The Spiral Model
The Spiral Model founded by the Department of Defense
The main objective of the Spiral Model is to accomodate change in each portion of large products in the Software Development Lifecylce to be elaborated in performance and functionality. The Spiral Model’s has evolved over the years from the Waterfall Model based upon accomodations to prototyping, evaluation of alternative identities and risks in large projects or web applications. The Spiral Model’s software development process combines elements of both design and prototyping-in-stages, in an effort to combine advantages of paradigm architectural directions (top-down and bottom-up concepts). Also known as the spiral lifecycle model (or spiral development), it is Systems Engineering This model of development combines the features of the prototyping model and the waterfall model in the seven baselines of the software engineering lifecycle as follows: (1) Proposal procedures, (2) Planning procedures, (3) Requirements procedures, (4) Design procedures, (5) Development procedures, (6) Test procedures, and (7) Deployment procedures.
A preliminary design is created for all possible and available alternatives, which can help in developing a cost effective project with order to identify and resolve all the possible risks in the project development. Throughout the project, if risks indicate any kind of uncertainty in requirements, prototyping may be used to proceed with the available data and find out possible solution in order to deal with the potential changes in the requirements. Waterfall models do not support changes once the project has launched.