Oracle Applications Architecture:
The Desktop Tier
The client interface is provided through HTML for HTML-based applications, and via a Java applet in a Web browser for the traditional Forms-based applications.
In Oracle Applications Release 12, each user logs in to Oracle Applications through the
E-Business Suite Home Page on a desktop client web browser. The E-Business Suite
Home Page provides a single point of access to HTML-based applications, Forms-based applications, and Business Intelligence applications.
Once logged in via the E-Business Suite Home Page, you need not sign on again to access other parts of the system. Oracle Applications does not prompt again for user name and password, even when you navigate to other tools and products. Oracle Applications also retains preferences as you navigate through the system.
For example, if you registered in the E-Business Suite Home Page that German is your preferred language, this preference carries over whether you access Forms-based or HTML-based applications.
The Application Tier
The application tier has a dual role: hosting the various servers and service groups that process the business logic, and managing communication between the desktop tier and the database tier. This tier is sometimes referred to as the middle tier.
Four servers or service groups comprise the basic application tier for Oracle Applications:
• Web services
• Forms services
• Concurrent Processing server
• Admin server
The Database Tier
The database tier contains the Oracle database server, which stores all the data maintained by Oracle Applications. The database also stores the Oracle Applications online help information.
More specifically, the database tier contains the Oracle data server files and Oracle
Applications database executable that physically store the tables, indexes, and other database objects for your system.
The database server does not communicate directly with the desktop clients, but rather with the servers on the application.
