6. Stage 3: design

6.1 Process

This stage enables us to design the architecture of the software system. The solution designed in terms of the user's business, sketched out and retained during the specifications phase, will be imagined taking into account the technical dimension of the IT tools.

This design, to be mastered, is carried out in two stages:

• general (or preliminary) design to determine the overall architecture ;

• detailed design to study each function in greater detail.

Functional and technical choices are distinguished by different levels of granularity, ranging from a global view for general design to a closer view for detailed design.