Zero Trust is a security model that eliminates the concept of a trusted network perimeter. Every user, device, and request is treated as untrusted by default. Access is granted only after verifying identity (MFA), device health (encryption, patches), and enforcing least privilege (minimum permissions needed). Microsegmentation operationalizes zero-trust by dividing a network into micro-zones (database zone, API zone, web zone, admin zone). Each zone has strict ingress/egress policies enforced by firewalls or policy engines. A compromised web server cannot access the database unless explicitly granted.