Modern application environments are dynamic, distributed, and moving faster than ever. DevOps teams deploy new services daily, APIs multiply across regions, and traffic fluctuates by the hour. At the same time, organizations must uphold security, compliance, and availability without slowing innovation.
However, many security solutions are not architected to meet this level of complexity and speed. They treat security as a centralized checkpoint, creating visibility, enforcement, and scale bottlenecks.
Elastic WAF is designed around a powerful concept: separating the Control Plane and Data Plane. This approach, long embraced by networking, cloud, and service mesh technologies, gives organizations the flexibility to scale, govern, and protect without compromise. This blog will explain why this separation matters and how Elastic WAF applies it to transform application security.
Why Does it Matter?
Availability During Control Plane Disruptions
When the control plane (where configurations and policies are managed) experiences downtime, traditional security models may halt enforcement or introduce blind spots.
In contrast, architectures that decouple the data plane (where traffic is inspected) allow it to continue operating using the last known good configuration. AWS has emphasized that resilience during control plane failures is a key architectural principle in modern distributed systems.
Why it matters: Security enforcement continues even if the central management layer is down.
Performance Optimization
Control planes are typically optimized for orchestration and complex configuration logic. Data planes, however, are designed for speed, processing large volumes of traffic with minimal latency.
By separating these functions, organizations can enforce security policies in real time at the edge or within Kubernetes clusters while retaining the ability to define and monitor those policies centrally.
Why it matters: Security enforcement stays fast and efficient. Elastic WAF adds less than 10ms* of latency per request.
* Performance may vary based on environment and configuration
Independent Scalability
Applications don’t grow linearly. Traffic might spike suddenly, while the number of services or APIs grows gradually. With a decoupled architecture, you can scale the data plane based on traffic load and the control plane based on policy complexity or environment size.
This is standard in Software-Defined Networking (SDN) and Kubernetes, where control-plane logic and data-plane processing are scaled independently.
Why it matters: You don’t over-provision to maintain protection.
Fault Isolation and Resilience
Decoupling also creates fault boundaries. An issue in the control plane does not bring down inspection capabilities in the data plane. Inspection continues uninterrupted, whether you’re running security updates or recovering from a control-plane incident.
Why it matters: Security coverage is not compromised during maintenance windows or outages.
Governance Without Bottlenecks
Organizations with multiple business units, teams, or deployment environments must define security policies centrally but allow them to be enforced locally. Decoupling enables exactly that.
Why it matters: Your security team sets the standards while DevOps teams deploy services at their own pace. This improves governance and agility and reduces the perception that security slows development.
How Elastic WAF Separates Control and Enforcement
Elastic WAF divides its operations into the Control Plane and the Data Plane. This design gives teams centralized control while maintaining local performance and deployment flexibility.
The Control Plane resides in the Imperva Security Console. It is where security teams define policies, create domain-specific protections (Local Sites), and monitor events across environments. Each group of protected WAF instances is organized into a Controller Package, which acts as a configuration hub that distributes policies to the Data Plane.
The Data Plane consists of the Elastic WAF instances running in your environment, typically as pods within Kubernetes clusters. These instances receive policies from the associated Controller Package, inspect HTTP traffic in real time, and act based on defined rules. All security events and logs are returned to the Control Plane for visibility and analysis.
This architecture offers several key benefits:
- Centralized policy definition and unified visibility.
- Local traffic inspection that ensures minimal latency and data control.
- Scalable protection that adapts to development, staging, and production environments independently.
- Maintains security availability during management downtime
For example, you can define more permissive policies for a dev.myapp.com Local Site, while applying stricter security to www.myapp.com, all from a single interface. If traffic does not match any specific Local Site, it is handled by a Default Site policy, ensuring no requests go unattended.
Whether scaling across multiple cloud environments, segmenting security by environment, or managing many microservices, Elastic WAF’s Control and Data Plane architecture gives you the clarity, control, and confidence to move fast while staying protected.
About Imperva Elastic WAF
Imperva Elastic WAF brings our industry-leading Web Application Firewall directly into your deployment environment, containerized, lightweight, and ready to run wherever your apps live. From Kubernetes clusters to hybrid infrastructure, Elastic WAF integrates natively, delivering enterprise-grade protection without slowing innovation.
Built for agility, Elastic WAF empowers DevOps teams with frictionless security that deploys in minutes and protects applications instantly. Developers gain the autonomy to move fast, while CISOs retain centralized governance and visibility through the Imperva Security Console.
Elastic WAF is CDN-agnostic, cloud-agnostic, and architecture-agnostic by design. It reduces operational complexity while strengthening your security posture across all environments. Whether you are securing applications behind a third-party CDN, operating under strict compliance requirements, or scaling across global Kubernetes clusters, Elastic WAF is the future-ready solution that fits your architecture, not the other way around.
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