claimsbased

Claims-based is an approach to identity management in which a relying party consumes security tokens issued by an identity provider that contain claims about a user. A claim is a statement such as a subject identifier, name, email, role, or other attributes. The token is used to authenticate the user and authorize access to resources, allowing applications to rely on external authentication rather than maintaining their own credentials.

In a typical workflow, a user attempts to access an application, which redirects the user to an identity provider or security token service. After successful authentication, the issuer creates a token containing a set of claims. The relying party validates the token’s integrity and authenticity, extracts the claims, and constructs a user principal used for authorization decisions.

Architecture commonly involves three roles: identity provider (the issuer of tokens), security token service (sometimes the same as the IdP, issuing and describing tokens), and relying party (the application that consumes the token). Trust is established through token signatures and metadata that describe valid issuers and keys.

Standards and technologies frequently associated with claims-based identity include SAML 2.0 and OpenID Connect (which uses JSON Web Tokens). OAuth 2.0 often underpins the authorization flows used in claims-based systems, and in some environments WS-Federation or WS-Trust are used.

Benefits include enabling single sign-on across domains, decoupling authentication from applications, and facilitating federated identities and scalable authorization. Considerations involve managing trust and token lifetimes, ensuring privacy and consent, and handling claim mapping and normalization across identity providers.