Application Server Advantages

1) It reduce load on the database

2) The user requests are queued installed of hitting the database directly.

3) The user requests are provided with dedicated resources on the all the Application Servers.

4) Most frequently used data is buffered.

5) Database clients are installed on the application server their by reducing load on the

   clients.

----> SAP adapts 3 tire architecture and it has its own usage for each layer.