IOS Emulation Just Got Better
Quite some time ago, I wrote an article on the Dynagen/Dynamips system that has been developed to emulate (not simulate) IOS routers using a PC. Back when I originally wrote this update, you could only emulate a 7200 router and it took quite a bit of tweaking & tuning text files to make it happen. Things have definitely changed
Kudos to InternetworkExpert for putting together a pre-built Dynagen/Dynamips lab that emulates 9 different 3640 routers connected together in an impressive topology. Sure, they've created this environment to map to their lab scenarios which is what their business is built on; however, they've been kind enough to allow anyone to download this pre-built IOS emulation package for free.
Update: Thanks MB for also adding GNS3 (http://www.gns3.net) to the Dynamips lineup. This is the best package for IOS emulation yet!
Yes, it may still take some reading of documents to figure out how to connect & setup, but most of the legwork has been done for you. With a little time, you can build a fairly massive Cisco lab environment with out spending a penny on lab gear. Here's the link for the download and documentation: