Understanding Intrusion Prevention Systems: What is an IPS?

An intrusion prevention system (IPS) is a critical layer of defense in containerized environments. Kubernetes enables faster releases and elastic scalability, but this agility introduces new complexity. As environments expand, so do the risks — attack surfaces widen, release cadences accelerate and operational teams face growing pressure.

Many organizations still rely on traditional perimeter defenses that lack visibility into internal cluster traffic, where many modern threats originate. As a result, misconfigurations, compromised containers and lateral movement between workloads can go undetected. IPS platforms proactively block these threats before they escalate by enforcing policies within the cluster and throughout the software lifecycle. 

What is an intrusion prevention system?

An intrusion prevention system monitors network traffic and immediately stops malicious activity. Instead of waiting for security teams to respond post-incident, an IPS applies enforcement to stop and report any unexpected behavior that may pose a threat — reducing damage and accelerating containment.

This capability proves especially important in dynamic environments like Kubernetes. Workloads spin up and down rapidly, and services often communicate across nodes or namespaces. An IPS observes these internal interactions and enforces security policies precisely where threats may arise.

Intrusion prevention system vs intrusion detection system

The main difference between an IPS and an IDS is action. While intrusion detection systems flag suspicious behavior, they don’t block it. In contrast, an IPS takes decisive action — dropping packets, terminating connections or triggering workflows that isolate affected services. In containerized architectures, where threats evolve quickly, proactive response makes a critical difference.

How does an IPS work?

In Kubernetes environments, service-to-service communication may remain internal and therefore escape notice. An intrusion prevention system addresses this blind spot and reinforces container security by inspecting traffic and enforcing policies directly on the data path.

Rather than relying on a single detection technique, most IPS platforms layer multiple approaches to identify threats more effectively. By combining complementary methods, they create a more adaptive and resilient defense. As a result, the platform should be able to effectively balance enforcement precision with performance, visibility and other priorities.

Signature-based

This method scans traffic for known indicators of compromise — such as exploit payloads, malware patterns or injection sequences. It’s effective against widely recognized threats and remains a foundational tool for blocking attacks that match Common Vulnerabilities and Exposures.

Policy-based

Policy-based IPS tools enforce security by blocking anything that falls outside of clearly defined, allowable behaviors. In Kubernetes environments, these tools often align with declarative security models. You can define policies as code, integrate them into Continuous Integration and Continuous Delivery pipelines, and apply them at admission, deployment and runtime. This approach supports granular controls like namespace isolation and pod-level whitelisting.

Anomaly-based

Anomaly-based IPS platforms learn what normal traffic looks like within a given environment. They build behavioral baselines over time, monitoring communication patterns to detect deviations — such as unauthorized lateral movements or previously unseen data flows. These tools excel at identifying and stopping zero-day attacks and subtle threats, which signature- or policy-based methods might miss. As applications evolve, anomaly detection evolves with them, ensuring protection keeps pace with innovation.

The four main types of intrusion prevention systems

Intrusion prevention systems come in several forms, each of which secures a different part of a modern environment — from the network layer to individual workloads and wireless entry points. 

Network intrusion prevention system (NIPS)

NIPS platforms observe and secure traffic flowing between services, nodes and clusters. In Kubernetes environments, they track east-west traffic inside the network and apply security policies that block suspicious communication paths.

Host intrusion prevention system (HIPS)

HIPS tools run on individual nodes or containers, and they monitor local activity such as system calls or file access. They are ideal for detecting and stopping privilege escalations, unauthorized modifications and the execution of unsanctioned software.

Network behavior analysis (NBA)

NBA tools track traffic patterns over time in order to detect unusual activity, such as unexpected protocol use or spikes in outbound data. NBA is useful for spotting stealthy or early-stage attacks that don’t match known signatures.

Why is an IPS system important for security?

In distributed systems, intrusion prevention systems provide an essential layer of protection that helps teams stay secure without losing momentum.

