Dynamips simulates Cisco hardware on PCs. There are versions for Windows, Linux and MacOS. You need an IOS image from Cisco. The image will be started in the simulator and you get the feeling of using a real Cisco router. Ethernet, Frame Relay and ATM lines can be simulated. Do not expect the real bandwidth or perfomance from this lines. Dynamips helps you to do the logical testing of your network, it is not about performance. It turns your PC into a router, if you have 2 NICs.
Many candidates for CCNA, CCNP or CCIE use Dynampis to prepare for the exam.
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