Client programs of external applications access SAP business objects by making OLE Automation calls to the BAPI ActiveX control which forwards requests via Remote Function Call (RFC) to the Business Object Broker (BOB) in the Business Object Repository (BOR), as shown in the following graphic:

When a client program calls a method, the BAPI ActiveX control looks for an appropriate BAPI method. If a BAPI method exists, the BAPI ActiveX control calls the relevant function module directly. Otherwise, access is through the BOR.

Making OLE Automation calls to BAPI function modules directly through the BAPI ActiveX control is faster, because it avoids the overhead involved in requesting a method invocation.