Rapid Application Development (RAD)

     Rapid Application Development (RAD) is an incremental software development process model that emphasizes an extremely short development cycle.If requirements are well understood and project scope is constrained, the RAD process enables a development team to create a ‘fully functional system’ within very short time periods (eg. 60 to 90 days).

• Business modelling - The information flow in a business system considering its functionality.
• Data Modelling - The information flow defined as part of the business modelling phase is refined into a set of data objects that are needed to support the business
• Process Modelling - The data objects defined in the data modelling phase are transformed to achieve the information flow necessary to implement business functions.
• Application generation - RAD assumes the use of 4GL or visual tools to generate the system using reusable components.
• Testing and turnover - New components must be tested and all interfaces must be fully exercised.

Problems with the RAD model

• RAD requires sufficient human resources to create right number of RAD teams.
• RAD requires developers and customers who are committed to the rapid-fire activities necessary to get a system completed in a much abbreviated time frame.
• If a system cannot be properly modularized, building the components necessary for RAD will be problematic.
• RAD is not applicable when technical risks are high. This occurs when a new application makes heavy use of new technology or when the new software requires a high degree of interoperability with existing computer programs.