Token introspection is the process of asking an authorization service for the current validity and metadata of a token before trusting it. It matters because some systems need live token state instead of relying only on self-contained claims.
What is Token Introspection?
With token introspection, a resource server queries an authorization component to determine whether a token is active and what attributes or permissions are associated with it. This can help with revocation-aware enforcement, central policy checks, and tighter control over opaque tokens.
What Token Introspection Commonly Supports
Common uses include opaque tokens, revocation-sensitive APIs, centralized policy enforcement, and systems needing stronger real-time trust checks.
Token Introspection vs. Offline JWT Validation
Offline validation trusts embedded claims locally. Token introspection asks a central authority for live token state before allowing access.
Frequently Asked Questions
Why is token introspection useful?
Because it can provide fresher token status and stronger revocation awareness than purely offline validation.
Does introspection always make sense?
Not always. It adds dependency and latency, so some systems prefer self-contained tokens when real-time status is less critical.
Related Cybersecurity Terms
