Database Reference
In-Depth Information
CHAPTER 2
SAP NetWeaver Application Server ABAP Overview
SAP Business Suite applications run on top of SAP NetWeaver Application Server (SAP NW
AS). SAP business applications could run on NetWeaver Application Server ABAP (NW AS
ABAP), NetWeaver Application Server Java (NW AS Java), or both. SAP ERP 6 is one ex-
ample of a SAP business application that predominantly runs on NW AS ABAP. The SAP
NetWeaver Portal 7.0 application runs on NW AS Java. SAP PI 7.1 (Process Integration) runs
on a dual stack that includes both AS ABAP and AS Java platforms.
This chapter covers the technical architecture foundation of SAP NW AS ABAP from a
conceptual as well as practical perspective. This will help the SAP Basis administrator under-
stand the internals of SAP NW AS ABAP and work on the various system administration
activities of the SAP NW AS ABAP system and support all SAP business applications run-
ning on top of SAP NW AS ABAP.
Chapter 3
will cover the technical architecture founda-
tions of SAP NW AS Java.
Three-Tier Architecture
For best results, the SAP application should be installed as three-tier client-server architec-
ture in production environments. The three-tier architecture is also referred to as a multitier
architecture. In nonproduction environments and smaller business environments, a two-tier
client-server architecture is acceptable as well. In a two-tier architecture both the SAP AS
ABAP and database are installed on one physical machine and the SAP front end on the busi-
ness user's desktop or a laptop. In a three-tier architecture the SAP AS ABAP and database
are installed on separate systems and the front end is installed on the business user's desktop
or laptop. This architecture offers excellent performance and scalability of the SAP solution
for supporting demanding business needs.
The three tiers of the architecture are presentation tier, application tier, and database tier.
The presentation tier includes the SAP front-end components, such as the SAP graphical user
interface (GUI). The application tier includes SAP business logic and is executed on SAP
NW AS ABAP. The database tier includes all SAP-supported relational database systems
such as Oracle, DB2, and SQL Server.
Figure 2-1
shows the three tiers of the SAP architec-
ture.
