This illustration contains an exploded view of a directory information tree for an application service provider named The tree shows two realms, dc=realm1 and dc=realm2. Only the first is expanded. It contains the captions cn=users and Realm & User Metadata. Next to the exploded view is an icon representing the identity management infrastructure. Above this icon is the browser and a reproduction of the single sign-on login page, showing the realm login field. To the right of the browser is an icon representing the single sign-on middle tier with mod_osso inset.