Dynamips, an IOS emulator which allows users to run IOS binary images from Cisco Systems.To allow complete simulations, GNS3 is strongly linked with :
GNS3 is a graphical network simulator that allows you to design complex network topologies and to launch simulations on them. With this IOS image you can run different Switching labs in GNS3. You can download 3640 Switch IOS image for Gns3.
