In a SAP system, such as SAP R/3 Enterprise, the client/server architecture is one of the biggest characteristics that allow a system to be scalable and therefore, to grow and adjust to new needs whenever necessary. We can observe three different layers in this architecture, the presentation layer, the application layer and the database layer.
This three-tier architecture can be a two-tier architecture or even a central system (one tier). Depending on the level of scalability and the resources that you require, you may choose one or another strategy.
The presentation layer would correspond to the user’s PC, laptop, or presentation server. The database layer is where the database server can be found.
The application layer ...