Systems Analysis & Design

1. Systems Analysis & Design Rapid Application Design (RAD)

2. What is Rapid Application Development? (RAD) • Rapid Application Development is non-agile processes developed such as the Waterfall model • RAD was form in the 1970’s. • Some of the problems identify with previous methodologies was that applications took so long to build that requirements had changed before the system was complete, often resulting in unusable systems.

3. DEFINITION a software development process that allows usable systems to be built in as little as 60-90 days, often with some compromises • PRINCIPLES BEHIND THE DEFINITION • In certain situations, a usable 80% solution can be produced in 20% of the time that would have been required to produce a total solution. • In certain situations, the business requirements for a system can be fully satisfied even if some of its operational requirements are not satisfied. • In certain situations, the acceptability of a system can be assessed against the agreed minimum useful set of requirements rather than all requirements.

4. PROBLEMS ADDRESSED BY RAD With conventional methods, there is a long delay before the customer gets to see any results. With conventional methods, development can take so long that the customer's business has fundamentally changed by the time the system is ready for use. With conventional methods, there is nothing until 100% of the process is finished, then 100% of the software is delivered.

5. WHY USE RAD? BAD REASONS FOR USING RAD • to prevent cost overruns(RAD needs a team already disciplined in cost management) • to prevent runaway schedules (RAD needs a team already disciplined in time management) GOOD REASONS FOR USING RAD • to converge early toward a design acceptable to the customer and feasible for the developers • to limit a project's exposure to the forces of change • to save development time, possibly at the expense of economy or product quality