R12 Applications Architecture
R12 Applications architecture is a three tiered architecture.
The Desktop Tier
The Application Tier
The Database Tier
The Oracle Applications Architecture is a framework for multi-tiered, distributed computing that supports Oracle Applications products. In this model, various servers or services are distributed among three levels, or tiers.
Let us first clarify ourself the important difference b/n the words
SERVER , NODE , MACHINE , TIER
Server : Server is a process or group of processes that run on a single machine and provide a particular functionality.
Tier : A tier is a logical group of services , potentially spread across more than one physical machine.
Machine or node : A machine may be referred to as a node, particularly in the context of a group of computers that work closely together in a cluster.
Desktop Tier :
The Forms client applet must run within a Java Virtual Machine (JVM) on the desktop client. The Sun J2SE Plug-in component allows use of the Oracle JVM on web clients, instead of the browser's own JVM. This is implemented as a browser plug-in.
( In 11i , we use Jinitiator for the for the JVM )
The Application Tier :
Forms services and framework services
Concurrent processing server
Application tier uses two different ORACLE_HOMEs ,
8.0.6 ( 11i) --- > 10.1.2 ( R12 ) AS
8.1.7 ( 11i) --- > 10.1.3 ( R12) AS
Web Services :
Web Services includes the following components
Java Servlet Engine ( OC4J)
Oracle Process Manager (OPMN)
Q) What are self service applications :
Oracle HTML based applications are known as self service applications
Q)What is the diff b/n selfservice applications and applications frame work ?
The oracle applications framework is the development platform for self service applications ( HTML based application )
Forms Services :
Forms services in R12 are provided by the forms listener servlet , which is a more secure deployment over the internet.
Forms listener servlet mediates the communication b/n the desktop client and the oracle database server.
Q) What is forms socket mode ? Does R12 support the socket mode ?
Ans : R12 uses the forms listener servlet mode by default. Howewer , socket mode is still fully supported.
Note : 384241.1
Concurrent Processing Server :
Concurrent Processing is an Oracle Applications feature that allows non–interactive and potentially long-running functions to be executed efficiently alongside interactive operations.
Processes that run on the Concurrent Processing server are called concurrent requests.
When you submit such a request, either through HTML-based or Forms-based Applications, a row is inserted into a database table specifying the program to be run. A concurrent manager then reads the applicable requests in the table, and starts the associated concurrent program.
More detailed explanation on CM characteristics , Types of CMs , setting up the CMs and its architecture will be discussed in a saperate article.
Admin Server :
The Admin (Administration) server is located on the node where you maintain the data model and data in your Oracle Applications database.
Ex : Applying database patches to Oracle Applications , using adadmin to update database tables etc .
Database Tier :
The database tier contains the Oracle database server, which stores all the data maintained by Oracle Applications.
Q) What is oracle applications technology layer ?
The Oracle Applications technology layer lies between the Oracle Applications technology stack and the Oracle Applications product-specific modules. It provides features common to all Oracle Applications products.
This technology layer includes :
Oracle applications DBA ( AD ) -- >used for installing, upgrading, maintaining, and patching the Oracle Applications system.
Oracle applications object library ( FND ) -- >consists of a collection of reusable code, programs, and database objects that provides common functionality across all products.
Oracle applications utilities ( AU ) -- >used to store the files from other products as generating forms and reports may require access to shared PL/SQL libraries.
Oracle common modules ( AK ) -- > used to develop inquiry applications for the HTML-based Applications, without the need for any programming.
Oracle Workflow ( WF ) -- >
Oracle Alerts ( ALR) -- >
Oracle Applications Framework ( FWK ) -- >
Oracle XML Publisher ( XDO ) -- > uses data definitions and templates to produce output reports in the desired format.