December 5, 2019, Subnetting is the process of dividing an existing network into smaller networks. These smaller networks are called subnets. Subnetting is used to free up more public networks as well as IPv4 segment addresses. This helps improve security and management. Understanding the basics of IPv4 Subnetting is important because it allows organizations to understand how to subnet and which subnetting class will best serve them.
A Brief Summary of IP Addresses & Binary
Understanding subnetting’s binary structure and decimal numbers of the IPaddress is essential in order to understand it. We will begin with the basics to help you understand subnetting. Here’s how an atypical IP address looks at 192.168.1.20.
IPv4 addresses can be 32-bit addresses. They are usually divided into four octets, or 8-bit numbers, separated by one decimal point. These four 8-bit numbers can range from 0 through 255.
Reasons Why Octets Can’t Go Beyond255
Because they are binary, the octets can only go up to255. This means that the largest possible IP address is 255.255.255.255. This IP addressin binary will look like: 11111111.11111111.11111111.11111111. It is important to note that there are 8 numbers between decimal points. Each number represents a bit, thus the 8-bit number grouping. Binary corresponds to the table below.
If we take the binary number 10000001, each 1 is turning on the number back to its original position. Thus, 1 in the first and last positions turns on 1 and 128.
Add all the positions together and you’ll get the decimal number:129 (128 + 1). The sum of all the positions is 255. This is how it works. These are the most commonoctets you will encounter in subnetting.