PROTOTYPING.
Prototyping is the repaid development and testing of working models, or prototypes, of new applications in an interactive, iterative process can be used by both systems analysts and end users. Prototyping makes the development process faster and easier for systems analysts, especially for projects where end user requirements are hard to define. Thus, prototyping is sometimes called rapid application design (RAD)
Prototyping has also opened up the application development process to end users because it simplifies and accelerates systems design. These developments are changing the roles of end users and information systems specifications in systems development.
THE PROTOTYPING PROCESS.
Prototyping can be used for both large and small applications. Typically, large systems still require using the traditional systems development approach, but parts of such systems can frequently by prototyped. A [prototype of a business application needed by an end user is developed quickly using a variety of application development packages. The prototype system is then repeatedly refined until it is acceptable to an end user
o Investigation/Analysis: End Users identify their information needs and assess the feasibility of several alternative information system solutions
o Analysis/Design: End users and/or systems analysts use application development packages to interactively design and test prototypes of information system components that meet end user information needs.
o Design/Implementation: The information system prototypes are tested, evaluated and modified repeatedly until need users find them acceptable.
o Implementation/Maintenance: The acceptable information system can be modified easily since most system documentations stores on disk.
Prototyping is an iterative, interface process that combines steps of the traditional systems development cycle. End users with sufficient experience with application development packages can be prototyping themselves. Alternatively, an end user can work with a systems analyst to develop a prototype system in a series of interactive sessions. For example, they could be develop, test and refine prototypes of management reports or data entry screens.
The Prototype is usually modified several times until the end user finds it acceptable. Any program modules that are not generated by the application development software can then be codes by programmers using conventional programming languages. The final version of the application system is then turned over to the end user for operational use.
* Team. A few end users and IS
developers form a team to develop a business application.
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* Schematic. The initial
prototype schematic design is developed
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* Prototype. The schematic is
converted into a simple point-and-click prototype using prototyping tools.
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* Presentation. A few screens
and routine/linkages are presented to users.
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* Feedback. After the team gets
feedback from users, the prototype is reiterated.
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* Reiteration. Further
presentations and reiterations are made.
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* Consultation. Consultations
are held with central IT developers/consultants to identify potential
improvements and conformance to existing standards of the organization.
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* Completion. The prototype is
converted into a finished application.
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* Acceptance. Users review and
sign of on their acceptance of the new system.
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* Installation. The new
application software is installed on network servers.
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Once a new information system has been designed, it must be implemented. Figure 3.27 illustrates that the systems implementation stage involves hardware and software acquisition, software development, testing of programme and procedures, development of documentation, and a variety of installation activities. It also involves the education and training of end users and specialists who will operate a new system.
