As you model the structure, you should bear the system infrastructure in mind. Options for distributing enterprise data to R/3 depend on how you allocate R/3 System organizational units to R/3 Systems.

In system distribution scenarios, the instances of R/3 System organizational units are defined in the main system and then distributed to the local systems. This means that the local systems will run a copy of the main instance, which is still located in the main system.

• For cross-system financial statements, the local systems hold copies of the operating concern which was defined in the main system.
• For cross-system cost accounting, the local systems hold copies of the controlling area which was defined in the main system.

In the tile portrayal, copies of an instance are denoted by a prefixed C. This signifies that the original instance will be distributed. Additional arrows show the direction of the data flow.

ALE connections can be documented by adding information concerning the type of data exchanged (IDOCs / BAPIs required). This information can be written next to the arrows or in the pertinent documentation file.