In this article we are going to learn about why sap is often referred as sap r3 system.
R stands for Real Time data processing. Real time data processing means as soon as an event/ transaction happens data is captured instantaneously and relevant information is updated to all affected parties simultaneously without any time delay.
‘3’ stands for 3 tier architecture.
SAP started in 1972 with 1 tier architecture named R1.
In 1980s SAP launched its improved version on 2 tier architecture called R2.
In 1992 SAP launched advance version on 3 tier architecture called sap R3.
Now let’s understand what is meant by 3 tier architecture.
SAP is software. The way in which software elements and the relationship between them are structured is called software architecture. Architecture is how the software system is designed/ structured. Software system is composed of 3 layers; presentation layer, application layer & data base layer.
Presentation layer is interface between end user and application layer e.g. GUI (graphical user interface). The presentation layer means PCs on which the SAPgui frontend is installed. The interface accepts input from the user in the form of keystrokes, mouse-clicks, function keys and sends these requests to the application server to be processed. The application server sends the results back to the SAPGUI which then formats the output for display to the user.
Application layer consist of collection of executables which collectively interpret ABAP program codes (ABAP is the programming language for SAP). Application layer exist to interpret ABAP codes. It receives request from presentation layer and formats it and then sends it to database layer.
Database layer receives request for data from application layer, passes data from RDBMS (database) to application layer which further passes it to ABAP program. And finally information is displayed on screen through presentation layer.
Tier 1 architecture
All there layers on same server or single machine.
Since all layers loaded on same server/machine hence increased load on server and poor performance.
Client server architecture not possible hence low scalability.
Data loaded on same server/machine hence data security issues.
All layers present on same server/ machine hence software update difficult.
Tier 2 architecture
Presentation layer on separate machines but application layer and database layer present on same server/ machine
Presentation layer present on separate servers/machines. Application layer and database layer still loaded on same server/machine.
Better performance as compared to tier 1 architecture.
Client server architecture is possible hence more scalability.
Since presentation layer is separated hence more secure when compared with tier 1 architecture.
Tier 3 architecture
All layers on separate server/ machine.
Each layer loaded on separate server/machine.
More secure compared to tier 2 architecture.
Since application layer is separated hence this made SAP platform independent which means SAP can run on various platforms. This made SAP compatible with DOS/ UNIX/ LINEX or any other operating system. This feature helped SAP in gaining large customer base.
Question: If SAP IDES is installed on personal computer which does not need internet connection. Will it be an example for tier 1 or tier 2 or tier 3 architecture?
Read more about sap R3 architecture: http://www.guru99.com/learning-sap-architecture.html