About SP-initiated SSO with the SamlFederationHandler
SP-initiated SSO occurs when a user attempts to access a protected application directly through the SP. Because the user’s federated identity is managed by the IDP, the SP sends a SAML authentication request to the IDP. After the IDP authenticates the user, it provides the SP with a SAML assertion for the user.
The following sequence diagram shows the flow of information in SP-initiated SSO, when PingGateway acts as a SAML 2.0 SP: