The Verification and Validation model commonly known as V Model is considered to be an extension of the Waterfall model. This is because just like the waterfall model, it’s a welltructured method in which the different phases progress in a sequential or linear way. That means each phase begins only after the completion of the previous phase.

An important aspect of this model is that testing activities like planning, test designing happens well before coding. The advantage is that it saves ample amount of time and since the testing team is involved early on, they develop a very good understanding of the project at the very beginning.

The biggest disadvantage of V-model is that it’s very rigid and the least flexible. If any changes happen mid way, not only the requirements documents but also the test documentation needs to be updated. Even with these disadvantages, it’s the most favored software development process as it’s simple and easy to use.