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Rapid Application Development |
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This technique emphasizes extensive user involvement in the rapid and evolutionary construction of working prototypes of a system to accelerate the system development process. RAD is sometimes referred to the “spiral approach” because the nature of the technique involves repeatedly spiraling through the phases to construct a system with various levels of completeness and complexity.
The concept of RAD are:
- To more actively involve system users in the analysis, design and construction activities
- To organize systems development into a series of focused, intense workshops jointly involving system owners, users, analysts, designers and builders
- To accelerate the requirements analysis and design phases through an iterative construction approach
- To reduce the amount of time until the users begin to see a working system
- To use prototypes to their fullest potential
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Often a timebox is used to accelerate the RAD process. A timebox is a non-extendable period of time, by which a candidate system must be placed into operation for full system wide exposure. Some system owners believe that management and user enthusiasm for a project can be enhanced and sustained because a working version of the system is implemented on a regular basis.
The benefits of RAD are:
- It is useful for projects in which user requirements are uncertain or imprecise
- It encourages active user and management participation. This increases end-user enthusiasm for the project
- Projects have higher visibility and support because of the extensive user involvement throughout the process
- Users and management see working, software-based solutions more rapidly than in Model-Driven Development
- Errors and omissions tend to be detected earlier in prototypes than in system models
- Testing and Training is a natural by-product of the underlying prototyping approach
- The iterative approach is more “natural” fit because change is an expected factor during development
- It reduces risk because you test the technical solution iteratively instead of making a wholesale commitment to any solution
Rapid Application Development main disadvantages are that some believe that it encourages the “code, implement and repair” mentality and practices. It may increase the overall lifetime costs in operation, support and maintenance. Due to the decrease in time for testing prototypes, the solution can easily resolve the wrong problem or create multiple new problems. If quality is your main issue, RAD is not your choice.
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