# Attribute-Based Access Control (ABAC)
One-sentence definition: Decisions use attributes of subject, object, action, and environment evaluated by policy.
## Key Facts
- Flexible: time/device/location sensitivity, data classifications, risk score.
- Components: PEP (enforce), PDP (decide), PIP (provide attributes), PAP (manage policy).
- Supports fine-grained consent and least privilege at scale.
- Requires good attribute quality, lifecycle, and governance.
- **Verify:** check official (ISC)² CBK and current exam outline.
## Exam Relevance
- Pick ABAC where context matters (e.g., off-network deny write).
**Mnemonic:** “**A**ttributes **B**ecome **A**uthorization **C**laims.”
## Mini Scenario
Q: Allow doctors to view only their patient records during shift hours.
A: ABAC policy with role, patient relationship, and time attributes.
## Revision Checklist
- Name S, O, A, E attributes.
- PDP/PEP roles.
- Data quality concern.
## Related
[[Policy Languages and PDP PEP (XACML)]] · [[Access Control Models (DAC MAC RBAC ABAC PBAC)]] · [[Authorization in APIs (Scopes Claims Policy)]] · [[Identity Lifecycle (Joiner Mover Leaver)]] · [[Entitlement Management and SoD Conflicts]] · [[Domain 5 - Index]]