This is likely a FAQ, but the official FAQ is noticeably sparring on the subject:
14.6 What simulation products are available ----------------------------------------------- 14.6.1 Q: Where can I find a good router simulator? A: "Never used one myself, but I think these are popular:
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Please comment on simulators you have used (or somehow else know about specifically).
Especially interesting would be cost/benefit, the 80% solution (can you do most everything you really need or want to do?), ability to simulate not just one router but entire networks.
Also, knowing of any free or very low costs simulators that worth ANY time and effort even if they not ideal...
What are the good and bad points about these simulators for teaching and learning:
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