The document discusses several software development models: waterfall, incremental, and spiral. The waterfall model is a linear sequential process that flows from requirements to maintenance without backtracking. Incremental models divide projects into smaller parts to develop working software more quickly. The spiral model organizes activities in a spiral shape with four quadrants focusing on risk assessment, alternatives evaluation, development/verification, and technical reviews.

1. Software Development Models MuwaffaqSalman ShanatanuTyagi Brian Simmons Mark Quinn

2. Software Development Process A software development process or life cycle is a structure imposed on the development of a software product There are several models for such processes Each model describes approaches to a variety of tasks or activities that take place during the process.

3. Some Development Models Waterfall Model Incremental Model Spiral Model

5. It is a linear and sequential software development process

6. It consists of phases such; as 1)Requirements analysis, 2)Design, 3)Implementation, 4)Testing, 5)Installation, 6)Maintenance

8. Disadvantages of Waterfall Model It is seen as somewhat unrealistic and unsuitable for the real world because of it’s upfront requirements Inflexible as it’s difficult revisit phase once it’s completed phase Costly to change scope and requirements

10. The Incremental model gives a particular amount of risk containment. Unless a problem was universal it would not hold up the perfect development process as the other components would still continue to develop in self-supporting

11. There are 2 incremental models as seen in figure 1 and figure 2

13. Disadvantages of Incremental Model Each phase of an iteration is rigid and do not overlap each other Problem may arise pertaining to system architecture because not all requirements are gathered up front for the entire software life cycle

15. Activities are organised in a spiral shape and divided into four quadrants

16. First Quadrant: focuses on gathering an understanding of the objectives

17. Second Quadrant: is to evaluate any alternatives and identify risks associated with these alternatives

18. Third Quadrant: If performance and other technical and operational issues are resolved the activities to develop and verify next-level product are performed

20. Disadvantages of Spiral Model Limited reusability Risk of not meeting deadlines or exceeding budget Possibility to end up using the waterfall model