Why Network Segmentation Matters More Than Ever in Healthcare

Healthcare organisations are operating in increasingly complex IT environments.

Patient systems, clinical applications, medical devices, staff networks, guest Wi-Fi, cloud services and third-party platforms all need to work together. At the same time, many healthcare environments still rely on legacy systems that were never designed with today’s cyber threats in mind.

That creates a difficult balance: everything needs to be connected, but not everything should be able to communicate with everything else.

This is where network segmentation becomes critical.

The problem with a flat network

In a flat or poorly segmented network, an attacker who gains access to one device or account may have a relatively straightforward path to other systems.

A compromised workstation could potentially provide a route towards servers. A vulnerable medical device could become an entry point into a wider network. A compromised user account could provide access far beyond what that individual actually needs.

The initial compromise may be small.

The consequences can be much bigger.

This is why modern cybersecurity needs to focus not only on preventing attackers from getting in, but also on limiting what they can do if they succeed.

Segmentation limits lateral movement

Network segmentation creates boundaries between different parts of an IT environment.

Instead of treating the network as one large trusted environment, organisations can separate systems and users according to their role, risk and required access.

For example, a healthcare organisation might have separate controls around:

• Clinical systems
• Medical and IoT devices
• Corporate IT
• Guest and patient Wi-Fi
• Administrative systems
• Critical infrastructure
• Server environments
• Third-party or supplier access

The objective isn’t simply to create more network zones.

It is to control the communication between those zones.

If an attacker compromises a device on one segment, effective segmentation can make it considerably harder for them to move laterally into higher-value systems.

Healthcare has a particularly difficult segmentation challenge

Healthcare environments aren’t like conventional corporate networks.

There can be thousands of connected devices, multiple sites, clinical applications, specialist systems and equipment that needs continuous availability.

Some medical devices may be difficult or impossible to patch regularly. Others may run legacy operating systems or depend on specific network configurations.

At the same time, clinicians need fast and reliable access to the systems they rely on.

Security therefore cannot simply mean restricting everything.

Segmentation needs to support clinical operations, not get in the way of them.

That means understanding how systems actually communicate before making changes.

Patient Wi-Fi and clinical networks shouldn’t be treated the same

One common example is wireless access.

Patients and visitors may need internet access across hospitals, clinics and other healthcare facilities. Staff need access to corporate and clinical applications. Medical devices may require connectivity to specific systems.

Putting these different users and devices into the same network creates unnecessary risk.

Appropriate segmentation can help ensure that a patient using guest Wi-Fi cannot simply reach internal systems or connected devices.

The same principle applies to staff devices and clinical technology.

Access should be based on what is required, rather than what happens to be technically possible.

Medical devices are changing the attack surface

The growth of connected medical and IoT devices has made segmentation even more important.

Imaging systems, monitoring equipment, diagnostic devices and other connected technologies can all become part of the organisation’s digital attack surface.

The challenge is that traditional endpoint security controls aren’t always suitable for every device.

Network visibility and segmentation therefore provide another layer of protection.

By understanding which devices are communicating, where they are located and what they actually need to communicate with, security teams can identify unusual behaviour and restrict unnecessary pathways.

Segmentation also supports a stronger Zero Trust approach

Network segmentation shouldn’t be viewed as an isolated technology project.

It is increasingly part of a broader move towards Zero Trust principles.

Rather than assuming that something is trustworthy because it is already inside the network, organisations can continually consider:

Who or what is connecting?

What are they trying to access?

Does that access need to exist?

What should they be prevented from reaching?

This approach can be particularly valuable in healthcare, where users, devices, applications and third parties may all require different levels of access.

It can also strengthen resilience

Segmentation isn’t only about stopping cyber attacks.

It can also help organisations contain incidents and reduce their potential impact.

If one area of the network experiences a security incident, clearly defined boundaries can help prevent the problem from spreading across the entire environment.

That can be particularly important for healthcare organisations, where disruption to IT systems can have operational and clinical consequences.

The goal should be to ensure that one compromised device doesn’t automatically become an organisation-wide problem.

Segmentation needs to reflect the real environment

One of the biggest mistakes organisations can make is approaching segmentation as a purely technical exercise.

Creating VLANs or firewall rules doesn’t automatically create effective segmentation.

Before changes are made, organisations need to understand:

• What systems exist?
• Which devices communicate with each other?
• Which applications are business or clinically critical?
• Where are the legacy systems?
• What access do suppliers require?
• Which devices are unmanaged?
• Where could an attacker move if an endpoint were compromised?
• Which connections are genuinely necessary?

This is where network visibility, vulnerability assessment and traffic analysis become important.

You cannot effectively segment an environment that you don’t understand.

Where do you start?

For many healthcare organisations, the answer isn’t to redesign the entire network overnight.

A more practical approach is to identify the areas where segmentation can reduce the greatest risk.

Start by identifying your most critical systems and the routes that could potentially lead to them.

Then consider whether those pathways are necessary.

From there, organisations can look at firewall policies, access controls, network architecture, identity, wireless infrastructure and monitoring to establish stronger boundaries.

Segmentation should ultimately form part of a wider security strategy rather than being treated as a standalone project.

From compliance to practical security

With healthcare organisations facing increasing pressure around cybersecurity, resilience and frameworks such as the DSPT and Cyber Assessment Framework (CAF), segmentation can also form an important part of demonstrating that appropriate controls are in place.

But compliance shouldn’t be the only reason to review your network.

The more important question is:

If an attacker compromised one device in our environment today, how far could they get?

If the answer is unclear, it may be time to look more closely at your network architecture.

Security shouldn’t come at the expense of connectivity

Healthcare organisations need connected environments.

Clinicians need access to information. Devices need to communicate. Patients need connectivity. Staff need reliable systems.

The answer isn’t to disconnect everything.

It is to make connectivity deliberate.

Effective network segmentation helps organisations create boundaries around critical systems, reduce unnecessary access and limit the potential impact of a compromise, while still allowing the connectivity that healthcare environments depend on.

In an environment where one compromised device can potentially create a much larger security incident, knowing where your boundaries are matters more than ever.

Is your healthcare network segmented for the threats you face today?

ANSecurity helps healthcare organisations assess network architecture, identify security gaps and develop practical approaches to segmentation, infrastructure security and resilience.

If you’re unsure how far an attacker could move through your network following a compromise, it may be time to find out.