Oracle Applications Concepts

The Oracle Applications has three tier Architecture

  •  The Desktop Tier
  •  The Application Tier
  •  The Database Tier
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 installation is made up of the database tier, which supports and manages the Oracle database; the application tier, which supports and manages the various Applications components, and is sometimes known as the middle tier; and the desktop tier, which provides the user interface via an add-on component to a standard web browser.
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. Each tier may consist of one or more nodes, and each node can potentially accommodate more than one tier. For example, the database can reside on the same node as one or more application tier components, for example in a test system. Note, however, that a node is also a software concept, referring to a logical grouping of servers.

Centralizing the Oracle Applications software on the application tier eliminates the need to install and maintain application software on each desktop client PC, and also enables Oracle Applications to scale well with an increasing load

The connection between the application tier and the desktop tier can operate successfully over a Wide Area Network (WAN). This is because the desktop and application tiers exchange a minimum amount of information, for example only field
values that have changed. In a global operation with users at diverse locations, requiring less network traffic reduces telecommunications costs and improves response times.