Marionnet is a virtual network laboratory: it allows users to define, configure and run complex computer networks without any need for physical setup. Only a single, possibly even non-networked Linux host machine is required to simulate a whole Ethernet network complete with computers, routers, hubs, switches, cables, and more Support is also provided for integrating the virtual network with the physical host network.

Marionnet was born in April 2005 as a simple textual interface to Netkit, written in OCaml by Jean-Vincent Loddo at the Paris 13 University for his own networking course.

The code has since been completely rewritten and redesigned in September 2005, in order to remove the dependency from Netkit and to ease the construction of a graphical interface, partly built on DOT. The architecture was further extended and the system made more general when Luca Saiu joined the project in 2007, contributing in particular to the dynamic reconfiguration aspects.

The system is now in active use in several universities in Metropolitan France and other countries.

Marionnet has reached a fairly stable state and is being successfully used for teaching networks in several universities around the world. The current development is centered around making the system easier to use for the average end user, with a particular emphasis on documentation. Internationalization is on the way (mostly in the marionnet_i18n branch) through GNU Gettext.

So far Marionnet has been presented at two international Computer Science conferences, many French events and at FOSDEM.

On top of a Linux host, the emulation of guest machines is achieved through User Mode Linux technology that allows to run many Linux kernels in user space as regular processes.

VDE - Virtual Distributed Ethernet project is responsible of linking together Uml machines in a virtual network, its purpose is to emulate cable, hub and switch devices allowing also to introduce perturbations in the communication.