What is Basis?
SAP BASIS is a set of the middle ware programs and tools,SAP provides you an underlying interface between FICO,SD to be portable across operating systems and data base.BASIS overlaps with many traditional data base systems GUI(A graphical User Interface).It is the interface in which administrators interacts with the SAP Systems.
Introduction to SAP R/3 Client / Server Technology and SAP R/3 Architecture
SAP has created the architecture in R/3 model that is a three tier client/server model.
- Presentation Server
- Application Server
- Data Base Server
The presentation server is actually a program named sapgui.exe.It is installed on user's workstation.To start that we need to double click the icon on the desktop.When the server started it displays the R/3 menu in a window.This is called as SAP GUI interface.
The Application Server is a set of executable that interpret the ABAP/4 programs and manage input and output.When an application starts,then all the executables all start at the same time and vice versa when it is stopped they all shut down.The number of process that start up when an application server is started can be defined in a single configuration called application server profile.
The database server is a group of executables that accepts the database requests from the application server.This requests are passed to the RDMS(Realation Database Management System).The RDMS send the data to the data base server which then passes the information back toe the application server.Then this inforamtion from applicationserver is passed back to ABAP/4 program.
Configuring the Server
In three-tier client/Server configuration,the presentation,application and database servers all run on different machines.This is the common configuration for all the large systems and also common in production.