API security

Proof-of-Possession Token

A proof-of-possession token is a token that can only be used by the holder that proves possession of an associated cryptographic element.

Definition

A proof-of-possession token strengthens token-based security by requiring the caller to demonstrate control of a bound key or equivalent cryptographic material. This makes simple replay harder than with a bearer-style token alone.

The Ariovis perspective

Tokens are part of an access architecture, not a substitute for identity governance or authorization. Their scope, lifetime, validation and revocation must match the risk of the API and user journey.

These concepts matter most inside a real project.

The first conversation helps establish your context, the systems involved and the next useful decision.