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Tech riderRev. 29 Sept 2026

GNS3

Ch 057.2of 31 Network Testing Software
  1. 1Runs onLinux, Mac, self-hosted, Web, Windows
  2. 2CostsFree plan
  3. 3Simulation modelhybrid
  4. 4Real-time emulationYes
  5. 5Hardware-in-the-loopYes
  6. 6Deployment optionsdesktop
  7. 7Automation APIYes
7 lines stated Written from the maker's own pages: gns3.com, docs.gns3.com
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The GNS3 homepage

Overview

GNS3 is ranked #5 of 31 in network testing software on Specifiction. It runs on Linux, macOS, Self-hosted, Web, Windows. There is a free plan.

GNS3 plans and pricing

All plans
GNS3 Free Open source · no monthly or yearly license fees · device count limited by available CPU and memory docs.gns3.com · 29 Sept 2026

Compared on network testing software

Free plan
Yesgns3.com
Simulation model
hybridgns3.com
Real-time emulation
Yesgns3.com
Hardware-in-the-loop
Yesgns3.com
Deployment options
desktopgns3.com
Automation API
Yesgns3.com

Facts

Purpose
GNS3 lets network engineers emulate, configure, test, and troubleshoot virtual and real networks.docs.gns3.com · 29 Sept 2026
Open source
GNS3 is open source software that users can download and use for free.docs.gns3.com · 29 Sept 2026
Architecture
GNS3 consists of a graphical all-in-one client and a virtual machine, with local or remote server options.docs.gns3.com · 29 Sept 2026
Multi-vendor support
GNS3 supports devices and appliances from multiple network vendors, including Cisco, Brocade, Cumulus Linux, and HPE.docs.gns3.com · 29 Sept 2026
Emulation and simulation
GNS3 supports both emulated devices running actual images and simulated devices such as its built-in layer 2 switch.docs.gns3.com · 29 Sept 2026
Integrations
GNS3 supports Docker instances, QEMU-based appliances, hypervisors including VMware, VirtualBox and Hyper-V, and connections to real networks.docs.gns3.com · 29 Sept 2026
Appliance marketplace
The GNS3 Marketplace provides preconfigured appliance templates that use recommended settings and are tested by GNS3.docs.gns3.com · 29 Sept 2026
Cisco image requirement
Users must provide their own Cisco IOS images; GNS3 says it cannot provide them.docs.gns3.com · 29 Sept 2026
Security
GNS3 documentation says a GNS3 server has no authentication enabled by default and should be restricted at the network level.docs.gns3.com · 29 Sept 2026
Who it is for
GNS3 is used for networking education and certification practice, proof of concepts, demonstrations, and interoperability testing.docs.gns3.com · 29 Sept 2026
Scale limit
GNS3 does not limit the number of supported devices by license; the practical limit is the host computer’s CPU and memory.docs.gns3.com · 29 Sept 2026
Support
GNS3 points users to its documentation and community for help, questions, and bug reports.docs.gns3.com · 29 Sept 2026
Platform requirements
The documentation lists Windows, macOS, and Linux, and recommends the GNS3 VM for most Windows and macOS setups and complex topologies.docs.gns3.com · 29 Sept 2026

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Where it ranks on Specifiction

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