IP version 4

The format of an IP Version 4 address is dotted decimal notation, comprosed of four octets making it 32-bit addressing, for example 131.107.2.1. The IP address class is taken by looking at the number on the left-hand side. The last digit on the right-hand side cannot be a zero as it is the network ID, and cannot end in a 255 as this is the broadcast ID.

The Network ID is like a zip code; one person cannot have a zip code used by multiple people. The broadcast ID is used to send traffic to all hosts, therefor, we cannot use an IP address that ends in a zero or 255.

There are public addresses that you can lease and private addresses that are free, but can only be used internally. If you have a banger car, you can drive it around ...

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