What Is Zero Trust?
Zero Trust is a security architecture based on the principle of "Never trust, always verify." The traditional security model treats the internal network as trusted and focuses on external threats. Zero Trust, by contrast, trusts no one in advance — not the internal user, device, or application — and every access request is continuously verified.
This approach has become the new standard for enterprise security as hybrid work models have become widespread and the risk of insider threats has grown.
Why Did the Traditional Model Fall Short?
In the classic "castle and moat" model:
- Everything that enters the internal network is considered trusted
- Establishing a VPN connection grants broad network access
- Lateral movement (spreading through the network) is easily accomplished
The majority of ransomware attacks stem from an attacker who has penetrated the internal network being able to reach every part of the organization. Zero Trust eliminates this freedom of movement.
Core Principles of Zero Trust
1. Verify Identity
Every user and device must have its identity verified when making an access request:
- Multi-factor authentication (MFA)
- Device health check (patch status, EDR presence)
- Location and behavioral analysis
2. Least Privilege
Users can only access the resource they need, for only as long as they need it. Application-specific access instead of broad network access.
3. Assume Breach
The system is designed with the assumption that it has already been compromised. Microsegmentation is applied to prevent lateral movement; every activity is logged.
Zero Trust Components
Identity and Access Management (IAM) Identity providers such as Azure Active Directory and Okta; MFA and conditional access policies.
Device Trust Verifies that the device making an access request complies with corporate policy (MDM/UEM integration).
Microsegmentation Granular segmentation at the network and application layers; if one segment is compromised, others are not affected.
ZTNA (Zero Trust Network Access) Replaces traditional VPN. The user is given access only to authorized applications, not to the network. Fortinet ZTNA and Zscaler Private Access are leading solutions.
Continuous Monitoring Behavioral analysis at every session; session termination upon anomaly detection.
Zero Trust Maturity Model
Zero Trust is less a migration project and more a continuous maturity journey:
| Level | Characteristics |
|---|---|
| Initial | MFA implemented, basic segmentation in place |
| Advanced | Device trust, conditional access policies |
| Optimized | ZTNA, microsegmentation, automated response |
Where to Start?
A Zero Trust transformation does not require changing the entire infrastructure at once:
- MFA — The fastest and highest-impact starting point
- Privileged account controls — Restrict admin accounts
- Device inventory and compliance — Identify devices connecting to the network
- Application access segmentation — Transition from VPN to ZTNA
- Microsegmentation — Block lateral movement within the network
Conclusion
Zero Trust is the inevitable future of enterprise security when ransomware attacks, supply chain breaches, and insider threats are taken into account. While it may appear to be a large transformation project, it can be implemented step by step with the right prioritization. As NRC Sistem, we guide your organization through Zero Trust maturity assessment and phased implementation planning.