Framework Architecture

The framework architecture of SAP CRM is based on different software layers. The figure below illustrates the framework architecture and its different software layers:

The different software layers are completely separated from each other. This separation allows the connection of any business application, via business object layer (BOL) and generic interaction layer (genIL) to the presentation layer.

Presentation Layer

The presentation layer of the CRM WebClient UI is based on the CRM User Interface Framework (CRM UIF), which is the basis for the HTML pages running in the Web browser.

Business Layer

The business layer of the CRM WebClient UI consists of the following software layers:

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  Business object layer (BOL)

  
  

  The business object layer saves the business object data, for example of sales orders, at runtime of the SAP CRM session. This layer guarantees the separation of the CRM WebClient UI and the underlying business logic.

  
  


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  Generic interaction layer (genIL)

  
  

  The generic interaction layer handles the data transfer from the business object layer to the application programming interfaces (APIs) of the underlying business engine. It is the connection between the business object layer and the underlying business engine.

  
  

Business Application

The business application contains the business logic and the database tables.

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Source: http://docphy.com/technology/computers/software/framework-architecture.html