Spiral testing is a risk based testing, where testers will take risk due many factors at the same time they will equipped with solutions for that risks. In the spiral and rapid application development testing environment there may be no final functional requirements for the system. They are probably informal and evolutionary. In the spiral development environment, software testing is again described as a continuous improvement process that must be integrated into a rapid application development methodology. Testing as an integrated function prevents development from proceeding without testing. Deming’s continuous improvement process using the PDCA model will again be applied to the software testing process.

Starting at the center, each turn around the spiral goes through several task regions:

  • Determine the objectives, alternatives, and constraints on the new iteration.
  • Evaluate alternatives and identify and resolve risk issues.
  • Develop and verify the product for this iteration.
  • Plan the next iteration.

Spiral Model:

As the name implies, spiral model follows an approach in which there are a number of cycles (or spirals) of all the sequential steps of the waterfall model. Once the initial cycle gets completed, a thorough analysis and review of the achieved product or output is performed. If it is not as per the specified requirements or expected standards, a second cycle follows, and so on. This methodology follows an iterative approach and is generally suited for large projects having complex and constantly changing requirements.

The methodology provides a framework for testing in this environment. The major steps include information gathering, test planning, test design, test development, test execution/evaluation, and preparing for the next spiral. It includes a set of tasks associated with each step or a checklist from which the testing organization can choose based on its needs. The spiral approach flushes out the system functionality. When this has been completed, it also provides for classical system testing, acceptance testing, and summary reports.

As spiral methodology is generally a guideline system for solving a problem, with specific components such as phases, tasks, methods, techniques and tools. The spiral model combines the idea of iterative development (prototyping) with the systematic, controlled aspects of the waterfall model. The spiral methodology is the harder choice to plan and budget because of the uncertain nature of how many iterations it will take.