Build and test networks with ease

GNS3 is a free software development program that allows you to create and test your own network in a risk-free environment. Currently maintained by Galaxy Technologies and the GNS3 community, this program is an open-source network software emulator that lets you combine virtual and real devices to simulate complex networks that suit your needs. It’s quite popular among many large companies and is also used as a teaching guide in preparation for network professional certification exams.

What is the use of GNS3?

First developed by Jeremy Grossmann, Dominik Ziajka, and Piotr Pękala, Graphical Network Simulator-3 or GNS3 lets you build, design, and test your networks in an easy manner—regardless of the scale or the hardware available. You don’t even need the latter as this software is a real-time network simulation for pre-deployment testing that can emulate the real behaviors of network hardware. This program and its extensive online documentation are user-friendly and can accommodate both new users and professionals.

With this software, you can create dynamic network maps for troubleshooting and such. You can also test over 20 different network vendors in risk-free virtual environments. With that said, however, it’s highly recommended that you also install virtual machines (VMs) before using this program to ensure optimal performance. There are five recommended VMs to try out: VirtualBox, VMware Workstation, VMware Fusion, VMware ESXi, and Microsoft Hyper-V. 

The main issue with this tool is that it requires multiple components to run—making it quite complicated to set up, even with the online tutorials to guide you. Regardless, it’s a highly customizable and versatile network tool that scales really well, letting you run hundreds of devices in a GNS3 topology. Plus, it offers remote access at any time and doesn’t even require an internet connection to verify a license.

An educational program

All in all, GNS3 is a great development tool to have on hand if your job involves networks or you’re currently studying them. Not only is this emulator free, but it’s easy to use and offers various features that other similar software don’t have. The only pressing drawback you’ll encounter is how complex its setup can be due to the other programs you have to install in order to ensure that it will run smoothly.