In the illustration, two partner application servers are positioned beneath a load balancer. Arrows indicate that this load balancer serves both application tiers. Beneath the two application servers is the identity management infrastructure--a dotted-line box that contains icons for the single sign-on middle tier, Oracle Internet Directory, and the identity management infrastructure database. To the left of the load balancer and partner application servers is the browser. Arrows show the browser communicating with the load balancer at the effective partner application URL and then being redirected to the identity management infrastructure.