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About the Siebel Object Architecture

The metadata that defines Siebel CRM objects and other files, such as web templates and style sheets, is divided in several architectural layers. Figure 5 illustrates the architecture.

Figure 5. Siebel Object Architecture

The architecture includes the following layers:

1. Physical user interface objects layer. Includes the physical files, templates, style sheets, and other metadata that reference files that render the user interface in the Siebel client.
2. Logical user interface object layer. Includes object definitions for the user interface in the Siebel client. These objects define the visual elements that Siebel CRM displays to the user and with which the user interacts in a Web browser. A user interface object references a business object.
3. Business object layer. Includes objects that define business logic and organizes data from underlying tables into logical units.
4. Data objects layer. Includes object definitions that directly map the data structures from the underlying relational database to Siebel CRM. These objects provide access to those structures through object definitions in the business object layer.

Siebel CRM insulates objects in each layer of the Siebel object architecture from the layers above and below each layer, including the RDBMS (Relational Database Management System) at the bottom of the architecture. This allows you to change or customize Siebel objects in one layer without affecting other layers. Because Siebel CRM separates the database in the RDBMS from the object architecture, you can make database changes with only minimal affect on Siebel CRM.

For more information, see Configuring Siebel Business Applications.

About the Sequence You Use to Define Objects

It is useful to think of configuration tasks in terms of the Siebel object architecture. You might work from the bottom up, starting with data objects first, then business objects, and then user interface objects. Or you might work in one layer only, modifying objects as needed. For the NREC example in this book, you modify objects in the user interface layer first.