What does APO mean?

SAP APO stands for SAP Advanced Planning and Optimization and is the planning component within the mySAP SCM solution.

Can SAP APO be used as a stand-alone solution?

No, SAP APO always requires a backend ERP system for execution functions. In most cases, the backend system is an SAP R/3 system.

Can SAP APO and SAP R/3 be installed on the same server and use the same database?

No, SAP APO requires a separate server. The actual size of the SAP APO system may vary and depends on the data volume to be processed. 

How does SAP R/3 communicate with SAP APO?

Through the APO Core Interface (CIF) which supplies SAP APO with master and transaction data in real time. CIF is delivered through the R/3 Plug-In, which is something you have to install in your SAP R/3 system. This is the same Plug-In that you need for connecting a BW or a CRM system.

What about the exchange of data between the two systems?

With SAP APO you have a real-time integration to SAP R/3. The minute you change something in one system, it is immediately being transferred to the other and vice versa. And that goes for all data, be it a sales order, a production order or a purchase order. You do not have to perform any batch jobs for transferring data between the systems.

SAP APO is a separate system. Do I have to maintain the master data twice?

No. You create and change master data exclusively in SAP R/3. If you want to work with SAP APO, you need to transfer the master data from the SAP R/3 system. Depending on the scenario you want to use in SAP APO, you may have to enhance the transferred data with SAP APO specific settings, which are not relevant to SAP R/3.