
140 n The Art of Software Modeling
In general, the logical structure of the system can be described starting with the
system layers. “Layering” represents the most common form of architecture, where
the system is divided into separate areas of responsibility. A typical layered system
will contain, at a minimum, the following four layers:
Presentation Layer—responsible for the interaction with an external actor;
this is usually in the form of a visual user interface for human users and a
defined communication channel for automated systems.
Business Logic Layer—contains the processing logic used by the system to
provide functionality displayed by ...