Zero Trust

Overview

Zero Trust assumes no user, device, or network location is automatically trustworthy — access is continuously verified based on identity, device posture, location, and risk.

Key concepts

"Never trust, always verify"
Verify explicitly, least privilege, assume breach
Conditional access based on context

How it works

Zero Trust is a security model that does not automatically trust users, devices, applications, or network locations. Its core idea: never trust, always verify. A user isn't automatically trusted just for being on an internal network or using a company-owned device — access decisions weigh identity, permissions, device security, location, behavior, and how sensitive the requested resource is.

Core principles

Principle	What it means
Verify explicitly	Verify every user and device before granting access.
Least privilege	Give only the access needed for a specific task.
Assume breach	Assume a breach is possible and limit how far an attacker can move through the environment.
Continuous monitoring	Continuously monitor systems, devices, identities, and security events.
Reevaluate trust	Re-check trust when risk changes — e.g. a login from an unfamiliar location or device.

Putting Zero Trust into practice

Require MFA for important accounts and all remote access.
Use role-based access controls and remove unnecessary permissions.
Check device posture before granting access — patched, encrypted, protected by endpoint security.
Use conditional-access rules that weigh user, device, location, and risk level.
Segment networks so a compromised device can't easily reach sensitive servers.
Monitor for suspicious behavior — impossible travel, repeated failed logins, unusual downloads, privilege escalation.
Use separate standard and administrator accounts for system administration.

Worked example: the same user, two contexts

Scenario	Outcome
Managed, updated laptop, normal location	Access allowed after MFA.
Unfamiliar device, unusual country	Additional verification required, or access blocked entirely.