Background and History - giangpham-cncs/Capstone GitHub Wiki

Graphical Network Simulator (aka GNS3) used to emulate the network with many configuration options and analysis tools from the vendors such as Cisco, Juniper, Arista, Huawei, etc.

Jeremy Grossmann is the original creator of GNS3. Jeremy comes from French, studied at a university in France for a Master's degree, and GNS3 is his final project at the university. The GNS3 idea comes up since he can't access Cisco routers and switches at all time (24/7) and he wants to create something on his laptop that he can work on it at any time and anywhere, something that really close to the real hardware. Jeremy has the first version called NS3, it is an academic network simulator, but it doesn't work well. Then, GNS3 was born with a graphical added to make it easier than NS3. GNS3 was created during his vacation at the island between Madagascar and Africa called Mayotte, a French territory. The first idea of GNS3 was created in 2006. A year later, the first version of GNS3 was released. Also in this year, another developer has developed a little application called VPCs that allows us to simulate the PCs that easy to connect to the GNS3 network.

For the long-term plan, Jeremy and his teams have a plan that removes the GNS3 GUI interface which the users install and use on their desktop. They will focus on web UI which users can open a browser and work on it. Web UI starts available on version 2.2 with read-only at the beginning.

GNS3 supports both emulated and simulated devices:

Emulation: GNS3 mimics or emulates the hardware of a device and you run actual images on the virtual device. For example, you could copy the Cisco IOS from a real, physical Cisco router and run that on a virtual, emulated Cisco router in GNS3.
Simulation: GNS3 simulates the features and functionality of a device such as a switch. You are not running actual operating systems (such as Cisco IOS), but rather, a simulated device developed by GNS3, like the built-in layer 2 switch.

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