Zero Trust is a security concept based on the principle:
"Never trust, always verify."
Unlike traditional security models that automatically trust internal network traffic, Zero Trust assumes that every user, device, and application must be authenticated, authorized, and continuously monitored — regardless of whether they are inside or outside the network perimeter.
Verification over Trust
No one is trusted by default — every user, device, and service must prove who they are.
Least Privilege Access
Users and services only get the minimum access they truly need — nothing more.
Continuous Validation
Trust is not permanent — it’s reevaluated continuously (based on behavior, location, device status, etc.).
Micro-Segmentation
The network is divided into small, isolated zones to prevent lateral movement if an attacker breaks in.
Centralized Visibility & Logging
Every access attempt is logged and monitored — critical for audits, compliance, and detecting threats.
Multi-Factor Authentication (MFA)
Identity & Access Management (IAM)
Device Posture Checks (e.g., antivirus, patch status)
ZTNA (Zero Trust Network Access) as a VPN replacement
Micro-segmentation via cloud firewalls or SDN
Security Monitoring Tools (e.g., SIEM, UEBA)
Remote Work: Employees work from anywhere — not just inside a "trusted" office LAN.
Cloud & SaaS adoption: Data lives outside your data center.
Evolving Threat Landscape: Ransomware, insider threats, social engineering.
Without Zero Trust:
A user logs in via VPN and has full network access, just because they're "inside".
With Zero Trust:
The user must verify identity, device health is checked, and access is limited to only necessary apps — no blind trust.
Zero Trust is not a single product — it's a security strategy. Its goal is to reduce risk by enforcing continuous verification and minimizing access. When done right, it can drastically lower the chances of data breaches, insider threats, and lateral movement within a network.
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