Use Windows trust relationship—Specifies whether or not the account partner can use a Windows trust relationship.
Clear the check box if the account partner does not have a Windows trust relationship with this organization.
Selecting this check box enables the Federated Web SSO with Forest Trust design.
All Active Directory Domain Services domains and forests—Specifies that the users can belong to any Active Directory Domain Services (AD DS) domain or forest that is trusted by this account partner.
Specified Active Directory Domain Services domains and forests—Specifies that you want to choose which AD DS domains or forests that are trusted by this account partner are allowed.