Introduction:- Being a core Oracle DBA we have deep knowledge of Oracle Database Architecture. In any architecture, we go through the proper function. After having a good knowledge of database architecture we must work beyond of it. In this article, we are going o have a tour of Oracle Application R12c architecture. This architecture is totally different from Oracle database’s architecture.
Overview of Three Tier Architecture Overview of Three Tier Architecture
- A tier is a logical grouping of services potentially spread across more than one physical machine.
- The three-tier architecture that comprises an Oracle E-Business Suite is made up of the Desktop Tier (The Client Interface), Application Tier (Various servers and service groups that process business logic), Database Tier (Oracle database server).
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.
Application Tier
The Application Tier various servers and service groups that process the business logic, and managing communication between the desktop tier and the database tier. Four servers or service groups comprise the basic application tier for Oracle Applications:
- Web services
- Forms services
- Concurrent Processing server
- Admin server
Client Client
Sun 1.5 Java Runtime Environment (JRE) i.e.
Java Virtual machine (JVM) : J2SE Plug-in
Middle Tier
- Apache Web Server 2.0
- JRE (Java Runtime Environment)1.5
- JDK (Java Development Kit)1.5.X
- Oracle Containers for J2EE (OC4J)
- Oracle Process Manager and Notification Server
- Oracle Forms/Reports 10g
Database Tier
Oracle 10g Enterprise Edition
Web Services
The Web services component processes requests received over the network from the desktop clients, and includes the following components:
- Web Listener (Oracle HTTP Server powered by Apache)
- Java Servlet Engine (OC4J)
- Oracle Process Manager (OPMN)
The Web listener component of the Oracle HTTP server accepts incoming HTTP requests from client browsers and routes the Requests to the appropriate OC4J container.
Form Services
- Forms services in Oracle Applications R12 are provided by the Forms Listener Servlet.Forms services in Oracle Applications R12 are provided by the Forms Listener Servlet.
- The Forms Listener servlet is a Java servlet that delivers the ability to run Oracle Forms applications over HTTP or HTTPS connections.The Forms Listener servlet is a Java servlet that delivers the ability to run Oracle Forms applications over HTTP or HTTPS connections.
- It hosts the Oracle Applications forms and runtime engine hosts the Oracle Applications forms and runtime engine.
- It communicates between the desktop client and the Oracle database server for displaying client screens.It communicates between the desktop client and the Oracle database server for displaying client screens.
Forms-based Desktop Tier Architecture
Overview of Forms Socket Mode Architecture
HTML-Based Applications Architecture
Oracle Applications Framework Architecture
Oracle Applications Processing Servers
Concurrent Processing Server
- In Concurrent processing, the programs runs in the background while users continue to work on other tasks In Concurrent processing, the programs runs in the background while users continue to work on other tasks.
- It uses operating system facilities to facilitate background scheduling of data- or resource- intensive jobs, via a set of programs and forms It uses operating system facilities to facilitate background scheduling of data- or resource- intensive jobs, via a set of programs and forms
- All these concurrent programs runs on Concurrent Processing serverAll these concurrent programs runs on Concurrent Processing server
- Processes that run on the Concurrent Processing server are called Concurrent RequestsProcesses that run on the Concurrent Processing server are called Concurrent Requests
Admin Server
The Admin server is located on the node where you maintain the data model and data in your Oracle Applications database. You carry out the following operations from this server:
- Applying database patches to Oracle Applications
Applications patches consist of files and scripts that update the file system and database objects .
- Maintaining Oracle Applications data
The AD Administration utility enables you to carry out this and various other file system and database maintenance tasks.
Concurrent Managers
Responsibilities of Concurrent Managers are mention below:-
- Managing Execution of Concurrent Program
- Managing the programs completion status
- Interaction with host concurrent program
- Tracing a concurrent program
- Optimization options
- Managing the printer
Types of Concurrent Managers
- Internal Concurrent Manager :- The Internal Concurrent Manager (ICM) controls all other concurrent managers. It administers the startup and shutdown of managers as defined by their work shift, monitors for process failure, and cleans up if a failure occurs.
- Standard Manager :- The Standard Manager will accept and run any concurrent requests, as it has no specialization rules that would restrict its activities.
- Conflict Resolution Manager :- The Conflict Resolution Manager (CRM) ensure that incompatible concurrent requests do not run in the same conflict domain.
Load Balancing
The application tier supports load balancing among many of its servers and services to help provide higher availability, fault tolerance, reliability, and optimal scalability . If you have more than one of any of the following types of server, load balancing can be employed:
- Web services
- Forms services
- Concurrent Processing server
Summary :- Oracle Applications have three-tier architecture. They are comprised of a Database tire which manages the Oracle database and stores all data; an Application tier which hosts various servers, manages communication between the desktop and database tier and contains the applications file system; and a client Desktop through which users access Oracle Applications.
