Introduction to Intrusion Protection and Network Security
If your network (your connected computers) consists only of other computers in the same building you can still secure the network by securing the rooms the computers are in. An example of this would be two computers sharing the same files and printer, but not having a modem and not being connected to any other computers.
However, it's wise to learn about other ways to secure a network of connected computers, in case you add something later. Networks have a tendency to grow. If you have a network, an intruder who gains access to one computer has at least some access to all of them.
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