2. Independence of the standard from life cycle models

Since the early 1970s, software development process models have been identified and referred to as lifecycle models. A lifecycle model proposes not only the types of tasks to be performed, but also their sequence.

The waterfall lifecycle mainly identifies the different phases of software production and implements forward chaining for the project by validating each phase before moving on to the next. The disadvantage of this model is that it entails a lot of backtracking, as corrections to previous phases are frequently necessary. Nevertheless, this model remains valid for small-scale projects (with a reduced coding phase), whose requirements are perfectly known and stable, and for which the project team is in control of the difficulties. The standard ISO/IEC12207 can be used to apply this lifecycle model....