The AuthenticationQuery class represents a query for an authentication assertion. When an identity attempts to access a trusted partner web site, a SAML 1.x request with an AuthenticationQuery inside is directed to the authority site.
The Subject of the AuthenticationQuery must contain a SubjectConfirmation element. In this element, ConfirmationMethod needs to be set to urn:com:sun:identity, and SubjectConfirmationData needs to be set to the SSOToken ID of the Subject. If the Subject contains a NameIdentifier, the value of the NameIdentifier should be the same as the one in the SSOToken.