The terms "verification" and "validation" are very often used in the technical literature and are associated with the analysis of the quality of any software. In the scientific literature you can find various interpretations of these concepts. So, let's try to understand this issue.
The most correct, from our point of view, is the following definition. Validation and verification are activities that are aimed at conducting quality control of a software product in order to detect errors in it in the early stages. It would seem that they have a common goal. But still, these species have differences in the sources of the tested properties, restrictions and rules, the non-observance of which may be considered a mistake.
Verification is the verification of software compliance with technical documentation provided by the terms of reference , architecture or domain model. The “duties” of this term also include comparing the settlement procedure with the process of their development, rules and standards.
Data verification can be performed to establish compliance of the program with established standards, requirements, design decisions and user documentation. At the same time, those documents with which they are compared for compliance with their standards and norms established in the country where the software is used are subject to mandatory preliminary verification. It is necessary to take into account and compliance with all sequences of operations.
If an error or defect in the program’s work is found, or if a contradiction between the above documents and the current functioning of the program is detected, the decision to choose a document for correction should be a solution to a separate problem.
In contrast to verification, validation is responsible for verifying that developed or maintained software products meet the needs or needs of customers or users. These needs are often not recorded in any documentation. That is why validation is less formalized than verification. This is a process in which the representative of the customer, user is involved, and an analyst or subject matter expert may also be present . In other words, those that can express the specific needs and real needs of stakeholders.
Verification is the answer to the question “Is the software executed correctly?”, And the validation is “Is the correct software made?”.
When searching for the answer to the questions posed, it can be found that validation (or certification) in content is somewhat broader than verification (verification). However, verification is closely related to ensuring quality control of a software product.
For example, verification of a computer program involves a process in which the goal is to ensure that the requirements of the data received in a certain product life cycle are satisfied with those that were obtained at the previous stage.
If we are talking about model verification, then we will talk about checking the correctness of the mapping of this computational model to the necessary conceptual or mathematical models.
When verifying the system code, the source encoding is analyzed and its documentary description is checked.
During the verification process, operations containing alternative calculations may be included. The technical and scientific documentation of the new project is compared with the corresponding documentation of an existing project, mandatory testing, testing of a new software product and demonstration of the results.