Key Points:

• Network Segmentation involves dividing a network into smaller segments for security and reduces the attack surface.
• It helps enhance data security, aids compliance, and improves performance.
• Implementing Network Segmentation involves assessing your network, setting goals, choosing technology, creating segments, adding security, testing, educating employees, and regular reviews.

As the cost of a data breach continues to skyrocket, averaging $4.45M in 2023 , you might be looking for ways to secure your most sensitive data.

Network segmentation offers an extra layer of security for your business, that can isolate a data breach, and help you spot any anomalies from insider threats.

What is network segmentation?

Network segmentation involves dividing a computer network into smaller segments in order to improve security and reduce your attack surface.

Rather than one overall network working off its own rules, the smaller segments operate completely independently, with their own access controls and security policies in place. They could be divided based on the departments they cater for, or the sensitivity of data being transmitted.

Types of Network Segmentation

You can segment networks by a range of different methods, depending on what your needs are as a business:

1. Physical Segmentation

If you have critical systems that need to be isolated, physical segmentation could help you protect them. You can use different devices, such as routers, to do this.

2. Virtual Segmentation (or Logical Segmentation)

Rather than physically separating networks, logical segmentation relies on access controls and network policies instead. Using VLANs (Virtual Local Area Networks) to achieve this, logical segmentation can be easier to manage than physical.

3. Perimeter Based Segmentation

This focuses on the perimeter of the company network, separating the internal from the external. Traditionally, anything external was not trusted while anything internal was, but this is no longer the case. Even if you implement perimeter-based segmentation, you should also focus on your access controls internally to ensure sensitive data is protected as much as possible.

4. Role-Based Segmentation

Grouping users based on their roles within the organisation, you can approve or deny access to various network resources that are necessary/unnecessary for their job function. If someone from the Marketing department tried to access sensitive HR data, for instance, this could be denied and flagged.

5. Application Segmentation

With many different apps to manage, you may opt to place them in their own segments, to prevent any interference between apps, and secure any sensitive data held within.

Why does network segmentation matter?

Implementing network segmentation allows you to take a proactive approach against data breaches, putting you in control and minimising the risk of financial and reputational losses that could occur as a result.

Sheree Buller Lim, Head of Product at Metomic, says:

“Perhaps the biggest benefit of network segmentation is that it enhances your data security posture. With the network segmented, any potential threats can be contained within one network, preventing them from spreading to other parts of the network. This makes a hacker’s job a lot more difficult as their lateral movement is prohibited, and they are unable to keep harnessing data from different sources.”

Isolating networks also means that if you were to suffer a data breach, you could quickly react to the incident, knowing that your other networks wouldn’t be affected. With your attack surface reduced, the risk of sensitive data being exposed is minimised, as only authorised users will be able to access it.

If your business needs to comply with regulations such as PCI DSS, you might also be required to have network segmentation, or other security measures in place. By restricting access to sensitive data, you can ensure that you’re doing everything you can to keep sensitive data safe. For instance, if credit card information is isolated, a data breach in one network won’t necessarily reach your customers’ financial data.

As well as the benefit to your overall security, network segmentation can improve performance by reducing unnecessary traffic across your network.

What’s an example of network segmentation?

Businesses who operate a guest Wi-Fi network for their visitors have network segmentation in place. The guest network will work entirely separate from the internal network, limiting access for visitors and isolating the company’s internal resources.

This can prevent unauthorised access to sensitive data on the company network.

How to implement network segmentation for better security

There are a few steps you can take to implement network segmentation:

1. Assess your current network: Understand how your network is laid out and the devices that are connected to it. You should highlight where sensitive data lives, and what your potential security risks are.
2. Determine your goals with network segmentation: What do you want to achieve by segmenting your network? What data needs to be protected? What should you isolate, and what will people need access to?
3. Choose your technology: Decide how you’ll segment your network - whether it’s through VLANs, firewalls, or software-defined networking (SDN) solutions.
4. Create your segments: Now it’s time to start understanding the criteria for each segment, and what you’ll get out of it as a company. For example, creating a guest network will help keep visitors away from sensitive data. You should take access controls into consideration, as well as your policies for each network.
5. Set up your security: Will you use firewalls to enforce your policies? Will you encrypt your data? Choose the most appropriate security methods for your organisation.
6. Test your network: Is everything working as it should? Carry out penetration testing to identify any weaknesses in the system.
7. Educate your employees: Make sure your employees are aware of how the network segmentation will be working, and what they can do to access the information they need.
8. Regularly review your setup: Is it disrupting the flow of business or getting in the way of people doing their jobs? What can you improve?

How can Metomic help?

Metomic's data security tool adds another layer of security to your business, by minimising the amount of sensitive data you hold in your SaaS apps like Slack, Google Drive, and Microsoft Teams.

We focus on detecting and protecting sensitive data, without getting in the way of your employees doing their jobs.

To see how it works, try out our free Google Drive Risk Report and see where sensitive data is hiding in your company Drive.