ICT A2
Development Methods
Linear Method
This method is known as the linear method because it requires you to finish one stage of the system before moving on to the next stage of the system development. The waterfall methodology is a type of linear method and they are often interchanged.
Advantages
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Offers a simple disciplined approach to the development of the system.
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Ensure that all tasks are dealt with immediately and completely so you do not have to go back to them.
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It reduces costs by helping to discover bugs in the software earlier on rather than spending a lot to correct it down the line.
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Emphasises the need for documentation so that when a staff member leaves a new one can easily pick up from where the last left off.
Disadvantages
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Does not take into account the fact that projects do not follow a sequential approach as you have to go back
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Does not recognise that clients may want a rough version of the system or a prototype which requires you to go over all stages quickly.
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Does not consider that a working version of the system would only be produced late into the development process if the linear method is used.
Examples of Appropriate Use
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Where the project is large, complicated and expensive.
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Where the pressure for immediate implementation does not exist.
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Where the project has clear objectives.
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Where the project requirements are specific and would allow immediate completion.
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Where the project team are inexperienced.
Iterative Method
In this method the stages undergo a cyclic development process in which each stage is tested and evaluated once completed. If the results are unsatisfactory, then the system is improved until it meets the required standard.
Advantages
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It helps the project to improve each time a stage is completed.
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It allows more user and client involvement as they can see what is going on at the end of each stage which then improves the system because it has user involvement all the way through.
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It places high emphasis on prototypes which means less documentation ad more deliverables.
Disadvantages
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Greater user involvement means that users are taken away from their day-to-day activities.
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Increased user involvement would lead to the user wanting increased functionality therefore increasing costs.
Examples of Appropriate Use
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An online system where there is extensive user/client dialogue which allows the user to give constant feedback, which is then acted on.
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Where project objectives are not clear
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Where there is pressure for immediate implementation
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Where project team members use their expertise to cut out steps that are not needed.