Explain the protoyping model of software development

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 Prototyping Model

Prototyping is the iterative process of system development which is more appropriate for developing a new system where there is no clear idea of requirements, inputs, and output. Using prototyping, programmers can build an early version of systems. These systems are then continuously modified until the users are satisfied. Prototyping is especially helpful in situations where there will no heavy user interaction with the system, where the needed output is uncertain, and in some decision support applications where the logic is hard to determine in advance. The developer interviews the user and designs an initial system using a database management system. The user works with the prototype and suggests changes. The process repeats until the user or developer is satisfied.

 



The figure shows the steps involved in developing the type of prototype. There are 4 steps and are as follows:-

Identify the user need  
              The system analyst interviews the user to obtain an idea of what is required for the system.

Develop a prototype

The system analyst, working with other information specialists, uses one or more prototyping tools to develop a prototype.

Determine if Prototype is acceptable

 The analyst educates the user in prototype use and provides opportunities from becoming familiar with the system The user advises the analyst whether the prototype is satisfactory. If so then the next step, that is step 4 is taken else, the prototype is revised by repeating steps1,2 and 3 with a better understanding of the user's need.

Use the Prototype

The prototype becomes the operational system. This approach is possible only when the prototyping tools enable the prototype to contain all the essential elements of the new system.


Advantages of Prototype Model

  • Reduce the risk of incorrect user requirement
  • Good where requirement is changing/uncommitted
  • Regular visible process aids management
  • Support early product marketing
  • Reduce Maintenance cost.
  • Errors can be detected much earlier as the system is made side by side.


Disadvantages of Prototype Model

  • An unstable/badly implemented prototype often becomes the final product.
  • Require extensive customer collaboration
  • Costs customer money
  • Needs committed customer
  • Difficult to finish if customer withdraw
  • Maybe too customer-specific, no broad market
  • Difficult to know how long the project will last.
  • Easy to fall back into the code and fix without proper requirement analysis, design, customer evaluation, and feedback.
  • Prototyping tools are expensive.
  • Special tools & techniques are required to build a prototype.
  • It is a time-consuming process.

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