Mininet: Rapid Prototyping for Software Defined Networks

The best way to emulate almost any network on your laptop!

Mininet 2.3.1b4

What is Mininet?

Mininet emulates a complete network of hosts, links, and switches on a single machine. To create a sample two-host, one-switch network, just run:

sudo mn

Mininet is useful for interactive development, testing, and demos, especially those using OpenFlow and SDN. OpenFlow-based network controllers prototyped in Mininet can usually be transferred to hardware with minimal changes for full line-rate execution.

How does it work?

Mininet creates virtual networks using process-based virtualization and network namespaces - features that are available in recent Linux kernels. In Mininet, hosts are emulated as bash processes running in a network namespace, so any code that would normally run on a Linux server (like a web server or client program) should run just fine within a Mininet "Host". The Mininet "Host" will have its own private network interface and can only see its own processes. Switches in Mininet are software-based switches like Open vSwitch or the OpenFlow reference switch. Links are virtual ethernet pairs, which live in the Linux kernel and connect our emulated switches to emulated hosts (processes).

Features

Mininet includes:

• A command-line launcher (mn) to instantiate networks.

• A handy Python API for creating networks of varying sizes and topologies.

• Examples (in the examples/ directory) to help you get started.

• Full API documentation via Python help() docstrings, as well as the ability to generate PDF/HTML documentation with make doc.

• Parametrized topologies (Topo subclasses) using the Mininet object. For example, a tree network may be created with the command:

  mn --topo tree,depth=2,fanout=3

• A command-line interface (CLI class) which provides useful diagnostic commands (like iperf and ping), as well as the ability to run a command to a node. For example,

  mininet> h11 ifconfig -a

  tells host h11 to run the command ifconfig -a

• A "cleanup" command to get rid of junk (interfaces, processes, files in /tmp, etc.) which might be left around by Mininet or Linux. Try this if things stop working!

  mn -c

Python 3 Support

• Mininet 2.3.1b4 supports Python 3 and Python 2

• You can install both the Python 3 and Python 2 versions of Mininet side by side, but the most recent installation will determine which Python version is used by default by mn.

• You can run mn directly with Python 2 or Python 3, as long as the appropriate version of Mininet is installed, e.g.

  $ sudo python2 `which mn`
  

• More information regarding Python 3 and Python 2 support may be found in the release notes on http://docs.mininet.org.

Other Enhancements and Information

• Support for Ubuntu 22.04 LTS (and 20.04)

• More reliable testing and CI via github actions

• Preliminary support for cgroups v2 (and v1)

• Minor bug fixes (2.3.1)

• Additional information about this release and previous releases may be found in the release notes on http://docs.mininet.org.

Installation

See INSTALL for installation instructions and details.

Documentation

In addition to the API documentation (make doc), much useful information, including a Mininet walkthrough and an introduction to the Python API, is available on the Mininet Web Site. There is also a wiki which you are encouraged to read and to contribute to, particularly the Frequently Asked Questions (FAQ) at http://faq.mininet.org.

Support

Mininet is community-supported. We encourage you to join the Mininet mailing list, mininet-discuss at:

https://mailman.stanford.edu/mailman/listinfo/mininet-discuss

Join Us

Thanks again to all of the Mininet contributors and users!

Mininet is an open source project and is currently hosted at https://github.com/mininet. You are encouraged to download, examine, and modify the code, and to submit bug reports, bug fixes, feature requests, new features, and other issues and pull requests. Thanks to everyone who has contributed code to the Mininet project (see CONTRIBUTORS for more info!) It is because of everyone's hard work that Mininet continues to grow and improve.

Enjoy Mininet

Have fun! We look forward to seeing what you will do with Mininet to change the networking world.

Bob Lantz, on behalf of the Mininet Contributors