Subnetting enables a much more efficient use of IP addresses compared to class licenses. It also enables you to separate a network for security (separating a bank of public access computers from your more private computers) and for bandwidth control (separating a heavily used LAN from one that’s not so heavily used).
Exam Tip
You need to know how to subnet to pass the CompTIA Network+ exam.
The cornerstone to subnetting lies in the subnet mask. You take an existing /8, /16, or /24 subnet and extend the subnet mask by adding more ones by taking away the corresponding number of zeroes. For example, let’s say you have an Internet ...

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