What is a relying party?

A relying party is best defined as a service provider that relies on an authentication and authorization service to verify the identity of users accessing its resources. In the context of web technologies, particularly in protocols like WS-Federation, the relying party is the application or service that trusts the assertions made by a central identity provider (IdP).

When a user attempts to access a relying party, the party checks with the IdP to authenticate the user, often through various methods such as token validation or security assertions. WS-Federation, being a protocol designed for federated identity management, enables seamless communication between the relying party and the IdP, making the process of user authentication smoother.

The other options do not align with the definition of a relying party. A user authentication method refers to the techniques for verifying user identities, and a system for granting roles to users focuses on access control mechanisms rather than identity authentication processes. Lastly, a type of report in IDN is unrelated to the concept of a relying party, as it pertains to reporting and analytics rather than the authentication and resource access framework.