Authentication in Identity & Access Management
Authentication is the first step in IAM — verifying identity before granting access. A strong authentication strategy ensures only authorized users gain entry to your systems.
Types of Authentication
- Password-based: The traditional username/password model, now often enhanced with password policies and breach monitoring.
- Multi-Factor Authentication (MFA): Uses two or more factors — something you know (password), have (token/device), or are (biometrics).
- Passwordless: Eliminates passwords via biometrics, email links, or FIDO2 authenticators.
- Biometric: Fingerprint, facial recognition, and voice authentication methods, integrated for seamless user access.
- Adaptive Authentication: Dynamically adjusts authentication requirements based on risk signals like location, device, behavior.
How Authentication Works
A typical authentication flow looks like this:
- User initiates a login request
- System prompts for authentication (e.g., MFA)
- Credentials or biometric data are verified
- Upon success, a session or token is issued

Authentication Standards
NIST SP 800-63B is a foundational document defining digital authentication best practices, including:
- Discouraging periodic password resets
- Requiring MFA for sensitive actions
- Blocking commonly breached passwords
Best Practices
- Use MFA for all users, especially administrators and remote access
- Start implementing passwordless flows (e.g., WebAuthn, FIDO2)
- Apply adaptive authentication for contextual risk evaluation
- Use centralized identity providers (e.g., Azure AD, Okta)
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