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System life cycle (Analysis ((solutions could include:, adapt the current…
System life cycle
Analysis
The analysis phase is where you look at alternative solutions which could be used to solve the problems.
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- adapt the current system. There are bound to be bits that are good with it so perhaps keep those and look at changing the things which aren't working
- buy an 'off-the-shelf' solution. Perhaps use it as it comes or pay to have parts of it adapted to suit your company
Feasibility study
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Performance: No change, system remains outdated. Process becomes increasingly less efficient.
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Benefit: Best parts of the system are kept, whilst the least efficient parts are redesigned to improve performance.
Cost: Moderate, training moderate.
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Cost: High, given that new equipment / software will be required. Training for staff needed.
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Investigation
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- Observing people doing their job
Diagrams
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These show the relationships between the various systems in the company (or even outside if relevant) - how they interact, what depends on what and so on.
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Most systems deal with information in one way or another. What really matters is how the information flows through the system.
People handle information in a specific way - they have a 'process'. For example, an employee makes an expense claim. First of all their manager counter-signs the claim. It then goes to the account manager who authorises payment and so on.
A process diagram will try to show these processes in action.
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Design
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The font style, size and colour are picked
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Development
This phase is where the system starts to be written by the software programmers. They follow the requirements specification from the design stage and start to create the new system.
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A team ensure that the hardware and software required to run the new system are purchased and in place.
A team of testers are assembled in readiness to test the new system. They start to write a test plan which details all of the tests that they will carry out.
Testing
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- The system opens and closes properly
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- Data is saved to the correct place
- When you do something wrong, an error message appears
- Data which isn't allowed will be rejected e.g. if you are not allowed to enter an amount above £1,000 on the system then a value of 1,001 will not be allowed.
Implementation
The system has now been tested and everyone is happy that it is working correctly. It now needs to be installed so that staff can use it. There are three different ways that you can implement (install) a new system:
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Of course, this is the simplest scenario! All the workers are waiting for the fabulous new system to come 'on -line' but as the minutes tick by, a new customer has just ordered a holiday / medical operation / flight / mortgage.
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Answer: You must deal with last minute changes and accept that there may be some upheaval and mistakes made in the short term.
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A popular method compared to the switch off / switch on approach. After all, the customer does not care what your IT system is made up of - they are only (rightly) concerned with their holiday / medical operation / mortgage etc being booked correctly.
And so, a popular method is to allow the old system to run alongside the new one. Then in the quiet period (say overnight) , the new system absorbs all the old system's information. By the next morning, the system is fully loaded and ready to go.
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This can be done by introducing the whole system to just a couple of branches and checking how it works and quickly fixing any bugs that are found. Once things are running smoothly the system will be introduced to the rest of the company.
Or it could be that just parts (modules) of the system are introduced at a time. As they are found to work, further parts are released.
Evaluation
These questions are answered by considering details written down in the original Requirements Specification and comparing it to the performance of the new system.
Maintainence
Once the system has been installed and is up and running, there will be a need to keep maintaining it:
Over time, bugs will be discovered that weren't picked up in the testing. These will need to be fixed.
Staff or developers will identify parts of the system which could be tweaked to work more efficiently.
Larger changes might need to be made to the system. Perhaps extra functionality or maybe changes in working practices or the law might mean that parts of the system have to be altered.
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