Security Model

Zero Trust Security

Zero Trust is the security architecture Signed-I/O is built on. It replaces the outdated assumption that anything inside a network perimeter is safe, and instead requires every access request to be verified — explicitly, continuously, and with least privilege.

The core idea

Traditional security models assumed that users and systems inside a corporate network could be trusted by default. Modern threats — insider attacks, compromised credentials, supply-chain breaches — have proven that assumption wrong. Zero Trust eliminates implicit trust entirely.

The guiding principle, coined by John Kindervag at Forrester Research in 2010 and later formalized by NIST and CISA, is simple: never trust, always verify. Every request — from a user, a device, or an internal service — must be authenticated, authorized, and continuously validated before access is granted.

The seven pillars

NIST Special Publication 800-207 defines Zero Trust around seven core tenets:

All resources are treated as untrusted

No asset — on-premises or cloud-hosted — is inherently trusted. Trust is never derived from network location.

All communication is secured

Every connection is encrypted and authenticated regardless of where it originates or terminates. There is no trusted internal network.

Access is granted per-session with least privilege

Each request grants only the minimum permissions required for that specific action. No standing access, no broad permissions persisting across sessions.

Access is determined by dynamic policy

Authorization decisions evaluate identity, device posture, behavioral signals, and context at the time of every request — not once at login.

Device integrity is monitored continuously

The health and compliance status of every device is assessed before and during access. Compromised or non-compliant devices are denied or restricted automatically.

Authentication and authorization are strictly enforced

Strong identity verification — including multi-factor authentication — is required before any access is granted, for every user and every service account.

All activity is collected and analyzed

A complete, tamper-evident log of every action is maintained. Anomalies are detected in real time, and audit records are available for investigation and compliance.

How Signed-I/O implements Zero Trust

Signed-I/O applies these principles at every layer of the platform:

Further reading

The following authoritative sources provide the standards and guidance that underpin Zero Trust architecture:

Questions about how Zero Trust is applied in your Signed-I/O environment? security@signed-io.com