The answers are in these questions you can research at google.com.
1. What is a MAC address?
2. Can we log activity on our network?
Some campus are open, so the access is free. The only downside is if you leave your machine too open and allow access to your stuff. Imagine if you didn't have a firewall and had your "C" drive shared. Just imagine another person pressing the delete key.
Bob
I can connect to the wieless network of my local univesity. I am sure they can tell that I am there but how would they know who I was? It seems like they might notice me among the 12000 or so students but how would they get my personal info? I am sure that microsot has an identifying code there somewhere but I don't understand how it would work. The thing is that my cable modem is as fast as the wireless connection.They do not encrypt the network. Why not I don't know.

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