To configure a WS-Federation service provider to use the Home Realm Discovery Service, click on the WS-Federation entity name in the OpenSSO Enterprise console, select the Service Provider (SP) tab and configure the following:
Specifies the service so that the service provider can identify the preferred identity provider. The service URL is specified as a contact endpoint by the service provider.
Specifies the identity provider selection mechanism and configuration. Either the cookie or HTTP Request header attribute can be used to locate the identity provider.