This article explain about rapid application development as one alternative software development method and how its work.
Husna Mustika Sari
Rapid Application Development (RAD) is one method of developing an information system with a relatively short time. For the development of a normal information system takes at least 180 days, but by using RAD method a system can be completed only within 30-90 days.
The main purpose of all system development methods is to provide a system that can meet the expectations of the users, but often in the development of a system does not involve the users of the system directly, so this causes the information system made far from the expectations of users who can result in such a system though acceptable but users are refuse to use it.
When RAD is implemented, users can become part of the overall system development process by acting as decision makers at every stage of development. RAD can generate a system quickly because the system developed can meet the desires of the users so as to reduce the time for re-development after the implementation phase.
The weaknesses found in conventional methods are as follows:
Weakness of conventional methods
- There is a long time limit from the beginning of the system creation until the consumer can use the system.
- If the process of developing a system takes a long time then the needs of consumers on the system will experience changes in line with changes in business processes undertaken by consumers.
- The developed system will have no benefit if it has not been completely resolved.
The reason why to choose RAD methodsIn choosing the RAD method should consider the following reasons:
- When using RAD just to save on development costs system. Requires a team that understands well about cost management. If not, then the cost will be larger.
- When using RAD just to save some development time system. Requires a team that understands timely management. If not, then the time required will be longer.
- To obtain an acceptable design by consumers and can be developed easily.
- To provide restrictions on a system so as not to change.
- To save time, and if possible save cost and produce a quality product.
Schedule vs economics vs. quality productsThere are several things that need to be considered in developing a system using RAD method based on schedule, economy and product quality such as development model, negotiation, and objectives.
Development ModelAt the time of developing a system must be faced with 3 choices of models that is:
Efficient Development (development model that prioritizes the schedule, economy and product quality in a balanced manner).
- Schedule: faster than average
- Economy: the cost is cheaper than the average
- Product: better than average quality
Sensible RAD (development model that prioritizes the schedule compared to economy and product quality).
- Schedule is faster than average
- Economy is the cost slightly cheaper than average
- The product is slightly better than average quality
All-out RAD (development model that prioritizes the schedule at the expense of economy and product quality).
- Schedule is fastest
- Economy cost is more expensive than average
- The product quality is more lowest than average
- To produce a system that suits the needs and wants of the user it is necessary to conduct a negotiation and not just prioritize the schedule.
- RAD can be done quite successfully if the consumer is able to negotiate to determine the economy or quality of a system.
- RAD can achieve better success if consumers are able to negotiate to determine the economy and quality of a system.
- However, the thing to note is that the definition of quality negotiations does not mean that consumers can accept more of more mistakes, but what is meant by negotiations is that the products received have a disadvantage either on the use, completeness of facilities or less efficient.
- but what is meant by negotiations is that receive the disadvantages of products either on the use, completeness of facilities or efficient
By using RAD then there is one or more of the following objectives that can not be achieved simultaneously:
- Possibility of a small error, because the developer has no right to change the components used in developing a system.
- The highest level of customer satisfaction, because the secondary needs of consumers must be sacrificed so that a system can be completed on schedule.
- Development costs are the cheapest, because by using existing components can cause a greater cost when compared to developing its own components.
Phases on RADThe RAD method has 3 main stages as shown in Figure 1.
Requirement PlanningAt this stage, users and analysts do some sort of meeting to do identify the purpose of the application or system and identify the information needs to achieve the objectives. At this stage the most important thing is the involvement of both parties, not just the approval of the proposals that have been made. The rest, user involvement is not just from one level in an organization, but some level of organization so that the information needed for each user can be met well. In addition, it can also coordinate with the Chief Information Office (CIO) or part of strategic planners primarily to develop a Web-based E-commerce application to get more detailed information about the goals of an organization. This kind of meeting is often called Joint Aplication Development.
At this stage, the design user and analyst to do the design process and make improvements if there is still a mismatch between them. For this stage the activation of the user involved is crucial to achieve the goal, because the user can directly comment if there is a mismatch on the design. Usually, users and analysts come together and sit on a circular table where each person can see each other without a hitch.
