Identity Provider (IdP)
Authentication
System that authenticates users and issues tokens/assertions to relying parties (SSO).
Definition
An identity provider authenticates a user and issues authentication assertions or tokens to services (relying parties) to enable single sign-on. It manages sessions, MFA, and account policies.
Why this matters
Why it matters: IdPs are critical infrastructure and concentration points for both security and privacy.
Example
Example: Enforce MFA at the IdP and release only required attributes to each application.