Mininet: Rapid Prototyping for Software Defined Networks

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

Mininet 2.2.0

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

New features in this release

This release provides a number of bug fixes as well as several new features, including:

• Improved OpenFlow 1.3 support

  • mn --switch ovs,protocols=openflow13 starts OVS in 1.3 mode
  • install.sh -w installs a 1.3-compatible Wireshark dissector using Loxigen
  • install.sh -y installs the Ryu 1.3-compatible controller

• A new nodelib.py node library, and new Node types including LinuxBridge, OVSBridge, LinuxRouter (see examples/) and NAT

• A --nat option which connects a Mininet network to your LAN using NAT (For this to work correctly, Mininet's --ipbase subnet should not overlap with any external or internet IP addresses you wish to use)

• An improved MiniEdit GUI (examples/miniedit.py) - thanks to Gregory Gee

• Support for multiple --custom arguments to mn

• Experimental cluster support - consult the documentation for details - as well as examples/cluster.py and an experimental --cluster option for topologies built with the default Host and OVSSwitch classes:

  mn --cluster localhost,server1,server2

Note that examples contain experimental features which might "graduate" into mainline Mininet in the future, but they should not be considered a stable part of the Mininet API!

A number of bugs have also been fixed, most notably multiple link support in Topo(). See github issues and the release notes on the Mininet wiki for additional information.

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.)

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

Mininet is an open source project and is currently hosted at https://github.com/mininet. You are encouraged to download the code, examine it, modify it, and 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

Best wishes, and we look forward to seeing what you can do with Mininet to change the networking world!

The Mininet Core Team:

• Bob Lantz
• Brian O'Connor
• Cody Burkard

Thanks again to all of the Mininet contributors, particularly Gregory Gee for his work on MiniEdit.