Q. Explain about Spiral Model?

The Spiral model is one of the well-liked model used for large projects. This model was projected by Boehm in 1988 and it focuses on minimizing the risk through the use of prototype. We are able to view the Spiral Model as a waterfall model with each stage preceded by Risk analysis stage. The model is separated into four quadrants each with a specific purpose as shown in the fig. Every spiral represents the progress made in the project. In the first quadrant objectives and alternative means to develop product and constraints imposed on the products are identified. The next quadrant compact with identification of risk and strategies to resolve the risks. The third bottom right quadrant goes after the waterfall model. In the bottom left quadrant customer calculates the product requirements are further refined. If at a few stage during the project risk cannot be resolved project is terminated. The model is utilized if the requirements are very complex or several new technology is being introduced by the company.

Advantages:

1. The model tries to resolve every possible risk involved in the project.

2. Every phase of the model enhances the quality of the product.

Disadvantages:

1. The model is suitable merely for large size projects because in some cases the cost of risk analysis may perhaps exceed the actual cost of the project.

2. Expertise in risk management along with project management is essential.

  Spiral Model