General Security Concepts

Assume breach and continuously validate every access attempt, regardless of origin or prior validation. — Zero Trust follows 'never trust, always verify.' No user, device, or application is trusted by default, even inside the network. Each access request must be explicitly authenticated and authorized based on current context, which is a major shift from perimeter-centric security.

Use a single hardened network perimeter as the primary defense against external intrusion. — A single hardened perimeter is the traditional approach Zero Trust moves away from. Zero Trust assumes the perimeter can be breached and relies on continuous verification and granular access controls instead of trusting internal traffic.

Grant broad, standing access to internal devices and services after initial authentication. — Zero Trust grants only the access needed for a specific task and time, then re-evaluates trust continuously. Broad, persistent access increases risk and conflicts with explicit verification and least privilege.

Isolate critical functions on a physically separate, air-gapped network segment. — Air-gapping can isolate systems, but Zero Trust is about securing access and interactions through continuous verification, not requiring physical separation. Most 5G functions need ongoing connectivity, so air-gapping is not the foundational principle tested here.