Implementing Zero Trust Security

1. Understanding Zero Trust Principles

Principle	Detail
Never trust	No implicit trust by network location
Always verify	Every request authenticated + authorized
Least privilege	Just-enough, just-in-time access
Assume breach	Limit blast radius
Frameworks	NIST SP 800-207, BeyondCorp (Google)

2. Implementing Continuous Authentication

Re-evaluate identity throughout session — not just at login. See section 50.

3. Using Context-Aware Access

Decisions consider device, location, risk. See section 51.

4. Implementing Device Trust

Signal	Detail
Hardware attestation	TPM, Secure Enclave, StrongBox
MDM enrollment	Managed device
Compliance	OS patch, encryption, EDR running
Certificate	Per-device client cert

5. Verifying Every Request

Layer	Check
Edge proxy	Authenticate, basic policy
Service	Fine-grained authorization
Data	Row-level security

6. Implementing Micro-Segmentation

Aspect	Detail
Network	Per-workload firewall rules
Identity-based	Service mesh policies, not IPs
Tools	Istio AuthorizationPolicy, Calico, Cilium

7. Using Least Privilege Access

Practice	Detail
JIT elevation	Time-bound role assumption
Scope-narrowed tokens	Per-operation scopes
Default deny	Explicit allow only

8. Implementing Strong Identity Verification

Method	Detail
Phishing-resistant MFA	FIDO2 / Passkeys mandatory
Workload identity	SPIFFE/SPIRE for services
Identity assurance	NIST 800-63-3 IAL/AAL/FAL levels

9. Monitoring and Logging All Access

Every decision logged for audit and ML training. See sections 53-54.

10. Implementing Adaptive Authentication

Risk-based decisions per request — same identity may get different access based on context. See section 49.