1 Part 1: Fundamentals of the V-Modell

1.5 Project Execution

1.5.2 System Development

The system development includes the development of the »System to be prepared and the development of the »Enabling System required in various system life cycles. For the development, the system is subdivided hierarchically into smaller units until finally a realization is possible. It is subdivided hierarchically into »Segments, »Hardware Units, »Software Unit, »External Units, »Hardware Component, »Software Components, »Hardware Module, »Software Modules, »External Hardware Modules, and »External Software Modules (see »V-Modell Reference Work Products, see Chapter »Structural Product Dependencies).

In accordance with this hierarchical system structure, the system is specified and subdivided into smaller units during the system development. The »Decision Gates depicted in Figure 16 are the basic steps for the refinement of the specification and the subdivision into smaller units.

There is an accurate procedure for every subdivision step, which is based on a uniform pattern and permits a complete tracing of the requirements. During every step, the requirements of the higher »System Elements are taken into account, the subdivision is designed, the realization of the »System Elements is specified, and finally, the requirements are assigned to the next level of »System Elements.

The realization and integration of the system is conducted in reverse order as compared to the specification and subdivision. Based on the realized »Hardware Modules and »Software Module, the more complex »System Elements, and finally the system are integrated. As shown in Figure 16, verification and validation are ensured at every design level.


Figure 16: System Development Structure