Computers on a network communicate with each other using a special numbered addressing system. This is known as Internet Protocol (or IP). Each computer has a unique IP Address, which is four sets of numbers from 0-255, separated by a decimal point. This gives a total possible address space from 0.0.0.0 to 255.255.255.255. For example: 203.152.23.202 is an Internet IP Address.
IP addresses can be grouped into smaller logical segments of the entire address space, which can then be assigned to computers in a LAN. Breaking up IP Address space into smaller sub-networks is known as Subnetting.
This allows for logical control of data between LANs, and maps well onto the physical network design outlined.
