Why is pre-configuration necessary

The following illustration of the Appeon migration solution helps explain why these pre-configurations are necessary.

Figure 4. Before and after Appeon Web migration

Before and after Appeon Web migration

Before the Web migration, the heavy client of the target PowerBuilder application interacts with the Database Server. If the application is distributed, the client also interacts with the application server that hosts and executes important business logic for the target application.

After the Web migration, the Web application has an n-Tier Web architecture involving PowerServer as the middleware to hold business logic. This structure is called Browser Server, because the Web application is accessed via Web browsers such as Internet Explorer.

Making the prospective Web application function in an n-Tier Web environment requires more than just hosting the HTML user interface and the business logic on the servers.