What are the authentication options available for end users?

The chosen answer highlights various authentication mechanisms that cater to different security needs and user experiences. Default authentication encompasses the built-in methods provided by an identity solution, while pass-through authentication allows seamless access without repeatedly entering credentials, enhancing usability. Service provider options such as Single Sign-On (SSO) and Security Assertion Markup Language (SAML) facilitate federated identity management, enabling users to access multiple applications with a single set of credentials while ensuring secure communication between identity providers and service providers.

Other options, while valid in their contexts, do not comprehensively cover the range of authentication methods supported by modern identity systems. Basic auth and OAuth2 focus on specific protocols rather than broad user-facing options. Username/password and two-factor authentication, while critical, do not address the interoperability and user experience benefits that SSO and SAML provide. LDAP and database authentication are also essential but represent backend authentication methods rather than end-user options.