As organizations accelerate software delivery, traditional defenses often struggle to keep up. Each deployment can introduce new vulnerabilities or misconfigurations, and manual reviews or after-the-fact scans rarely catch problems quickly enough to prevent exposure. In addition, most modern enterprises manage a mix of Kubernetes environments. This variety can increase the risk of blind spots and makes it harder to apply consistent security controls.

An IPS in cybersecurity helps bridge these gaps. When built for Kubernetes, an IPS watches traffic between services, recognizes abnormal behavior and automatically applies security rules.

What threats does an IPS system neutralize?

Intrusion prevention plays a central role in blocking threats that exploit fast-moving, distributed applications. As organizations scale microservices across clusters and clouds, the attack surface grows — and so does the need for inline controls that detect and disrupt suspicious activity in real time.

Effective IPS platforms help neutralize a variety of threats.

• Lateral movement: Attackers who compromise a single service often attempt to spread across other services. IPS enforces internal segmentation, making it harder for malicious traffic to move freely within the environment.
• Exploit delivery: Payloads targeting known vulnerabilities in outdated services can bypass detection if traffic flows appear routine. Layer 7 inspection identifies these patterns, stopping exploits before they land.
• Data exfiltration: Unauthorized attempts to siphon data typically occur over seemingly legitimate channels. IPS tools can monitor and inspect outbound flows and also flag anomalies.
• Service misuse: Legitimate services can become entry points for unintended behavior, such as excessive API calls or rogue communication between containers. IPS policies can restrict connection frequency to prevent DOS attacks.
• Zero trust behavior: Unknown threats may not match known signatures. IPS tools that incorporate behavioral analytics can block out-of-policy behaviors or automatically isolate the affected workload.

Benefits of intrusion prevention systems

Legacy security tools can fall short in Kubernetes environments, where east-west traffic may bypass more conventional defenses. Intrusion prevention systems mitigate this risk by delivering in-cluster protection that scales with modern platforms.

Reduce alert fatigue

By combining signature-based, policy-based and anomaly-based detection, IPS platforms filter out noise and surface only meaningful deviations. This smarter detection model reduces false positives and helps teams focus on real risk.

Automate compliance

Many IPS platforms support out-of-the-box compliance checks for standards like CIS Benchmarks, NIST and PCI-DSS. These controls can generate evidence throughout the pipeline and at runtime, simplifying audits and reducing the need for manual tracking.

Close runtime blind spots

Container runtime security depends on real-time visibility into internal traffic and service behavior. Agentless approaches like SUSE Security can apply policy directly within the cluster to secure live workloads, enforce segmentation and detect lateral movement or anomalies that static tools often miss.

For many enterprises, especially those focused on securing Linux servers in hybrid or multi-cloud environments, IPS provides necessary policy enforcement and runtime visibility without added complexity. It enforces policies directly on internal traffic, automates evidence collection and keeps delivery pipelines moving — all without slowing forward progress.

Recently, IDC Frontier integrated IPS into its Kubernetes infrastructure to enforce runtime controls and accelerate secure deployments. As a result, the company cut its time-to-market for new services by more than 50%.

How to choose an intrusion prevention system

Selecting an intrusion prevention system for Kubernetes requires a focus on integration, adaptability and enforcement across the full software lifecycle. Teams need tools that align with modern delivery practices, support platform portability and reinforce enterprise security goals without introducing operational drag.

These five features deserve particular attention when you evaluate IPS tools:

Deep L7 visibility

Look for IPS platforms that actively inspect application-layer traffic — such as postgress, redis and gRPC. This level of analysis enables precise policy enforcement and exposes threats that often slip past basic network filters. With this insight, platform engineers can shape traffic rules intelligently, while security teams investigate alerts with full context.

Transparency and cloud native architecture

An open source IPS architecture enables full inspection, customization and long-term flexibility. Teams can review the inspection logic, submit change proposals and adapt the system as needed — maintaining control over protections and how they evolve.

