For any software to be considered QA verified, it must undergo various processes, starting with comparison. This involves comparing the specification document, customer requirements, and the expectations of the developers and QA team. The program is thoroughly reviewed throughout the implementation process to ensure it aligns with its objectives and delivers the intended benefits to stakeholders.

Verification and Validation:

This review and investigation process is known as Verification and Validation (V&V). It includes prerequisite audits, design and code studies, and rigorous product testing. It is important to note that there is a distinct difference between comparison and confirmation – these are two separate and essential steps in the QA verification process.

Verification ensures the right product is being developed by confirming that it aligns with the specified functional and non-functional requirements.

Verification deals with the question, "Are we building the right product?"

Validation, on the other hand, ensures the product is being built correctly by checking if it functions as intended and meets the expected quality standards.

Validation deals with the question, "Are we building the product right?"

Despite being two different terms, the ultimate goal of these two cycles is to ensure that the product does what it is designed to do. System reliability is determined by a number of different elements.

Verification and Validation (V&V) Approaches:

Within the V&V process, there are two complementary approaches to system checking and analysis:

  1. Software inspections or peer reviews analyze and check system representations such as the
 requirements document, design diagrams and the program source code. Software inspections and automated analyses are static V&V techniques, as you don't need to run the software on a computer.
  2. Software testing involves running an implementation of the software with test data. You examine
 the software's output and operational behaviour to check that it performs as required.
 Testing is now considered a dynamic verification and validation technique as we run software on a computer for the testing process.

There is no hard-and-fast boundary between these approaches to testing, but there are two distinct types of testing that may be used at different
 stages in software development:

  1. Validation testing majorly focuses on the client requirements of the system. In other words, validation testing prioritizes what the customer wants. As part of validation testing, you may use statistical testing to test the performance and reliability of the program and to check how it works under operational conditions.
  2. Defect testing is intended to reveal system defects rather than simulate its operational
 use. The goal of defect testing is to find inconsistencies between a program and its specifications

The level of confidence required for the system doesn't depend only on the verification and validation of QA or the development team. It also depends on the Programming Skills, customers' assumptions of the system, and the system's current marketing environment:

  1. Programming skills: The assurance level required depends on how easy the product is for the organization. For example, the expected confidence level of programming used to maintain a basic security framework is notably higher than that of a model programming framework created to introduce some new ideas.
  2. Customer Assumptions: It is unfortunate that encountering bugs in our system has been considered normal during our product development process. However, conducting root cause analysis has helped us understand the uncertainty regarding the product quality we created. Fortunately, we have noticed a decrease in disappointments compared to before. As a result, we have placed increased importance on creating error-free programming and enhancing our validation and acceptance processes. This approach ensures that we focus on improving the quality of our software and reinforcing a more robust programming process.
  3. Marketing Environment: When marketing a framework, the framework customer should consider competing programs, the value customers will pay for the framework, and the plan required to deliver the framework. If an organization does not have many competitors, they may decide to ship the program before it is fully tested and fixed because they need to get to market first.

V&V and Debugging:

During validation 
testing, you will find defects in the system, and during defect testing, some tests will show that the 
program meets its requirements.

As you discover faults in the program
 you are testing, you must change the program to correct these faults. This process is called debugging. However, testing (or, more generally, verification and validation) and debugging have different goals:

Verification and validation processes are intended to establish the existence of defects in a
 software system and Debugging is a process that locates and corrects these defects

Skilled debuggers look for patterns in the test output
 where the defect is exhibited and use their knowledge of the type of defect, the output pattern, the
 programming language and the programming process to locate the defect. When you are debugging, you
 can use your knowledge of common programmer errors (such as failing to increment a counter) and
 match these against the observed patterns. You should also look for characteristic programming language
 errors, such as pointer misdirection in C.

Locating the faults in a program is not always a simple process since the fault may not be close to the 
point where the program failed. To locate a program fault, you may have to design additional tests that
 reproduce the original fault and pinpoint its location in the program. You may have to trace the 
program manually, line by line. Debugging tools that collect information about the program’s execution 
may also help you locate the source of a problem.

Interactive debugging tools are generally part of a language support tool integrated with a
compilation system. They provide a specialized run-time environment for the program that allows access
 to the compiler symbol table and, from there, to the values of program variables. You can control
 execution by 'stepping' through the program statement by statement. After executing each statement, you can examine the variables' values and thus discover the fault's location.
 After a defect in the program has been discovered, you have to correct it and re-validate the system. This 
may involve re-inspecting the program or regression testing where existing tests are executed again.

Thank you for reading this article. Catch you in the next one.