Rapid Application Development (RAD) Model

1.   The rapid application development model is type of incremental software process model in which there is extremely short development cycle.

2.   This model is similar to waterfall model which achieves the high speed development using component based construction.

3.   To develop the fully functional system within short time period using this model it is necessary to understand the requirements fully and to have a restricted project scope.

4.   Various phases of RAD model are:

a.   Business modelling – In business modelling, the information flow is modelled into various business functions. These business functions collect following information.

                                          i.    Information that derives the business process.

                                        ii.    The type of information being generated.

                                       iii.    The generator of information

                                        iv.    The information flow.

                                         v.    The processor of information

b.   Data modelling – In this phase the information obtained in business model is classified into data objects. The characteristics of data objects (attributes) are identified. The relationship among various data objects is defined.

c.   Process modelling – In this phase the data objects are transformed into processes. These processes are to extract the information from data objects and are responsible for implementing business functions.

d.   Application generation – For creating software various automation tools can be used. RAD also makes use of reusable components or creates reusable components to have rapid development of software.

e.   Testing and turnover – As RAD uses reusable components the testing efforts are reduced. But if new components are added in software development process then such components need to be tested.

Drawbacks of RAD model

1.    It requires teams or large number of people to work on the scalable projects.

2.    This model requires heavily committed developer and customers.

3.    The projects using RAD model requires heavy resources.

4.    If there is no appropriate modularization then RAD projects fail.

5.    The projects using RAD model find it difficult to adopt new technologies.