Figure 3.

System architecture. On the server side, CORBA implementation objects access and query the relational database via Persistence^TM, which is a middleware between our CORBA implementation and the Oracle database. To allow invoking operations on the objects, the server provides its clients interfaces in OMG IDL, which is independent of the server implementation. An object's interface is composed of the operations and types of data that can be passed to and from those operations. Clients access the CORBA objects via operation calls through an Object Request Broker (ORB) where the distribution details are handled by the ORB.