Best Guide to Understand the Importance of What Is Subnetting

With the advancement of technology and to meet the demand for the increase in IP addresses in the IT industry as well as to satisfy the personal requirement. To overcome this situation of assigning IP addresses to each device in a network, the concept of subnetting was introduced. 

The process of dividing IP addresses into smaller subunits that can later be assigned to multiple network devices in a network is referred to as subnetting. In this tutorial titled ‘what is subnetting?’, you will learn about various parts of subnetting in a comprehensive manner.

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What Is Subnetting?


The need for applying the concept of subnetting is to provide an alternate way to prevent the wastage of IP addresses. Then dividing an IP address into multiple smaller units that can work as a separate network unit known as subnet, in the host network is known as the subnetting process. Subnetting allows the network to avoid frequent traffic problems that occur in the channel, resulting in smooth transmission of information in the network.

The smaller network units, also known as subnets, can be individually configured according to the user's requirements. As you further go into the tutorial on ‘what is subnetting?’, you will see the need to use the subnetting process.

Why Apply Subnetting?


Every company requires an efficient way of designing their network channel for smooth and error-free data transmission over the network channel.

To overcome this problem of excessive use of network IDs, the concept of subnetting is applied in the system. To understand this, take a look at some of the reasons for using subnetting:

  • Sub-network: The most basic reason to apply subnetting is that it efficiently distributes an IP address into smaller subunits, according to the need of the network.
  • Increased Security: Subnetting makes it easier in establishing security units over the network channel to avoid data breaches.
  • Helps to prevent wastage of IP addresses.
  • Allows better communication between each subnetwork in the channel.

Next, in the ‘what is subnetting?’ tutorial, you will look into the work process of the subnetting concept.

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Working of Subnetting

The process of subnetting involves breaking down an IP address into smaller units that can be assigned to individual network units within the original network. This is done by using various techniques. 


Subnetting divides an IP address into two parts, namely network address and host address.

Then, using the subnet mask technique, you can further divide the divided address into units and assign them to various devices in a network. Taking the example of an IP address with /24 subnet mask can be divided into two sub-networks of /25.

In the next part of the tutorial ‘what is subnetting?’ you will understand the important characteristics of subnetting.

Characteristics of Subnetting

To design a subnetwork, some features are required to be understood properly which are:

  • Network ID: It is the first IP address in each Sub-Network in the main network ID. 
  • Broadcast ID: This feature represents the last IP address in each Sub-Network in the network ID. 
  • First Host ID: The next IP address after the Network ID is represented by the First Host ID.
  • Last Host ID: The IP address right before the Broadcast ID is represented as Last Host ID.
  • Next Network: This feature assigns the Network ID for the next sub-network. 
  • # IP Addresses: This feature represents the total number of IP addresses in the sub-network.

To better understand the above characteristics, you can refer to this example,


In this tutorial on what is subnetting?’ you looked into the need of applying subnetting and its working process in the network. Then in the next section, you will look into some drawbacks of applying concept subnetting.

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Drawbacks of Subnetting


Using subnetting to design your network channel does not always prove to be efficient; in some cases, it may affect the overall communication channel of the network, so you should always remember the below-mentioned points when applying subnetting in the network:

  • Complex Connections: With the increase in the no. of sub-networks, the complexity of the network also increases several-fold. This makes maintaining and troubleshooting the errors in the network.
  • Unused IP address: This problem arises as the sub-network is needed with sufficient IP addresses, but due to class addressing, many addresses remain unused.
  • Hardware Requirement: The communication between sub-network is efficient only with the involvement of proper hardware devices (router, switch, etc.), which are needed to share continuous data exchange.

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In this tutorial on ‘what is subnetting?’, you understood that through the subnetting concept, you could efficiently divide an IP address into smaller units, known as sub-networks. These sub-networks are interconnected through the subnet, which provides efficient network connectivity and increases the security level against cyber attacks.

To further understand this topic of subnetting, along with the other important network concepts, you can refer to Simplilearn’s Cyber Security Expert course. This will make you adept at using network concepts and their numerous applications in cyber security, hacking, and other related posts.

Do you have any questions related to this tutorial on ‘what is subnetting?’. If yes, feel free to mention them in the comments section at the bottom of this page. Our team will help you solve your queries ASAP.

About the Author

Kartik MenonKartik Menon

Kartik is an experienced content strategist and an accomplished technology marketing specialist passionate about designing engaging user experiences with integrated marketing and communication solutions.

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