5. Formalizing requirements

Gather together all the functions and constraints at each stage in the life cycle of the solution under study in a "functional specifications document – CDCF". This will help you validate whether alternative solutions meet each performance requirement.

Depending on the case, the completeness of the CDCF may vary: a CDCF that is incomplete at the end of an initial functional analysis may (or must) be completed (new functions, more precise criteria, etc.), during the cost analysis (certain costs being linked to performances not yet expressed), or even at the time of validation of alternative solutions (the stakeholders then expressing additional reasons for accepting or rejecting a solution).

The CDCF is the result of a functional analysis, which can be used to specify a requirement to a supplier, as a basis for optimizing the solution through...