A middle-tier instance called Production points to the production environment, Host 1. This host has a master repository that contains a Single Sign-On schema and an OID Schema. The Single Sign-On Server accesses the Single Sign-On schema and communicates with the OID Server, which accesses the OID schema. Host 1 also contains DAS and DIP instances.

The OID server communicates with the test environment, Host 2, through LDAP-based replication. Host 2 contains copies of all of the components of Host 1. A middle-tier instance called Test communicates with Host 2.