Gartner® Competitive Landscape for Network Security Microsegmentation: Why We Believe It's a Foundational Zero Trust Control

Today’s cyberattacks don’t succeed because hackers get in. They succeed because no one stops them from spreading. That’s the issue Zero Trust is meant to solve — and one many security teams still struggle to address.

Containing breaches is getting harder by the day. Today’s networks move fast. Cloud growth, IT/OT overlap, and automation have changed how networks behave. Older security controls simply haven’t kept up. The result: once an attacker gets a foothold, they can move freely and turn a small breach into a major crisis.

In our opinion, Gartner’s latest research points to microsegmentation as a core way to address the security gap. It works by enforcing Zero Trust where it matters most: at the workload level.

In its new report, Competitive Landscape: Network Security Microsegmentation, “Gartner defines network security microsegmentation as an effort that can create more granular and dynamic access policies than traditional network segmentation (often north-south traffic segmentation).”  

Gartner adds that microsegmentation “allows the insertion of a security policy between any two workloads in the same broadcast domain — with microsegmentation technologies narrowing fine-grained network zones down to individual assets and applications.”  

This is Zero Trust in practice. Instead of letting systems talk freely, microsegmentation validates every connection. It limits access, adapts as environments change, and contains breaches before they spread. For security teams, it makes Zero Trust real.

Why cloud and hybrid environments are driving microsegmentation adoption

Modern networks never stand still. Workloads spin up and down in seconds. Apps stretch across clouds and data centers. APIs link systems that no one ever mapped.

As Gartner puts it, “microsegmentation is increasingly critical as organizations shift to hybrid, cloud, and containerized environments.”  

Static controls don't work in a world that moves this fast. They fall behind rapid changes, leaving gaps in enforcement and growing risk.

Then there’s visibility. The report notes that in today’s fast-moving clouds, “gaining real-time visibility into all assets, communications, and dependencies is difficult, making it challenging to create and maintain effective microsegmentation policies.”  

Zero Trust starts with seeing how systems talk to one another. You can’t control traffic you can’t see.

Scale only compounds the problem. Gartner notes that “as the number of microsegmentation rules grows, especially in largescale or multi-cloud environments, managing, auditing, and troubleshooting policies becomes increasingly complex.”  

That’s why security leaders want simpler ways to manage policy and enforce least-privilege access.  

How AI is shaping the future of Zero Trust enforcement

AI is one way to get there. It can help teams manage large amounts of data and make faster decisions.  

Gartner notes that “AI can improve visibility for organizations by analyzing metadata from multiple sources (network traffic, logs, identity stores).” It also explains that “AI can assist with more accurate, business-tailored segmentation decisions as organizations strive for granular segmentation based on application identity, user roles, and behavioral context.”  

Put another way, AI helps teams spot patterns and trends faster. That leads to smarter rules and tighter controls.  

But Gartner urges caution. The report warns that “there is a lack of trust and safety in AI-driven microsegmentation, requiring human oversight, transparency, and robust safeguards to prevent risks like model poisoning.”  

In other words, AI should guide security choices, not replace them. Human judgment still matters.

Gartner expects trust in these tools to grow over time. It predicts that “by 2030, 10% of organizations will have sufficient trust to run autonomous agents to segment their networks with no human oversight, up from less than 1% in 2026.”  

Even then, trust, governance, and transparency will remain central to Zero Trust.  

Why IT/OT convergence is expanding the role of microsegmentation

Containing breaches gets even harder when policy reaches into operational technology (OT).

That’s because the line between IT and OT systems is growing less clear. As they converge, security needs are growing more complex — and the stakes are rising.  

In OT, segmentation follows different models. Gartner explains that “‘microsegmentation’ generally refers to implementing segmentation at the zones and conduits level to ensure alignment with operational and safety requirements,” following standards like ISA/IEC 62443.  

In these cyber-physical systems (CPS), safety and uptime come first. That limits how teams can apply standard IT controls.

Gartner flags a gap: “it is important to note that the vendors profiled in this research primarily focus on IT microsegmentation and broadly lack the specialized capabilities offered by CPS protection platforms, particularly in areas such as vulnerability and threat management.”  

Teams want to apply consistent Zero Trust policies for IT and OT from one place — but without forcing both into the same security model.

As Gartner notes, “many organizations are seeking unified management of IT and CPS operations while supporting the implementation of distinct security controls tailored to the unique safety requirements of CPS environments.”  

Microsegmentation is becoming the enforcement layer for Zero Trust

Across all of these trends, one thing is clear: microsegmentation has become a core part of how Zero Trust is enforced. A Zero Trust strategy grounded in microsegmentation helps teams achieve the key outcomes that Gartner highlights, including “operational simplicity, automation, unified management, and strong compliance to remain competitive.”

Strategy alone doesn't stop breaches. Microsegmentation gives Zero Trust teeth.

Turning Zero Trust strategy into real-world enforcement

Zero Trust only works when it is applied everywhere. That means enforcing least-privilege access across clouds, data centers, endpoints, and OT systems. It also means updating rules in real time as things change.  

Modern microsegmentation does exactly that. It cuts off excess traffic, drops blind trust, and stops attacks before they spread.

Illumio was built with this goal in mind. The Illumio Platform shows teams how workloads communicate and builds walls that stop attacks from spreading. And it works across the cloud, data centers, and hybrid environments. That means security teams can apply Zero Trust without reworking their networks.

For leaders ready to move from planning to action, microsegmentation offers a clear path forward.  

Learn how Illumio can help you make Zero Trust enforceable — starting with microsegmentation.  

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