11. System Analysis Flashcards
What is a feasibility study
A feasibility study checks if the project is possible and worth doing, considering its scope. If chosen to proceed there must be confidence on both sides ensuring the project can be delivered on time and within budget.
What is Economic Feasibility?
A project has a specific budget which must costs of software licenses, hardware and human wages (human costs are most variable).
What is time feasibility?
Late projects result in going over budget because of the cost of developers wages so its important they are delivered on time, as the developing company will make a negative impression.
What is Technical Feasibility?
Considers if the project can be done with the resources available as some things are not possible or feasible with current technology. For example accurate speech recognition is not reliable nor is facial recognition in dark environments.
What is Political Feasibility?
Projects can sometimes have aspects that are politically sensitive or go against the beliefs of certain groups of people. Systems such as NHS, tax credits, Olympic computer systems and animal testing come under the direct scrutiny of the general public and media.
What is Legal Feasibility?
Legal Feasibility helps decide whether the project will be able to comply with all laws that may affect it in countries where it has be released. File sharing software (for example) although legal in essence has fallen foul of the law,
What is Analysis
Analysis uses various fact-finding methods to determine precisely what the system will involve. These include:
- Observation
+ Picks up parts of the system that are not immediately obvious to the customer - Some people may feel threatened while being watched
- Some subtle system parts may not appear during observation.
Questionnaire
+ can be given to a large number of people
+ can get a large number of different peoples opinion
- hard to create and design
- not all will be completed
What is Design?
Design shapes how a new system looks, stores, and processes data from its requirements. The design includes a number of areas:
- hardware and software choices
- data structure design
- input + output design
What is direct changeover?
Replaces old system completely in one go
+ Quick
+ Can be cheap if it works as there is no long term running costs
- Employees could be resistant to change
- Employees could need training reducing productive output
What is Phased Changeover?
The new system is gradually brought in while the old system is still used.
+ employees can choose which system they prefer minimising resistant behaviour
- large complex change can take a long time
What is pilot changeover?
The new system is introduced to one part of the company a time.
+ Fixing problems is easy as it has minimal impact on the company, given initial limited usage.
+ staff can learn the system then train other staff reducing training costs
- high costs as two systems are running simultaneously
- limited scope
What is parallel changeover?
Both systems are ran at the same time
+ employees can choose which system they prefer
+ safe as you have the old systems as back up
- expensive to run two systems simultaneously
- When preferred older systems reach end-of-life, employees may become disgruntled, causing issues.
What is alpha testing?
Alpha Testing is conducted by the developers typically module by module.
What is Beta Testing
Beta testing is conducted by prospective end users who use the system as they would use the end product.
What is Adaptive Maintenance
In adaptive maintenance the development company fixes bugs and also adds extra functionality to the system.
