Understand the concept
An IPv4 address has 32 bits. A prefix such as /24 tells you how many leading bits represent the network. Subnet masks help determine which addresses belong to a subnet.
For 192.168.10.0/24, the usual network address is .0, broadcast .255, and usable host addresses are .1 through .254. In a /28, each subnet spans 16 addresses.
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Practice task
Practice finding block size and the containing network before choosing usable host ranges.
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