Verification And Validation in Software Engineering: In software testing, verification and validation are the processes to check the correctness of the product. Verification and validation in software engineering is a set of methods that enhances the quality of testing. There are different means and criteria to that end. This article will explain all those in detail, along with some examples and cases, and the best practices for hiring the right experts.
Verification is a process to check that software meets specific requirements and should be done before delivery or deployment into a live environment.
Validation is the process of checking whether the system has fulfilled all its intended purposes without any flaws for a given set of test cases and inputs. These processes are part of the Software development life cycle and V Model.
What is Verification?
Verification is the process of evaluating software during development and testing to determine whether it meets its specified/intended requirements.
The purpose of verification is to validate that the coding, unit test, integration test, system test (if applicable), user acceptance test, etc has been performed correctly using a sufficiently rigorous standard or set of standards.
Verification is intended to provide an independent review of the software development process.
Purpose of Verification: The purpose of verification is to validate that the work products and deliverables, as well as activities and processes during software development, have been performed correctly by using a sufficiently rigorous standard or set of standards.
The ultimate purpose of verification is to confirm or contradict the original intent and expectations established for a project.
What is Validation ?
Validation is the process of evaluating the software to determine whether it satisfies its specified requirements. While verification deals with an approach to meet these expectations, validation assesses whether project objectives have been fulfilled by checking actual performance against specified requirements.
The purpose of validation is to ensure that the final system matches a predetermined set of criteria for completeness, correctness, usability, and applicability.
Verification and Validation (V&V) are two different processes with the same objective of validating software correctness. However, verification is a subset of validation to be performed before delivering/deploying the software into a live environment. The latter includes additional checks like integration, performance, and safety testing which will be performed in a production-like environment.
Verification VS Validation
Now we are going to look what is the difference between Verification And Validation:
Verification:
- Verification is a process to check that software meets specific requirements and should be done before delivery or deployment into a live environment.
- Verification includes all checks done to ensure the system works as intended, according to requirements and specifications.
- Is done to evaluate whether the product meets a specification e.g. requirements, design document
- Is performed by internal testers, developers as well as the client.
- Might or might not be performed by testers
- Involves running the application with test cases.
- Identifying different kinds of defects (functional, performance, usability, security) that may exist in the application.
- Eventually, identifying what needs to be fixed prior to deployment.
- Is the last step prior to deploying an application.
- Emphasizes the process and not necessarily the quality of the end product.
Validation:
- Validation is the process of checking whether the system has fulfilled all its intended purposes without any flaws for a given set of test cases and inputs. These processes are part of the Software development life cycle.
- Validation is performed after verification assuring that the application does not pose any risk for its users or client’s environment.
- Is performed after verification to confirm that the application does not pose any risk for its users or client’s environment.
- Is performed by internal and external testing teams.
- Involves running the application with test cases with a focus on bringing defects to light at this stage.
- Is performed by testers with a focus on discovering defects in the application.
- Involves running test cases with a scope of testing that is beyond what was done during verification.
- Can be seen as the last and most important step of development life cycle.
- Emphasizes the product/application quality.
And when we are discussing different software development models that are: Waterfall or Rational Unified Process (RUP) or Agile development we can see differences in Verification and Validation of these models:
- In waterfall model, testing is done at the end of the development cycle and validation is performed after testing.
- In Rational Unified Process model, verification is done at the end of each level in development cycle and validation is done after verification.
- In the Agile model, testing and validation are performed at each stage in the development cycle.
Conclusion:
The purpose of validation is to ensure that the final system matches a predetermined set of criteria for completeness, correctness, usability, and applicability. Validation means checking whether testing was done properly and it can be performed in several ways: by using automation tools (e.g., unit tests), manually using test cases to check if some requirements are not broken, by performing stress testing, functional testing, and non-functional testing.
I hope this detailed post about the difference between Verification And Validation gives a clear idea for all. I’ll post more about Software Testing in the coming days. Do you have any queries please feel free to ask in the comment section.
