APPS Architecture

Desktop tier    

A client could access the Oracle Applications only by using a Web Browser which must have Oracle JInitiator installed on it. Oracle JInitiator is the Oracle Java Virtual Machine used to run Oracle Forms applets.

Application (or middle) tier includes 

• Web Server:  listens for HTTP requests and provides an HTTP response to the client. The HTTP response usually consists of an HTML document, but can also be a raw file, an image or some other type of document (defined by MIME-types);

 

• Forms server: includes the Forms listener and the Forms Runtime Engine. The Forms Runtime Engine maintains a connection to the database on behalf of the Java client. It uses the same Forms, Menus, and Libraries files that are used for running in client/server mode. No application code changes are required to deploy a legacy client/server application to the Internet;

 

• Concurrent Processing Server: server which run reporting programs and data updating programs (periodically or ad hoc). These programs (named concurrent programs) run on this server in background in order not to interfere with the normal operations. When a request is made a row is inserted into FND_CONCURRENT_REQUEST table. The concurrent managers read these requests in the table and start the relevant concurrent programs;

 

• Reports Server:   run Oracle Applications reports and is always installed on the same node as the Concurrent Processing Server. However the reports are administered separately from the concurrent processing reports; 

 

• Administration Server:  contains scripts which are used to administer the Oracle Applications eBusiness Suite. From this server the following operations can be performed:

•  Applying patches (using adpatch);
•  Maintaining Oracle Applications (using adadmin);
•  Upgrading Oracle Applications from an earlier release to  11.5.x (using adaimgr).

• Discoverer Server (optional):  is installed if Oracle Discoverer will be used.

Database tier 

    

The Database tier contains the Oracle Database Server which store all the data needed by Oracle Applications. The database store the Oracle Applications online help as well. The database server communicate with middle tier and does not communicate directly with the desktop tier.