That pretty much has been obviated by switched hubs. I think this is a common homework question still but very outdated.
https://www.google.com/search?q=create+23+subnets+with+30+hosts.&ie=utf-8&oe=utf-8
So I am wondering if this is possible. I am trying to create 23 subnets with 30 hosts. What would be the subnet mask? How would I make this possible, I've completely confused myself.

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