Network segmentation is the process of dividing a network into smaller parts for various reasons—control, security, and boosting performance. It is also referred to as “network segregation,” “network partitioning,” and “network isolation.” Each part of a segmented network is called a “subnetwork” or “subnet.”

So when you’re asked “What is network segmentation?”, think of a subnet as a room in your house. You divide your living area into different spaces to designate areas for rest, recreation, and work. Without the partitions, you may end up eating anywhere, thus inviting pests if you don’t have that much time to clean daily.

Other interesting terms…

Read More about “Network Segmentation”

Network segmentation, like any architectural approach, has various use cases and benefits. But first, you may want to watch this video for a better idea of how it works:

Network Segmentation Use Cases

Organizations can segment their networks to do the following:

Create a Wireless Guest Network

A guest network limits the risk of confidential corporate information falling into the hands of malicious guests or even contractors. Network segmentation lets a company offer Wi-Fi service that provides Internet but not network access to visitors and contractors. And so anyone who logs in to its network with guest credentials gets an Internet connection but not the organization’s files or communication system.

Limit User Access

Insider threats are real. They can take the form of unhappy employees or spies. One way companies protect their secrets from these is by giving each department its own subnet. Within that subnet, group members have different access levels. Only those in the highest positions typically get administrator privilege. And any time an unauthorized user tries to access files he or she isn’t allowed to, an alert is triggered, and an investigation ensues.

Enforce Public Cloud Security

While cloud service providers are typically responsible for securing a customer’s cloud infrastructure, the client needs to protect its operating systems (OSs), platforms, access, data, intellectual property, source code, and content on the infrastructure. Network segmentation can play an essential part in isolating applications in cloud environments.

Ensure Regulatory Compliance

Some organizations, depending on their industry, are required to adhere to strict regulations, including the Payment Card Industry Data Security Standard (PCI DSS) for those that keep customers’ credit card numbers. Network segmentation can isolate all credit card information within a strict security zone and create rules letting only authorized users to access the area.

Network Segmentation Benefits

While network segmentation may come with certain costs, experts say its benefits outweigh the challenges. Some of these are:

Slow Down Attackers

No organization is immune to attacks, cyber or otherwise. A total of 1,001 data breaches exposing almost 165 million records in the U.S. alone were recorded in 2020. But network segmentation can buy companies extra time during an attack. Attackers that successfully breach a segmented target network will need additional time to break out of a segmented portion to get to what they really want.

Reduce Damage from a Successful Attack

Since robust network segmentation can keep attackers from breaking out of a subnet before an organization contains the breach, their access is also cut. As such, the damage caused by the breach is limited.

Improve Data Security

Network segmentation makes it easier for organizations to protect their most sensitive data. They can limit access to this to a handful of people within the organization. Should data loss occur, identifying the cause would be easier, too.

Make Least Privilege Policy Implementation Possible 

Companies that rely on restricting user access for protection typically have robust network segmentation. So even if a user’s access credentials get compromised or abused, it’s easier to track down who the responsible party is—insider or outsider.


As you’ve seen, the answer to the question “What is network segmentation?” is quite simple. It’s a means to manage, protect, and boost the effectiveness of groups of systems within a network.