Verification and Validation

Verification:

The standard definition of Verification is: "Are we building the product RIGHT?"

Verification is a process that makes it sure that the software product is developed the right way. The software should confirm to its predefined specifications, as the product development goes through different stages, an analysis is done to ensure that all required specifications are met.

During the Verification, the work product is reviewed/examined personally by one ore more persons in order to find and point out the defects in it. This process helps in prevention of potential bugs, which may cause in failure of the project.

Validation:

Validation is a process of finding out if the product being built is right?

Whatever the software product is being developed, it should do what the user expects it to do. The software product should functionally do what it is supposed to, it should satisfy all the functional requirements set by the user. Validation is done during or at the end of the development process in order to determine whether the product satisfies specified requirements.

All types of testing methods are basically carried out during the Validation process. Test plan, test suits and test cases are developed, which are used during the various phases of Validation process. The phases involved in Validation process are: Code Validation/Testing, Integration Validation/Integration Testing, Functional Validation/Functional Testing, and System/User Acceptance Testing/Validation.

Activities included in Verification and Validation Process:

The two major V&V activities are reviews, including, inspections and walkthroughs, and testing.

Reviews:
Reviews are conducted during and at the end of each phase of the life cycle to determine whether established requirements, design concepts, and specifications have been met. Reviews consist of the presentation of material to a review board or panel. Reviews are most effective when conducted by personnel who have not been directly involved in the development of the software being reviewed.

Inspection:
Inspection involves a team of about 3-6 people, led by a leader, which formally reviews the documents and work product during various phases of the product development life cycle. The work product and related documents are presented in front of the inspection team, the members of which carry different interpretations of the presentation. The bugs that are detected during the inspection are communicated to the next level in order to take care of them.

Walkthroughs:
Walkthrough can be considered same as inspection without formal preparation (of any presentation or documentations). During the walkthrough meeting, the presenter/author introduces the material to all the participants in order to make them familiar with it. Even when the walkthroughs can help in finding potential bugs, they are used for knowledge sharing or communication purpose.

Testing:
Testing is the operation of the software with real or simulated inputs to demonstrate that a product satisfies its requirements and, if it does not, to identify the specific differences between expected and actual results. There are varied levels of software tests, ranging from unit or element testing through integration testing and performance testing, up to software system and acceptance tests.