Prototype model of SDLC
- 1. PROTOTYPE MODEL By Kumar Sethi
- 2. Need of Prototype Model • Even a small change in any previous stage can cause big problem for subsequent phases as all phases are dependent on each-other. • Real projects rarely follow the sequential flow. • Poor model for long and ongoing projects. WHY? As we freeze software and hardware in this model, but technology changes rapidly, such freezing is not advisable for long term projects. • Not a good model for complex and object-oriented projects. • Not suitable for the projects where requirements are at a moderate to high risk of changing. • It is difficult to measure progress within stages. Based on the previous model disadvantages :-
- 3. Prototype Model • This model requires before carrying out the development of the actual software, a working prototype of the system should be built. • A prototype acts as a sample to test the process. From this sample we learn and try to build a better final product. • A prototype is a model or a program which is not based on strict planning, but is an early approximation of the final product or software system. • This type of System Development Method is employed when it is very difficult to obtain exact requirements from the customer (unlike waterfall model, where requirements are clear). • While making the model, user keeps giving feedbacks from time to time and based on it, a prototype is made. • Completely built sample model is shown to user and based on his feedback, the SRS (System Requirements Specifications) document is prepared.
- 4. Prototype Model • After completion of this, a more accurate SRS is prepared, and now development work can start using Waterfall Model, the goal is to provide a system with overall functionality. • Diagram
- 5. Advantages • Users are actively involved in the development • Since in this methodology a working model of the system is provided, the users get a better understanding of the system being developed. • Errors can be detected much earlier. • Quicker user feedback is available leading to better solutions. • Missing functionality can be identified easily • Time required to complete the project after getting final the SRS reduces, since the developer has a better idea about how he should approach the project.
- 6. Disadvantages • It is a slow process. • Too much involvement of client, is not always preferred by the developer. • Too many changes can disturb the rhythm of the development team. • Practically, this methodology may increase the complexity of the system as scope of the system may expand beyond original plans. • If client is not satisfied with the developed prototype, new prototype should be made, this may lead to be expensive.
- 7. Regards