V Modell Diagram

The V-Modell is a process model... Similar to the waterfall model, it organizes the development process in phases. In addition to these development phases, the V-Modell also defines the procedure for quality assurance (testing) by contrasting the individual development phases with test phases. On the left side, the process starts with a functional/technical specification, which is expanded in ever greater detail to a technical specification and implementation basis. At the top, the implementation takes place, which is then tested on the right-hand side against the corresponding specifications on the left-hand side. This figuratively creates the eponymous "V", which contrasts the individual development levels with their respective test levels.

Actually, the V model is the waterfall model with a kink.

And almost always the third dimension (in the paper depth, so to speak) is forgotten or overlooked in the sense of configuration management.