System Development Life Cycle (SDLC) Flashcards
Describe three system maintenance methods including examples for each
Corrective maintenance: ‘bugs’ which may have not been identified during testing may need correcting
- eg. A piece of SW may crash when used with a particular item of hardware
Perfective maintenance: improving the performance of the SW
- eg. Developing online tutorials and more help screens to help new staff learn the SW
Adaptive maintenance: SW may need to be changed due to the changing needs of the business environment
- changes to values such as he percentage rate of VAT will result in changes to the software
Describe and evaluate two changeover strategies the analyst could use
Direct changeover: stop using the old system one day and start using the new system the next day
+Requires fewer resources (people, money, equipment) and is simple, provided nothing goes wrong
- Element of risk because if the system fails it can be disastrous for the business
Parallel changeover: Old ICT system is run alongside the new ICT system for a period of time until all the people involved with the new system are happy it is working correctly
+ Used to minimise the risk in introducing a new ICT system
- Lots of unnecessary work as the work is being done twice and is therefore a waste of people’s time
Name four reasons as to why users may become dissatisfied with the their ICT system
The full range of user requirement has not been met , so the system does not live up to the users expectations
Failure to supply users with the information they require
Too much time is spent on updating the new system
Change in business needs means the system cannot deal with new demands placed on it
Describe three different ways a systems analyst can gather information about the existing system
Interviews with managers about the current system:
- interviews with managers normally reveal how the departments works now
- any current problems/issues raised
Observation of how the current system operates:
- any time delays or problems with the current system
- Can be time consuming and span several weeks before you can see everything
Questionnaires which are given out to managers / users to gather information for the company:
- state how you want the new system to work and what information they want
- Economical to reproduce and distribute
Describe the purpose of the feasibility report and five things that it should include
Feasibility report: is the initial investigation to look at the likelihood of being able to create a new system with stated aims and objectives at reasonable cost. The document is used by senior managers to assess whether it is worth continuing with the project
Should include:
- user requirements should be identified
- identification of problems with the current system
- potential improvements/benefits of the new system
- conclusions is it worth proceeding
- details of existing hardware/ software: do they have the equipment to implement?
Describe four features or processes which should be considered when designing a new computer system
Design of input methods such as design of forms,
(data capture/switchboard) used to input data
Design of output - reports/specialist documents such as invoices, payslips etc.
Design of networks and transmission issues - topology, type of cable, protocols etc
Security processes and procedures - eg. Registering with the Information Commissioner, where the data is stored, access levels and design of backup procedures etc.
Describe using example four maintence issues that could arise after a new ICT system has not been fully tested
Identification of errors - ‘bugs’ which may have not been identified during testing may need correcting
Changes in legislation - eg. changes to values such as he percentage rate of VAT will result in changes to the software
Changes in the business environment - eg. If company was to expand and grow the ICT system may not be equipped to deal with the demand
Security issues - eg. The system may be continuously targeted by hackers or viruses
What is a Systems Development Life Cycle (SDLC)
The standard method that software developers follow when making a new computer system
A series of tasks, completed in sequence, which allows a software solution to be developed
