v model testing services qaoncloud

What is the V-Model?

V-model is the most widely used SDLC model. It is also called the Verification and Validation model. In the waterfall model, the testing phase begins after the completion of the development phase. Finding the defects at a very later stage will make it more expensive to fix the defects. So, this model eliminates these costs and for every development phase, there will be a corresponding Testing phase.

The two main Phases in this model are Verification and Validation.

Under Verification phase, we have:

  • Requirements analysis
  • System Design
  • Architecture Design
  • Module Design

Under Validation phase, we have:

  • User acceptance testing
  • System testing
  • Integration testing
  • Unit testing
V model iterations

When to use?

V-model is useful when

  • The project is small to medium size
  • There are well-defined and unambiguous requirements
  • There are enough technical resources available
  • Static tools and technology
  • There is a strict deadline for the project

Testing Phase in the V- model

In V-Model, testing happens hierarchically. On the left side, we have the Verification Phase, i.e., the development activities, and on the right side, we have the Validation Phase, i.e., the testing activities. The coding phase joins both Verification and Validation. The development and testing activities go hand-in-hand. Each activity will have its own deliverables (artifacts). During the Requirement phase, the testing team creates a Requirement Analysis Document and User Acceptance Test Cases. During the system design or the high-level design of the software, the testing team creates a System Test Plan and System Test Cases. In the Architecture design phase, the testing team creates Integration Test Plan and Integration Test Cases. During the Module design or the Low-level design of the software, the testing team creates Unit Test Cases.

Advantages and Disadvantages


  • It saves loads of time

  • It is simple and easy to use

  • Less Risk

  • Testing occurs at every phase

  • It works well for small to medium projects where requirements are well defined


  • Since it is a linear model, this does not suit long term and complex projects

  • It does not include risk analysis activity

  • Difficult to handle concurrent events

  • It cannot adapt to dynamic changes in requirements and presumes static requirements

At QAonCloud, we provide testing services based on your SDLC model and your requirements.