Chapter 7
Networking basics
Updated July 3, 2026
Every machine on a network has an IP address. In IPv4 that is four numbers from 0 to 255 separated by dots: 192.168.1.10. The address alone does not say where the network ends and an individual host begins. A netmask does that, written after the address with a /: 192.168.1.10/24. The 24 means the first 24 bits out of 32 are the network address, and the remaining 8 bits are the host number inside it. This notation is called CIDR.
From the /24 you can read the boundaries at once: the network is 192.168.1.0, hosts run from .1 to .254, and .255 is reserved for broadcast. The smaller the number after the /, the larger the network.
Your own addresses co
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