Are federated identity and Single Sign-On (SSO) considered synonymous?

• A. Yes, they are the same
• B. No, they are not synonymous
• C. They refer to different models
• D. Both are outdated concepts

Answer: (B)

Federated identity and Single Sign-On (SSO) are not synonymous because they serve different purposes in identity management systems.

Federated identity is a model that allows users to access multiple applications or services across different domains using a single set of credentials. It enables the sharing of identity information across different security domains, which can involve multiple organizations. This is facilitated through trust relationships established between identity providers and service providers, enabling users to authenticate with their home organization and gain access to third-party services.

On the other hand, Single Sign-On (SSO) refers specifically to the process that allows a user to log in once and gain access to multiple applications without needing to authenticate again for each service. While SSO can be implemented within a single organization, federated identity extends this capability beyond organizational boundaries, allowing users from one organization to access applications and services in another.

Both concepts aim to simplify user authentication and improve user experience, yet they function at different levels of scope and implementation. It is this distinction that makes the statement that they are synonymous inaccurate. Understanding this difference is crucial for anyone working with identity management systems.