GNS3 – Graphical Network Simulator
“GNS3 is a graphical network simulator which provides you a real lab environment for learning and testing complex networks. With this tool you do not need to have dedicated network hardware devices. You can design and configure virtual networks on a traditional PC or a Raspberry Pi, and simulate in the closest possible way to how the real networks perform.
If you want to design and test your automation system network, GNS3 can just work fine for you. It allows you to run many virtual hosts with operating systems such as Linux, Windows, MacOS X or FreeBSD.”
GNS3 – Documentation and Download
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