Possible Uses
SAP APO can be used either as a stand-alone APS solution, or together with heterogeneous system environments. It is important to differentiate between two different integration concepts:
Introductory Notes
The SAP APO Core Interface (APO CIF) is a standardized interface solution which enables you to integrate the mysap.com component APO Release 3.0A with the following R/3 release levels:
As an R/3 extension, APO-CIF is part of the R/3 Plug-In. The R/3 Plug-In is the common plug-in which interconnects all mySAP.com components with R/3.
For further information, see
R/3 Plug-In.
You should never exceed the Support Package level supported for an R/3 plug-in import. The support package level relevant for an R/3 plug-in is not necessarily identical to a standardized support package for R/3 without the R/3 Plug-In.
For further information see

Ensure that you fully understand the R/3-specific maintenance strategy before applying APO CIF.
For further information, see
Maintenance StrategyIntegration
The APO Core Interface is applied to the R/3 System. Using various Customizing steps, you set up a reciprocal system connection which enables data relevant to the planning process to be transferred from the executing R/3 System to SAP APO, and the results of the planning process to be returned to R/3.
See
Checklist for Setting Up the System Infrastructure for further information.Features
The main roles of the APO Core Interface include: