You can create configurations and later deploy them to real routers.

You can use the Dynamips Emulator for training purposes and testing configurations. If, however, your emulated hardware doesn't have a VoIP FXS card, then you wouldn't be able to configure one in the Cisco IOS, even if the IOS supported it. However, because an emulator runs the IOS, you get every feature that the real IOS has (based on the limitations of the emulated hardware, of course).įor example, if your emulated hardware has a Gig Ethernet interface, and the IOS supports a Gig Ethernet interface on that platform, then you can use the Gig Ethernet interface. With a simulator, there are always missing commands and programming errors, and it can never really be as complete as the real IOS.

What's the difference? A simulator attempts to re-create the Cisco IOS using a programming language, but an emulator takes the real IOS router code, which you supply, and emulates the hardware behind it so you can run the real IOS on your PC. However, while simulators are useful, there's something even better that you can get for free - an emulator. A few months ago, I wrote ' Eight ways to strengthen your Cisco networking skills,' and the second suggestion I listed for improving your abilities was to use a simulator.