The Challenge We Faced

Picture this: Your security team is under pressure to strengthen defenses after a penetration test revealed gaps in your cloud infrastructure. Your compliance officer is asking questions about DDoS protection. Your CTO wants defense-in-depth. Sound familiar? This was exactly the scenario we encountered when working with a client preparing for their SOC 2 Type II audit.

Recently, we implemented Google Cloud Next-Generation Firewall (NGFW) in a multi-zone GCP environment for one of our client, and we want to share a practical overview of how the architecture came together and the key learnings from the deployment.

The goal was simple: Build defense-in-depth without overcomplicating routing or application design.

Architecture at a Glance

The solution combines multiple native GCP security layers working in harmony:

• CloudFlare – External DNS and initial traffic entry point
• Global External HTTP(S) Load Balancer – Public entry point 
• Cloud Armor – WAF + IDS/IPS at the edge
• Cloud NGFW Enterprise – Deep L7 inspection inside the VPC
• VPC Firewall Rules – L3/L4 network enforcement
• Zonal Backend VMs – Application hosting across multiple availability zones

This layered approach ensures threats are blocked as early as possible while still allowing deep inspection where needed. Each layer serves a distinct purpose, creating overlapping security controls that don’t duplicate effort.

Backend & Load Balancing Design

Infrastructure Setup:

• 4 VMs deployed across us-east1-b and us-east1-c
• Each VM runs Nginx + application with identical configuration
• Zonal Network Endpoint Groups (NEGs) used for each zone
• Global Load Balancer distributes traffic automatically based on health and availability

Design Decision: Because the backends are identical, routing rules were intentionally kept simple. No host-based or path-based routing was required. This reduced operational complexity and made troubleshooting significantly easier during the testing phase.

Security Layers in Action

Cloud Armor: Edge Protection

Attached directly to the Load Balancer backend service, Cloud Armor acts as your first line of defense:

• Configured with OWASP Top 10 WAF rules
• Geo-blocking rules for high-risk regions
• Rate limiting to prevent DDoS attacks
• Custom rules for application-specific threats

Real-World Impact: During penetration testing, Cloud Armor successfully blocked 100% of SQL injection attempts and XSS payloads before they ever reached the infrastructure.

Cloud NGFW Enterprise: Deep Inspection

Deployed with zonal inspection endpoints for high availability:

• Central firewall policy associated with the UAT VPC
• Security profiles enabled for intrusion detection and threat inspection
• Threat intelligence feeds automatically updated
• L7 inspection for encrypted traffic

Key Insight: Cloud Armor blocks threats early; NGFW inspects deeply. Together, they complement each other without creating redundant processing overhead.

VPC Firewall Rules: Network Segmentation

Traditional L3/L4 controls provide the foundation:

• Deny-by-default ingress rules
• Explicitly allow rules for required services
• Egress controls to prevent data exfiltration
• Service account-based access controls

Testing & Validation

We conducted comprehensive security testing:

Baseline Testing

• Simulated OWASP Top 10 attack scenarios
• Cloud Armor logs confirmed edge-level detection and blocking
• Malicious requests blocked at the edge

Deep Inspection Testing

• Advanced persistent threat (APT) simulations
• NGFW logs validated L7 inspection inside the VPC
• Detected encrypted malware in test payloads

Performance & Availability

• Load testing with legitimate traffic
• Zero impact on application performance
• Automatic failover between zones validated
• Legitimate traffic remained unaffected throughout all testing

Key Takeaways

1. Keep routing simple when services are identical – Don’t over-engineer your traffic distribution
2. Cloud Armor and NGFW solve different problems – They’re complementary, not redundant
3. Zonal NGFW endpoints align perfectly with multi-zone backends – High availability without complexity
4. Centralized VPC-level security policies scale better – Manage once, apply everywhere
5. Native GCP services integrate seamlessly – Minimal configuration, maximum protection

This setup reinforced an important principle: Strong security doesn’t have to mean complex architecture. When placed correctly, GCP’s native services work extremely well together.

Common Pitfalls and How to Avoid Them

• Cause #1: Incomplete security requirements documentation
  
  • Prevention: Complete a security questionnaire before architecture design

Performance Issues:

• Cause #2: Overly aggressive Cloud Armor rules
  
  • Prevention: Start permissive, then tighten based on legitimate traffic patterns
• Cause #3: NGFW inspection on unnecessary traffic
  
  • Prevention: Use selective inspection based on risk profile

Conclusion: Security That Scales With Your Business

At Prokopto, we work closely with growing Healthcare SaaS and cloud-native companies that need enterprise-grade security without enterprise-level complexity. Whether you’re preparing for a SOC 2 Type I, II audit, HIPAA, addressing findings from a penetration test, or proactively strengthening your cloud security posture, the challenge is always the same: how to do it right, without slowing the business down.

This GCP defense-in-depth architecture demonstrates that when native cloud services are designed thoughtfully, security becomes an enabler, not a bottleneck. By combining Cloud Armor, Google Cloud NGFW, and Global Load Balancing in the right places, our clients gain stronger protection, clearer audit evidence, and operational simplicity, all without re-architecting their applications.

That’s where Prokopto comes in.

We help teams design, validate, and operationalize cloud security and compliance programs that scale as they grow, from early-stage startups to audit-ready organizations. Our focus is simple: reduce risk, accelerate compliance, and give leadership confidence that security is handled the right way.

👉 If you’re unsure whether your current cloud architecture (GCP, AWS, Azure) will stand up to real-world threats or audit scrutiny, send us your design. We’ll pressure-test it, free of charge, under mutual NDA.

🚀 Ready to Strengthen Your GCP Security?

We’re happy to help with:

• Architecture reviews and defense-in-depth design
• SOC 2–aligned security implementations on GCP, AWS, Azure
• Cloud Armor & NGFW policy templates
• Cost-aware security optimization
• Advisory or end-to-end execution

📩 Email: info@prokopto.io

📅 Strategy Call: 30-minute security & compliance discussion

🔗 LinkedIn: Follow Prokopto for practical Cloud security & Compliance insights
https://www.linkedin.com/company/prokopto-inc

Or reach out directly:

• Email: info@prokopto.io
• LinkedIn: https://www.linkedin.com/in/narenravilla/

Comments & Discussion

Have you implemented similar security patterns in GCP? What challenges did you face? Share your experiences with us at info@prokopto.io, we’d love to learn from your journey too!