Subnetting Examples
Subnetting is one of the most important and complex lessons of Networking. In this article, we will focus on How to Calculate Subnet Masks for various Subnetting Scenarios. We will focus on some Subnetting Examples.
Now, let’s start to our Subnetting Examples.
Subnetting Example 1
We have an IPv4 Prefix 220.220.220.0/24. How can we divide this IPv4 prefix into two different subnet?
To calculate the new subnets and subnet masks firstly we will determine our network bits and host bits. According to above example,
First 24 bits are network bits (First 3 Octets) : 220.220.220
Last 8 bits are host bits (Last Octet) : 0
Then, to calculate Subnet masks and new Subnets, we will determine how many bits will we need to borrow from the Host bits.
We need 2 Subnets and to have this we need x bits:
2⁰=1
2¹=2 (we need 2 Subnets, we borrow “1 bit”)
2²=4
2³=8
…
Our new subnet mask will be 24+1=25, /25.
The borrowed bit can be 0 and 1. So this two options will give you two new subnets.
Lest write only the last Octet in binary:
220.220.220.00000000 → 220.220.220.0/25
220.220.220.10000000 → 220.220.220.128/25
Subnetting Example 2
We have an IPv4 Prefix 50.50.50.0/24. How can we divide this IPv4 prefix into four different subnets for maximum 62 users?
To calculate our new subnet mask and subnets we will determine the bits that we need to borrow:
2⁰=1
2¹=2
2²=4 (we need 4 Subnets, we borrow “2 bits”)
2³=8
…
Our new subnet mask will be 24+2=26, /26.
The borrowed bit can be; 00, 01, 10, 11.
So this four option will give you four new subnets.
Lest write only the last Octet in binary:
50.50.50.00000000 → 50.50.50.0/26
50.50.50.01000000 → 50.50.50.64/26
50.50.50.10000000 → 50.50.50.128/26
50.50.50.11000000 → 50.50.50.192/26
To Continue to Learn Subnetting With More Examples Visit :
To view Subnetting Cheat Sheets, Visit :
https://ipcisco.com/lesson/ip-subnetting-and-subnetting-examples/
