Zero Trust

Zero Trust is a security philosophy built on a single premise: no user, device, or service should be trusted by default, no matter where it sits relative to the network perimeter. Every request has to be authenticated, authorized, and continuously validated against identity, device posture, and context before it reaches an application or its data. Codified for many organizations by NIST’s Zero Trust Architecture (SP 800-207), it is the successor to the old “hard shell, soft center” perimeter model.

• Never trust, always verify - Trust is never inherited from network location; it is earned per request and re-checked continuously.
• Least-privilege access - Identities receive only the minimum access required, shrinking the damage any single breach can do.
• Assume breach - Systems are designed as if attackers are already inside, so segmentation and verification limit lateral movement.
• Identity and context at the center - Access decisions hinge on who and what is asking, on which device, under what conditions — not on an IP address.

In the API world, Zero Trust is the strategy and the Zero Trust Security Model and Zero Trust Network Access are how it gets implemented — through strong per-request authorization, OAuth 2.0 and OpenID Connect, sender-constrained tokens, and policy-driven access rather than trusted networks. As organizations discover that most of their real API usage is internal and between partners, the assumption of a safe private network collapses, and Zero Trust becomes the governing principle for how those APIs are secured. For the agentic turn, where autonomous agents and services call APIs constantly, treating every call as untrusted and verifying it against identity and policy is the only posture that scales.