)

- if time permits, implement the Diffserv to IEEE 802.11 mapping as defined by draft-ietf-tsvwg-ieee-802-11-09

CSMA model

This was a feature goal for ns-3.23 release, but has slipped (further input wanted).

There has been discussion in the June 2014 timeframe about improving this model:

Some previous code reviews:

Latest patch:

These improvements have been recommended:

  1. Implement backoff counter decrement as a function of line state (see this initial code review)
  2. Divide CSMA implementation between CSMA/CD & CSMA/CA (which are totally different)
  3. Implement a distance system (not the same propagation delay for every nodes); see Vedran Miletić's work code review issue
  4. Audit the ns-3 examples to find instances where CSMA is being used with inappropriate link delay (where multiple access may perform very suboptimally)

Past development efforts

Most of these activities are now dormant or concluded and some of the information is stale.   
We are keeping here as a placeholder until this section can be cleaned up.

ns-3 core

Multi-threaded simulation implementation for multicore

Linux namespaces and ns-3

Device and channel models

Optical network: WDM, PON and RoF

See Optical network models.

Miscellaneous wifi enhancements

Patch to pause and resume an interface

Wireless Interference (Jamming) Model

Vehicular Ad Hoc Networks (VANET)

  • summary: Michele Weigle's group is working on VANET and has posted a patch for review in the past, but has taken it off the table for ns-3 merge consideration until more work is done.
  • code location: None publicly posted at this time.

Wireless Sensor Networks (i.e., 802.15.4 + 6LoWPAN + RPL)

Tommaso Pecorella announced his plans here

Current status is:

  • RPL implementation (storing, multicast): 5th refactoring going on. Moving responsibility to ParentSet and MeasureCollectors for metrics other than HC.
    • RPL is based on ROLL RFCs and drafts
    • Objective functions implemented are of0 and minrank-hysteresis-of
  • 6LoWPAN has been merged in ns-3-dev and will be included in ns-3.19.
  • 802.15.4 will rely on the lr-wpan module (currently being implemented by Boeing).
    • A patch to the lr-wpan code to enable its use with 6LoWPAN (and the full IPv6 stack) has been created. The patch adds a number of functionalities to the module and will be either included in lr-wpan or provided as a separate patch.

A wiki page will be created before 3.19 release to explain in detail the current implemented functionalities, the models limitations, the work status and provide a guide to setup a simple simulation.

Boeing is working on lr-wpan (IEEE 802.15.4-2006) support; details here.


In addition to the LENA project above, several developers expressed their interest in enhancing the LTE code initially developed within the GSoC 2010:

  • Leo Razoumov announced possible interest in the following contributions:
    • MIMO
    • PHY model abstractions
    • scheduling models
    • mobility and traffic models
  • Giuseppe Piro and his group (DEE, Politecnico di Bari) announced the intent to continue with the development of the LTE module, focusing mainly on the following MAC layer aspects:
    • RRM
    • scheduling
    • AMC
  • Marco Mezzavilla and his group (DEI, University of Padova) announced interest in working on the following, and have posted a repository in February 2011 details here:
    • MAC layer
    • mobility
    • traffic modelization
    • MIMO
  • Sandra Frei announced that a group is working on Evolved Packet System (EPS) support
    • GTPv1-U (for the user plane)
    • GTPv2-C (for the control plane)
    • Diameter: Supported use cases: default- and dedicated bearer establishment
    • NAS (ESM, EMM) A combined initial attach with a default bearer establishment. Dedicated bearer establishment
    • X2AP HO without SGW relocation. Endmarker messages are not supported

Link layer

802.21 media independent handover


Network layer

API and functionality for marking TOS bytes in packets

DSR routing

DSDV routing

Transport layer

TCP Vegas

Multipath TCP for ns-3.29 and ns-3.8

An ns-3 implementation for MPTCP (Multipath TCP). This implementation is compatible with the current ns-3 release ns-3.29.

NS-3 module for MPTCP (Multipath TCP). The current release is compatible with 3.8 version of NS-3. A check of the compatibility with the latest version is needed.

Application layer

Chord/DHash DHT

Synchronous posix/sockets API

real-world application integration

ns-3-simu sockopt patches



Jeremy Norman and the iNSpect team have posted some plans for a visualization library for ns-3:

George Riley has made a prototype animator for PointToPoint links.

Joe Kopena is working on what he calls a "decorator"

Hagen Paul Pfeifer is working on a MANET visualizer

Graphical simulation builder

Pierre Weiss and Sebastien Vincent have written an ns-3 scenario generator in Qt.


| NetExplorer is Gnome/Gtk network animation tool for NS-3.


L2 Ethernet switch module

Parallel simulations (2008)

Delay Box for ns-3

Matt Crinklaw is working on a port of ns-2 DelayBox to ns-3.

Simulation Configuration and State Detection

In order to configure simulations across multiple, probably virtualized, machines a large amount of configuration must be performed in order to construct the component systems. The oppportunity for human error to creep in during this process renders it essentially manually unworkable for all but the simplest topologies. Craig Dowell is thinking about how to address this problem.

Simulation Configuration

Build system and project infrastructure

Modular build and package management

This issue is being tracked (requirements and wish list) on this page

State of Doxygen

Need to bring Doxygen into compliance (no errors, no warnings for missing documentation).


  • investigate hooking code coverage (lcov) into the report
  • investigate how the whole buildbot farm may be made available to a maintainer to test out a non-ns-3-dev repo.

Code contribution guidance

Tom took action item to simplify and clarify the project code contribution guidelines (for people wishing to contribute new code to ns-3).

Samples directory

Consider cleanup and move of samples/ directory to examples/?


Considering to refactor documentation to split the existing manual into a model library and a software core reference manual, to add a lighter-weight tutorial, and to add a "cookbook" of howtos for common ns-3 tasks.


Status: INRIA is organizing some updates to the website.