Whenever possible, each user is assigned one computer connected to each other, so that each can see the design created and comment directly. This is often called Group Decision Support System (GDSS). In some cases, this GDSS is an ideal step, because users and analysts can approve the design that is made to be followed by the programmer in making the prototype of the app in question by instantly displaying to the user the results quickly.
It this stage of the design takes a few days, but it can take longer, depending on the size of the system created. At that time interval, the user can give response to the system that has been developed for further improvement. Thus the process of developing a system takes a fast time.
ImplementationAfter the design of the system to be made has been approved by both the user and analyst, then at this stage the programmer develops the design into a program. After the program is completed either partly or as a whole, then do the process of testing the program whether there is an error or not before applied to an organization. At this time the user can respond to the system that has been made and approval of the system.
The most important thing is that the involvement of the user is needed so that the system developed can give satisfaction to the user, and in addition, the old system does not need to run in parallel with the new system.
Overall stagesBased on the stages mentioned above, the main process of developing a system using RAD method is as follows:
- Developers create prototypes based on predefined needs
- Designers make an assessment of the prototype
- Users tested the prototype and provided input on the underlying needs.
- Users and developers conduct meetings to provide assessment of the products together, adjust the needs and provide comments if necessary changes.
- All the needs of the system and the changes that occur are "timeboxed" with two possibilities: The first is changes that can not be accommodated as planned should be eliminated. And the second, if necessary, secondary needs are eliminated.
Condition affecting RADAt the time of using RAD methods need to consider the conditions that can support and inhibit the success of a system.
Supporting ConditionsSome conditions that can support the success of RAD are as the following:
- System running alone (standalone).
- Performance of the system is not the most important factor.
- Distribution of narrow products.
- Limited scope.
- Reliability of the system is not the most important factor.
- Requires technology that is not too new (more than 1 year).
- System can be broken down into smaller parts.
Some conditions that may hinder the success of RAD are as follows:
- The system must be able to run simultaneously with the old system.
- Supporting components are very rare to obtain.
- Optimal performance is the most important factor.
- Distribution of products that are wide.
- Wide scope.
- When used to create the Operating System, which requires a reliable system.
- The system can not be broken down into smaller parts.
ADVANTAGES AND DISADVANTAGES OF RADIn using RAD there are some things to note especially related to the advantages and disadvantages.
Advantages of RAD
- Some of the advantages of using the RAD method are as follows:
- Buying a new system make it possible to save more money instead of developing it yourself.
- The delivery process becomes easier, this is because the process of making more use of script deductions.
- Easy to observe, because it uses a prototype model, so users better understand the system developed.
- More flexible, because the developer can do the redesign process at the same time.
- Can reduce the writing of complex code because it uses wizard.
- Increased user engagement as it is part of the team as a whole.
- Able to minimize errors using the help tools (CASE tools).
- Accelerate overall system development time as it tends to ignore quality.
- Display more standard and comfortable with the help of supporting software.
Disadvantages of RADSome of the disadvantages of using the RAD method are as follows:
- By making a purchase may not be able to save costs compared with developing their own.
- Requires a separate cost to buy supporting equipment such as software and hardware.
- Difficulty in making measurements of process progress.
- Less efficient because when doing the coding by hand can be more efficient.
- The accuracy becomes reduced because it does not use a formal method of coding.
- More errors occur when only prioritizing speed compared to cost and quality.
- Many facilities are reduced due to the limited time available.
- The system is difficult to apply elsewhere.
- Unnecessary facilities sometimes need to be included, as they use ready-made components, so this makes costs increasing as the price of the more complete components becomes more expensive.
ConclusionBased on the above discussion, then in using the RAD method can be summed up as follows:
- The use of RAD should be used appropriately, because otherwise it will cause losses such as increasingly bloated costs and longer time.
- The use of RAD methods should be used with regard to time and cost aspects in a balanced way, not to be prioritized one by one.
- As an alternative to the SDLC RAD can be used as a reference to develop an information system that is superior in terms of speed, accuracy and lower costs.
- By using RAD, the user's involvement becomes increasingly which can ultimately increase user satisfaction with the developed system.
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