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What is a Subnetwork?

What is a Subnetwork?

Have you ever wondered what a subnetwork is and how it operates? Subnetworks are integral to the modern internet, and without them, we would be in a very different place today. In this blog post, we’ll explore what a subnetwork is, how it functions, and why it’s so important. We will also discuss the different types of subnetworks and their applications in the modern world. By the end of this article, you will have a better understanding of networking fundamentals and what role subnetworks play in keeping our data secure.

What is a Subnetwork?

A subnetwork, or subnet, is a logical subdivision of an IP network. The practice of dividing a network into two or more networks is called subnetting. Computers that belong to a subnet are addressed with an IP address that includes the subnet mask.

Subnets are created by applying the concept ofaddress classes to TCP/IP internetworking. A classful network is one in which all hosts on the network share the same network prefix. Classful networking was the original method used to create IP networks. Today, however, most networks use classless addresses, meaning that each host can be assigned a unique network prefix.

When configuring a router for subnetting, you need to specify the number of bits that will be used for the subnet mask. For example, if you have a /24 network and you want to create two subnets, you would use a /26 mask. This would give you two networks with 64 hosts each:

Network 1:
Network 2:

You can also use wildcard masks to create more than two subnets from a single network prefix. Wildcard masks are explained in more detail in our article on CIDR notation .

How Subnetworks Work

Subnetworks are created by dividing a network into smaller groups, called subnets. Each subnet is a separate network with its own address space. Subnets are connected together using routers. Routers divide networks into subnets and route traffic between them.

When a network is divided into subnets, each subnet has its own unique address range. This allows devices on different subnets to communicate with each other without the need for a central router. Devices on the same subnet can communicate with each other without the need for a router.

Routers are used to connect devices on different subnets together. Routers forward packets of data between devices on different subnets. When a packet arrives at a router, the router looks at the destination address and determines which subnet the packet needs to be forwarded to. The router then forwards the packet to the appropriate device on that subnet.

Advantages of Using a Subnetwork

There are many advantages of using a subnetwork, including increased security, improved performance, and greater flexibility.

A subnetwork can be used to segment a network into smaller, more manageable parts. This can improve security by making it more difficult for unauthorized users to access sensitive data. It can also improve performance by reducing traffic congestion and increasing reliability. Additionally, a subnetwork can provide greater flexibility in terms of how users are able to access resources.

Disadvantages of Using a Subnetwork

When it comes to networking, there are multiple ways to segment a network into smaller pieces. One such method is called subnetting, which is the process of dividing a larger network into smaller subnetworks, or subnets. While subnetting can offer some advantages, it also has some disadvantages that should be considered before implementing it.

One disadvantage of using a subnetwork is that it can create more problems than it solves. In particular, if not done correctly, subnetting can lead to increased congestion and decreased performance. Additionally, setting up and managing a subnetwork can be complex and time-consuming. If not managed properly, a subnetwork can also become a security risk.

Another disadvantage of using a subnetwork is that it can limit the scalability of a network. As a network grows, adding new devices and users becomes more difficult with a subnetwork in place. Additionally, if the original purpose of the subnetwork no longer applies (for example, if the company changes locations), then the entire system may need to be reconfigured, which can be costly and time-consuming.

How to Create a Subnetwork

Subnetting is the process of dividing a network into smaller subnets, each of which can communicate with each other as if they were a single network. By doing this, you can improve network performance and security while still maintaining a single IP address space.

To create a subnetwork, you’ll first need to determine the size of your network and the number of subnets you’ll need. Once you have that information, you can use a subnet calculator to determine the proper IP addresses and subnet masks for your new subnets. Finally, you’ll need to configure your router or switch to route traffic between your new subnets.

If you’re not sure how to do any of this, don’t worry! We’ve got plenty of resources to help you get started, including our step-by-step guide to creating a subnetwork.


Subnetworks are a great way to increase the efficiency, performance and manageability of your network. By dividing your network into smaller logical networks, you can keep track of traffic flow better and make sure that resources are allocated correctly. If you’re planning on setting up a subnetwork or have any questions about them, don’t hesitate to contact an IT professional who can help you get set up in no time.