Search results
Results From The WOW.Com Content Network
The waterfall model provides a structured approach; the model itself progresses linearly through discrete, easily understandable and explainable phases and thus is easy to understand. It also provides easily identifiable milestones in the development process, often being used as a beginning example of a development model in many software ...
According to Royce in the process model "the design iterations are never confined to the successive step", and for that model without iteration is "risky and invites failure". [3] As alternative Royce proposed a more incremental development, where every next step links back to the step before. The 'classical' waterfall model is figure 2.
An example of waterfall charts. Here, there are 3 total columns called Main Column1, Middle Column, and End Value. The accumulation of successive two intermediate columns from the first total column (Main Column1) as the initial value results in the 2nd total column (Middle Column), and the rest accumulation results in the last total column (End Value) as the final value.
Rapid application development was a response to plan-driven waterfall processes, developed in the 1970s and 1980s, such as the Structured Systems Analysis and Design Method (SSADM). One of the problems with these methods is that they were based on a traditional engineering model used to design and build things like bridges and buildings.
In software development, the V-model [2] represents a development process that may be considered an extension of the waterfall model and is an example of the more general V-model. Instead of moving down linearly, the process steps are bent upwards after the coding phase, to form the typical V shape.
This model combines the elements of the waterfall model with the iterative philosophy of prototyping. According to the Project Management Institute , an incremental approach is an "adaptive development approach in which the deliverable is produced successively, adding functionality until the deliverable contains the necessary and sufficient ...
Get AOL Mail for FREE! Manage your email like never before with travel, photo & document views. Personalize your inbox with themes & tabs. You've Got Mail!
In later publications, [1] Boehm describes the spiral model as a "process model generator," where choices based on a project's risks generate an appropriate process model for the project. Thus, the incremental, waterfall, prototyping, and other process models are special cases of the spiral model that fit the risk patterns of certain projects.