1. General principle

1.1 Separation between interface and application

Applications are no longer developed in a monolithic way, but are broken down into modules whose organization is based primarily on the organization of processing.

In addition to this practice, good architecture means rigorously and effectively breaking down the application into two parts:

• its functional core, itself organized into modules ;

• interface.

The separation of interface and functional core is in line with program modularity, which is a rule of good practice in software engineering (figure