The diagram below illustrates the architecture of the migrated application and the application is structured into the following three layers.

Three-Layered Services Application, as presented here, is basically a relaxed three layered architecture. The three layers are:

Presentation
The presentation layer provides the application’s user interface (UI). Typically, this involves the use of Windows Forms for smart client interaction, which is extracted from PowerBuilder™ Window and Datawindow Presentation logic.

Business
The business layer implements the business functionality of the application. The domain layer is typically composed of a number of components implemented using PowerMigrator™ tool, process and methodology to convert PowerBuilder™ code in to equivalent VB.NET™ components, which will be augmented with PowerMigrator™.NET™ framework. This will be deployed on the core Microsoft® .NET™ platform for scalable distributed component solutions and optionally with Microsoft BizTalk® Server for workflow orchestration.

Data
The data layer provides access to external systems such as databases. The primary .NET™ technology involved at this layer is ADO.NET™

1. In memory structure is nothing but the datawindow buffer and related logic has been migrated to data set which is an integral part of ADO.NET™
2. Data access logic, data update logic like insert, update and delete logic is an integral part of the datawindow. This logic will be extracted and implemented in .NET™ using Data Adapter, which is again an integral part of ADO.NET™.
3. Conventional PowerBuilder™ application is used to connect to the database typically using, either Native or ODBC driver, which will be migrated to data connection object in ADO.NET™. We will also take care to use .NET XML as a part of our migration, which will enable the migrated VB.NET™ component to server as Web service component.
4. In memory structure is nothing but the datawindow buffer and related logic has been migrated to data set which is an integral part of ADO.NET™.
5. Data access logic, data update logic like insert, update and delete logic is an integral part of the datawindow. This logic will be extracted and implemented in .NET™ using Data Adapter, which is again an integral part of ADO.NET™.