CNCF compliance

Choose solutions that follow Kubernetes native patterns and integrate cleanly with the Cloud Native Computing Foundation ecosystem. Tools that support declarative configuration, Helm-based installs and cloud-agnostic deployments reduce complexity and accelerate rollout across diverse infrastructure.

CI/CD integration

An effective IPS extends protection into the development pipeline, by allowing security policies to be part of the deployment process. Enabling security-as-code can streamline release cycles and reduce costly security rework downstream.

Native compliance mappings

Framework alignment plays a key role in audit readiness. Seek IPS platforms that provide prebuilt controls for CIS Benchmarks, NIST 800-190 and PCI-DSS. When integrated as policy-as-code, these frameworks simplify governance and promote consistent enforcement across clusters.

Fitting an intrusion prevention system into your security infrastructure

A well-implemented intrusion prevention system should integrate cleanly into your existing security ecosystem — reinforcing controls without creating overlap or operational friction. In today’s cloud native environments, this means working across layers: from core clusters and CI/CD pipelines to edge sites and real-time monitoring systems.

Most organizations deploy IPS alongside:

• Perimeter firewalls, which govern ingress and egress traffic. IPS complements these by monitoring and enforcing policies on internal, east-west traffic.
• SIEM platforms, which aggregate and analyze security data. An IPS improves signal quality by contributing deep, contextual telemetry from runtime environments.  Teams can then correlate alerts more accurately and act more quickly.
• Edge security architectures, where consistent policy enforcement must span distributed and sometimes disconnected environments. IPS platforms that support lightweight, containerized deployment and zero trust segmentation help extend enterprise-grade protection to edge workloads.

Whether you are securing central platforms or edge nodes, IPS is most effective when woven into the fabric of your infrastructure. Organizations that align IPS strategy with orchestration goals often see significant improvements. Hyundai, for example, achieved a 99.95% SLA across its Kubernetes-based services by integrating SUSE’s container native IPS into its delivery and operations pipeline.

Using an intrusion prevention system with SUSE

Security doesn’t have to come at the cost of speed, scale or flexibility. SUSE Security empowers you to protect containerized environments without slowing innovation — enabling proactive, in-cluster enforcement and full lifecycle control from development through production.

Built on NeuVector and tightly integrated with SUSE Rancher Prime, SUSE’s IPS platform delivers deep packet-level visibility, real-time threat response and zero trust segmentation inside Kubernetes clusters. It unifies image scanning, Layer 7 runtime firewalling and behavioral analytics in a single container native stack. This convergence reduces tool sprawl while maintaining strong, adaptive protection.

SUSE also simplifies compliance by embedding security policies directly into pipelines and runtime environments. Prebuilt mappings automate evidence generation, easing audit prep and reducing manual oversight. Because the platform is fully open source, teams can review, customize and explain how the IPS enforces policies.

Whether operating on premises, in the cloud or at the edge, SUSE Security offers a scalable, transparent IPS solution that grows with your infrastructure and adapts to your delivery pace. 

Explore SUSE Security — strengthen defenses while enabling innovation.

Intrusion prevention system FAQs

How does an IPS differ from a firewall?

An IPS differs from a firewall because firewalls secure perimeter traffic. In contrast, IPS platforms monitor and act on internal, service-to-service communication that occurs inside clusters.

Who should use an intrusion prevention system?

Platform, security and compliance teams should use an intrusion prevention system. In organizations running production workloads across clusters, clouds or edge environments, these teams will greatly benefit from an IPS.

How can you integrate an IPS with existing security infrastructure?

To integrate an IPS with existing security tools, including your monitoring systems and runtime environments, you add it as part of your CI/CD pipelines. This integration enables the IPS to enforce policies automatically, avoiding the need for manual procedures.

What is the difference between Layer 4 and Layer 7 in an intrusion prevention system?

L4 sees ports and IPs, while L7 sees what the application is doing. Without L7, every encrypted connection looks the same. With L7, you can allow specific API calls and block everything else.