# Risk-Based and Adaptive Authentication
One-sentence definition: Dynamically adjust auth requirements based on context (IP reputation, device, geo, behavior).
## Key Facts
- Signals: impossible travel, new device, TOR/VPN, velocity, time-of-day.
- Outcomes: step-up to MFA, deny, or restrict session scope.
- Requires telemetry, baselines, and privacy-aware data handling.
- Beware bias; provide appeal/recovery paths.
- **Verify:** check official (ISC)² CBK and current exam outline.
## Exam Relevance
- Choose adaptive MFA to balance UX and security.
**Mnemonic:** “**Risk** drives the **ask**.”
## Mini Scenario
Q: Login from new country to admin portal—response?
A: Step-up to phishing-resistant MFA or block.
## Revision Checklist
- List 3 signals.
- Step-up vs deny.
- Data handling concern.
## Related
[[Single Sign-On (SSO) Patterns]] · [[Authentication Factors and MFA]] · [[Passwordless and FIDO2 WebAuthn]] · [[OpenID Connect (OIDC) and JWT]] · [[Access Reviews and Certification (IGA)]] · [[Domain 5 - Index]]