Software testing Methodologies

Waterfall model: It is a linear sequential model. The basic steps involved in this software testing methodology are:

In this methodology, you move on to the next step only after you have completed the present step. There is no scope for jumping backward or forward or performing two steps simultaneously. The main benefit of this methodology is it's simplistic, systematic.

Disadvantages:  In this model there is no back tracking. For example if any error occur any Stage of software development, it can't be corrected in that build.

V-Model: V-model is a software development model. Instead of moving down in linear way (as waterfall) the process steps are bent upwards after the coding phase, to form typical 'V' shaped.The V-model demonstrates the relationship between each phase of the development life cycle and its associated phase of testing. This is also called verification validation model.

 

Spiral Model: As the name implies, the spiral model follows an approach in which there are a number of cycles of all the linear steps of the waterfall model. This model of development combines the features of the prototyping model & waterfall model. This methodology follows an iterative approach and is generally suited for very large projects having complex and constantly changing requirements.

The steps in the spiral model can be generalized as follows-

• The new systems requirements are defined in as much details of possible.
• A preliminary design is created for the new systems.
• A first prototype design of new systems is constructed from the preliminary design.

Prototype Model: This model allows the client to interact and experiment with a working representation of the product. The developmental process only continues once the client is satisfied with the functioning of the prototype. Development of the prototype obviously undergoes design, coding and testing. But each of these phases is not done very formally or thoroughly. By using this prototype, the client can be able to understand the requirement for the desired system