Software Verification and Validation

Although the terms verification and validation are often confused with each other, they are actually processes that must be carried out for every product in every area of our lives. Basically, verification is the confirmation of the fulfillment of product specifications through the provision of objective evidence. Validation proves whether it meets user needs for the finished product. Briefly; the software verification and validation is the process of checking whether the software meets the specifications and requirements for the fulfillment of its intended use. These processes are basically also a good tool to see, evaluate and reduce possible risks after the end of the design process.

the most widely used standard for software as a medical device manufacturers, EN 62304 Medical device software-Software life cycle processes sheds light on the path of software developers in this process. With regulations, guidelines and standards, it is aimed to control the designs of medical device manufacturers throughout the whole process. It has also been a tool to evaluate the accuracy, reliability and effectiveness of the intended purpose of use between the developed device and the device placed on the market.

Different software development models can be used for software development and testing process. The most frequently used of these are Waterfall Model and V-Model.

The Waterfall model software development process consists of processes such as analysis, design, coding, testing, release and maintenance. In software development processes, these processes proceed linearly. The output of each process forms the input for the next process. The negative side is; there is no reverse flow in the waterfall model.

Figure 1. Waterfall software development model

V-model; we can call it a software development process that can be considered as an advanced version of the waterfall model. Instead of moving in a linear direction, the process steps take an upward slope after the coding phase and form the typical V-shape. The V-Model shows the relationships between each phase of the software development lifecycle. This model is a sequential process in which the next stage begins only after the completion of the current stage.

Figure 2. V-Model software development model

The most basic differences between the two software development processes are:

• The Waterfall model is not very flexible and there is no way to return to the previous stage. The V-Model is more flexible.

• While the Waterfall model is a sequential process; V-Model is a simultaneous executable process.

• While the Waterfall model cannot be tested during the software development process; the V-Model can also be tested during the software development process.