Zero Trust Architecture: From Framework to Firewall Rules
The perimeter is dead. Not dying — dead. Every breach report from 2025 reinforces the same lesson: attackers are already inside. VPN credentials are phished in bulk, supply chain integrations create implicit trust paths, and cloud workloads span providers with no chokepoint to inspect. Yet most enterprises still allocate the majority of their security budget to perimeter controls that assume a clear inside and outside.
Zero Trust Architecture (ZTA) replaces that assumption with a simple principle: never trust, always verify. Every access request — regardless of source network, device posture, or previous authentication — must be evaluated against policy in real time. This post walks through the NIST 800-207 framework, maps each tenet to practical controls, and follows Apex Financial Group through an 18-month migration from castle-and-moat to zero trust.