

The host portion is like the house and street number.Ī subnet defines the number of bits, out of 32, used for the “network portion” of the address. The network portion is like the city, state, and zip code. There are two parts to an IP address: The network portion and the host portion. The process of taking an extensive network and splitting into smaller networks is known as subnetting - and it’s freeing up more public IPv4 addresses. Luckily, the designers of IP addressing came up with a way to end this wasteful practice: Dividing networks using subnetting.
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How to define the network portion of a subnet IP addressĭuring the early stages of the internet, organizations assigned IP addresses like crazy until we nearly ran out. These are the most common octets you’ll encounter in subnetting: When all the positions are “turned on,” they add up to 255. 128Īdd up all the positions to get the decimal number: 128 + 1 = 129 So, 1 in the first and last positions “turn on” 128 and 1. Let’s use this binary number, for example: 10000001Įvery 1 in a binary number “turns on” the number in its position. Hence the term octet or the 8-bit number grouping. Note that there are eight numbers between the decimal points. The biggest IP address possible is 255.255.255.255

Why do octets only go up to 255? Because they’re binary. These octets range in number from zero to 255. To make addresses more straightforward, they are divided into four 8-bit numbers - or octets - separated by a decimal point. Here’s what an IP address looks like: 192.168.1.20Īn IPv4 address is a 32-bit number. To understand subnetting, you should first understand the decimal and binary structure of an IP address. Azure Identity & Access Management (IAM).Implementation – Best (Leading) Practices.WVD – Design & Implementation-Best Practices.
