Ways to Distribute Master Data 
The graphic below is an example of how master data is distributed:
The graphic on the left shows the simplest case:
· All the master data is created in a central system and is then distributed to the local systems.
For example, the materials A, B and C are created centrally; A and B are then distributed to one decentralized system, whilst B and C are distributed to another decentralized system.
The graphic on the right shows a hierarchy of three layers:
· Master data can be created in several different systems. A central SAP system is used as a reference point for the other systems.
For example, the materials A and B are created in one system, whilst C and D are created in a second system. In each case the materials are also distributed to the reference system. They are distributed to the client systems.
In principle, master data can be freely distributed between all the SAP systems. A central SAP system is not necessary, but it does make the distribution of the master data easier.