How to enforce Zero Trust across every resource

This post builds on the strategic foundations introduced in End VPN gaps with identity-first access. Read the strategic overview to understand why Zero Trust must apply to every resource before diving into implementation.

TL;DR: Your quick guide

• Reduce deployment risk by using report-only policies, emergency access exclusions, and phased rollouts.
• Use the guidance in How to enforce Zero Trust across every resource to simplify access security and move beyond VPN-based approaches.
• Begin with Microsoft Learn documentation for Conditional Access and Global Secure Access, including Microsoft Entra Internet Access and Microsoft Entra Private Access.

Best-practice steps to secure AI apps, on-premises apps, SaaS, and internet resources

Organizations rarely replace legacy access models all at once. Instead, they modernize in phases with policies that are disciplined, measurable, and easy to manage. Here are the recommended steps:

1. Inventory your access surface across AI apps, on-premises apps, SaaS, and internet destinations, then identify where policy coverage is inconsistent.
2. Assess and update Conditional Access policies to include user risk and session enforcement, keep user risk and sign-in risk in separate policies, and apply them by app sensitivity, user role, and device trust.
3. Start new policies in report-only mode, exclude emergency access accounts, and confirm licensing prerequisites such as Microsoft Entra ID P1, Microsoft Entra ID P2, or Microsoft Entra Suite where required.
4. Deploy Microsoft Entra Private Access with the appropriate private network connectors for hybrid and legacy applications, then enable Microsoft Entra Internet Access for web filtering, SaaS session control, and threat blocking.
5. Extend the same governance model to AI apps by reviewing authentication patterns, data access paths, plugin or connector exposure, and whether those apps are treated as sanctioned, unsanctioned, or high-risk resources.
6. Integrate monitoring and automation with Microsoft Sentinel and Microsoft Graph API for continuous improvement.

This phased model helps organizations avoid recreating old network assumptions inside a new platform. It also creates room to validate policy coverage, tune user experience, and retire VPN-heavy patterns without unnecessary disruption.

Best practices for Zero Trust infrastructure at scale

Technology alone does not deliver Zero Trust outcomes. Enterprises need an operating model that keeps policy manageable as coverage expands.

Several practices stand out:

• Treat Zero Trust as a cross-pillar strategy for identity, endpoints, apps, networks, infrastructure, data, and visibility, not as a standalone remote access feature.
• Use identity as the primary control plane instead of network location.
• Apply access rules at the app, user, and group level to keep policies precise and understandable.
• Verify explicitly with strong authentication and device-aware policies where appropriate.
• Use least privilege to limit access to only the apps, sessions, and resources users actually need.
• Define clear responses for elevated user risk, including session revocation where appropriate.
• Apply the same governance expectations to AI apps that you apply to SaaS and private apps, especially where they can access enterprise data or act on users’ behalf.
• Align private app access and internet traffic controls under one Zero Trust framework.
• Use automation and Microsoft risk detections to reduce manual response time.
• Roll out Conditional Access changes in report-only mode before enforcement.
• Exclude emergency access or break-glass accounts from broad access policies.
• Measure progress through both security outcomes and operational simplification.

Final takeaway

By combining Conditional Access with Global Secure Access, organizations can extend Zero Trust enforcement across every type of resource while reducing complexity and improving security outcomes.

Janice Ricketts

Janice Ricketts, MBA, BSEE, PMP | LinkedIn

Additional resources

• Zero Trust Implementation Guide
• Risk-based Conditional Access
• Operations Guide for Secure Access

Learn more about Microsoft Entra 

Prevent identity attacks, ensure least privilege access, unify access controls, and improve the experience for users with comprehensive identity and network access solutions across on-premises and clouds.

• Microsoft Entra News and Insights | Microsoft Security Blog
• Microsoft Entra blog | Tech Community
• Microsoft Entra documentation | Microsoft Learn
• Microsoft Entra discussions | Microsoft Community