Prototyping Model

1.    In prototyping model initially the requirement gathering is done.

2.    Developer and customer define overall objectives; identify area needing more requirement gathering.

3.    Then a quick design is prepared. This design represents what will be visible to the user-in input and output format.

4.    From the quick design a prototype is prepared. Customer or user evaluates the prototype is order to refine the requirements. Iteratively prototype is tuned for satisfying customer requirements.

5.    When working prototype is built, developer use existing program fragments or program generators to throw away the prototype and rebuild the system to high quality.

6.    Certain classes of mathematical algorithms, subset of command driven systems and other applications where results can be easily examined without real time interaction can be developed using prototyping paradigm.

Benefits of prototyping model

1.   Software applications that are relatively easy to prototype almost always involve human-machine interaction (HCI) the prototyping model is suggested.

2.   A general objective of software is defined but not detailed input processing or output requirements. Then in such a case prototyping model is useful.

3.   When the developer is unsure of the efficiency of an algorithm or the adaptability of an operating system then prototype serves as a better choice.

Disadvantages of prototyping model

1.   In the first version itself, customer often wants “few fixes” rather than rebuilding of the system. Whereas rebuilding of new system maintains high level of quality.

2.   The first version may have some compromises.

3.   Sometimes developer may make implementation compromises to get prototype working quickly. Later on developer may become comfortable with compromises and forget why they are inappropriate.