Zero Trust Architecture

Zero Trust is a security model based on the principle of "never trust, always verify." It assumes that threats exist both outside and inside the network, and no user, device, or connection should be implicitly trusted based on network location alone.

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The Problem with Perimeter-Based Trust

Traditional network security operates on a castle-and-moat model:

Traditional Model:

Outside (Untrusted) ──── [Firewall/Moat] ──── Inside (Trusted)

Problem: Once inside the moat, everything is trusted.
         An attacker who bypasses the perimeter has
         unrestricted access to internal resources.

This model fails because:

Assumption	Reality
The perimeter stops all threats	Phishing, insider threats, and supply chain attacks bypass the perimeter
Internal traffic is safe	Lateral movement is the primary technique for post-exploitation
VPN = trusted	Compromised VPN credentials grant broad network access
On-premises = secure	Cloud, remote work, and SaaS extend the network beyond any perimeter

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Zero Trust Principles