Open Source Network Simulators

The Common Open Research Emulator (CORE) is a tool for emulating networks on one or more machines. You can connect these emulated networks to live networks. CORE consists of a GUI for drawing topologies of lightweight virtual machines, and Python modules for scripting network emulation.

D.N.S. - aka Debian Network Simulator - is a Virtual Machine prepared to run as a guest in VirtualBox to emulate complex networks. It is based on Debian Jessie and is built around the well known GNS3 Project. Thanks to D.N.S. you can emulate Cisco and Juniper devices, as well as different kind of servers, to build complex networks for testing purposes or to have an huge help to study for a certifications like CCNA, CCNP, JNCIA and so on. The goal of the project is to provide an easy to use environment to build a virtual laboratory with GNS3 even without be familiar with GNU/Linux and configurations. So, if you are studying for a certification and/or if you want to build your own laboratory to simulate Cisco, Juniper devices and - in general - complex network topologies, you will find in D.N.S. a good friend :D The first public release has been published on Sunday, 9th of February 2014. Please, read the WiKi for details.

Graphical Network Simulator-3 is a network software emulator first released in 2008. It allows the combination of virtual and real devices, used to simulate complex networks. It uses Dynamips emulation software to simulate Cisco IOS.

Liowsn (Linux for works with WSN) was created to assist teachers, students and people involved with projects of Wireless Sensor Network (WSN). The operating system is Ubuntu 9.10 remastered and it contains several tools for simulation and testing installed to work with WSN. Discussion Group: http://groups.google.com/group/liowsn-users User manual: https://dl.dropbox.com/u/4912938/LiowsnManual_EN.pdf (English Version) https://dl.dropbox.com/u/4912938/LiowsnManual_PT.pdf (Portuguese Version)