Our Takeaways from the Gartner® 6 Principles of Successful Network Segmentation Report

Talk to today’s security experts, and there’s one theme you’re likely to hear: segmentation is critical.

As a leading microsegmentation vendor, Illumio understands the challenges organizations face when trying to implement effective network segmentation.

The new Gartner® report, 6 Principles of Successful Network Segmentation, takes the complexity of segmentation projects and distills it into a practical framework.  

Teams can use Gartner insights to build successful segmentation projects. Let’s dig into each of their recommendations.

1. Start small and build network segments incrementally

The first Gartner principle is simple but powerful: start small. Segmentation projects that start too big often collapse under their own weight.

The key is to begin with small, high-impact use cases, such as critical applications, sensitive data, or compliance-driven zones, and then expand over time. This creates quick wins, builds confidence, and delivers measurable outcomes leaders can take back to their boards.  

At Illumio, we’ve seen customers thrive by starting small and letting segmentation mature as part of an iterative journey. This method allows security teams to continuously improve and adapt to the organization's evolving security needs.

2. Build governance for accountability

Segmentation doesn’t happen in a vacuum. It touches security, networking, operations, compliance, and the business. Without clear ownership, projects drift.

As Gartner explains, “One of the key functions of governance is to define acceptable risk and manage accountability.”

Illumio easily integrates with existing governance frameworks. This ensures everyone is aligned and accountable for their role in maintaining network security. In practice, governance turns segmentation from a one-off project into an organizational discipline.

3. Separate zoning design from implementation

According to Gartner, many segmentation projects get stalled because the selected technology either cannot deliver at scale or isn’t available in all the required environments. Establishing segmentation policies, which exist independently of the specific tools required to enforce or implement them, fosters portability across environments.  

A design-first approach gives you flexibility, and this makes it easier to adapt across data centers, clouds, and evolving infrastructures. Illumio is tool-agnostic, which allows for flexible, scalable zoning strategies that teams can adapt to any infrastructure.

4. Automate enforcement of segmentation

Segmentation done manually is segmentation done inconsistently. In the report, Gartner recommends redirecting the focus away from creating more zones and toward more automated deployment. The selected technology must fully integrate with — or at least not be in the way of — your cloud automation efforts.

Automated enforcement ensures policies are applied accurately, consistently, and at speed. It reduces human error, frees up valuable staff time, and strengthens resilience against fast-moving threats.  

Illumio makes it easy to automate segmentation so that controls get applied accurately and efficiently. We believe this helps reduce the risk of human error and improves your security posture. In our opinion, automation is the only way segmentation can keep pace with today’s dynamic environments.

5. Include segmentation in your global security design

Gartner explains that most network segmentation designs are entirely built as siloed projects that are disconnected from other infrastructure. Instead, segmentation should be woven into your broader security architecture.

That means connecting it with monitoring tools, incident response workflows, and compliance frameworks. By embedding segmentation into your global design, you turn it into a force multiplier for your entire security strategy.

With Illumio, you get comprehensive visibility and control. This makes it easier to integrate segmentation into the rest of your security strategy and design.

6. Unify policy management

The final principle tackles policy sprawl, one of the biggest pain points for security teams during segmentation projects.

Hybrid and multi-cloud environments can quickly create silos, with different tools managing different policies. Security leaders need to be wary of selecting segmentation technology without considering how it will integrate into a policy-change workflow for inbound, outbound, internal and inter-site traffic patterns.

With one place to define, enforce, and update policies, organizations reduce complexity and gain confidence that their security posture is consistent across the enterprise.

Choose segmentation platforms like Illumio to get centralized policy management. This simplifies administering segmentation policies and leads to consistent, scalable security.

Why these segmentation principles matter now

Our philosophy lies in delivering robust, flexible, and automated microsegmentation solutions.  

The six Gartner principles offer a roadmap for turning your segmentation project from a “someday” initiative into a core pillar of your cyber resilience.

Don’t wait for the perfect moment to get started. Start small, start smart, and let segmentation scale with your business. Your future resilience depends on it.

Download 6 Principles of Successful Network Segmentation to get more segmentation guidance from Gartner.

Gartner, 6 Principles of Successful Network Segmentation, Adam Hils, Andrew Lerner, 10 June 2025

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