This case study outlines the design and delivery of an enterprise Zero Trust architecture to modernize secure access, reduce reliance on legacy VPN and proxy solutions, and enable secure business operations in a regulated environment.
Business Challenge
The organization relied on traditional perimeter-based access models that created:
Inconsistent access controls across users and applications
Increased attack surface due to network-level trust
Operational complexity supporting legacy VPN and proxy platforms
Limited visibility into user and application access patterns
At the same time, the business required:
Secure access for a distributed workforce
Minimal disruption to mission-critical applications
Alignment with regulatory and compliance requirements
Risk Context
Key risks identified included:
Over-privileged network access
Limited segmentation between users and applications
Increased exposure from legacy access technologies
Audit and compliance challenges due to inconsistent controls
Architecture Strategy
A Zero Trust architecture was selected to enforce identity- and context-based access controls.
Key architectural principles:
Never trust, always verify
Application-level access instead of network-level access
Centralized policy enforcement
Consistent controls across user locations and device types
Architecture Design
The architecture leveraged:
Zscaler Internet Access (ZIA) for secure internet and SaaS access
Zscaler Private Access (ZPA) for application-level private access
Identity-based access policies
Device posture and context-aware controls
Centralized logging and visibility
Traffic steering, SSL inspection strategy, and access policies were designed to support offices, data centers, and remote users while maintaining operational stability.
Implementation Approach
The solution was delivered using a phased approach:
Architecture definition and stakeholder alignment
Pilot rollout with controlled user groups
Progressive expansion with policy standardization
Migration of legacy VPN access to application-level segmentation
Ongoing optimization and operational tuning
Vendor engineering teams and internal application owners were engaged throughout the process to ensure alignment and resiliency.
Business Outcomes
The Zero Trust architecture delivered:
Reduced enterprise attack surface
Consistent access policies across the organization
Improved visibility into user and application access
Simplified access management and governance
Stronger alignment with regulatory and audit requirements
Secure enablement of distributed and hybrid work models
Key Takeaways
Zero Trust architecture significantly improves security posture when aligned with business workflows
Application-level access reduces risk compared to network-level trust
Phased delivery minimizes disruption in regulated environments
Collaboration with application and identity teams is critical for success