Basis & Technology
What is Three-Tier Architecture?
The SAP client-server model separating presentation, application, and database layers.
SAP GUI or browsers form the presentation layer, application servers run ABAP work processes, and the database stores data. Each layer scales independently. Performance testing must consider all three tiers.
Related terms
Application Server
A server instance running SAP application work processes that execute ABAP programs.
Work Process
An operating-system process on an SAP application server that executes requests of a given type, such as dialog or background.
SAP GUI
SAP's desktop client for accessing ABAP systems through classic dynpro screens and transaction codes.
SAP R/3
SAP's client-server ERP system from the 1990s whose three-tier architecture underlies ECC and S/4HANA on-premise.
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Planning an S/4HANA move?
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