The Systems Cycle Questions

Describe the analysis and testing stages of life cycle (4 marks)

1 for identification, 1 for expansion / example:

• The analysis stage concludes with a set of requirements the analysis determines what needs to be done.
• Analysis involves questionnaires/interviews/document analysis/observation of current system.
• The finished system is tested against the requirements specification the testing determines whether what has been done works or not.
• Testing is to find bugs/errors using normal/extreme/erroneous data/following a test plan.
• Analysis is the first stage/comes before design.
• Testing comes after implementation/before installation.

Give two comparisons of questions & interviews for investigating (4)

• The course of interviews can change during the process whereas the structure of questionnaires are fixed in advance
• Questionnaires are anonymous  whereas you see and talk to the person being interviewed
• Questionnaires are structured clearly and provide opportunities for short answers whereas an interview provides an opportunity to offer additional information that the analyst may not have considered
• Body language can offer conclusions about answers being given during interviews whereas with questionnaires you do not get to see the person filling them in 

Describe prototyping as a method of software development (2)

• A model is built and evaluated to enable an approved version to be put into production.
• An iterative process of design and evaluation/repeated until an interface is satisfactory.
• A working user interface is created which does not process any data.
• Evolutionary – model is used as basis for development.
• Throwaway – model is redeveloped from scratch in development.

• Normal/correct/valid data, everyday data that is expected /should not generate any error messages on entry.
• Extreme/boundary data, data at the upper/lower boundaries of tolerance.
• Erroneous/incorrect/invalid data, incorrect data outside the boundaries of tolerance or wrong data type / should generate error messages on entry/not be accepted.

• A programming system (used by programmers).
• Used to quickly build working programmes.
• A number of tools to help build GUI’s.
• Reduces development time.
• Can reduce amount of efficient executable code. 
• A software development methodology.
• Involves iterative development.
• Involves the construction of prototypes.
• JAD/Timeboxing.

Describe the difference between Requirement specification and design specification (2)

• Requirements specification is developed by the systems analyst.
• Design specification is developed by the systems designer.
• Requirements specification clearly defines what the system is to do, design specification how this will be achieved. 
• Example: Requirements specification states what is to be stored, design specification gives table structure to storing.

Implementation eg:

• It uses the design specification/output from the design stage and takes it forward/puts it into practice.
• It is when the coding would be created for the required inputs, processing and required outputs.
• It is when off-the-shelf software is customised dependent upon the needs of the client.
• Creates working software that can be tested.

• Placing of finished project into use parallel/phased/pilot/direct strategy used.
• Presents opportunity for staff training using completed and tested software code. 
• Data transfer where data keyed into new system.

• Investigates the current system using investigation methods/ observation/ interview/ document analysis/questionnaires.
• Liaises with staff/management within the organisation to ascertain how the current system works and how it could be improved.
• Writes feasibility study and requirements specification / user requirements. 

identify two items of documentation produced during the documentation stage of the system life cycle and describe the purpose of each

• User manual to provide reference material for staff training to ensure that users can use the system effectively and solve problems. 
• Technical guide so that in the event of maintenance the programmer employed will know how the system was constructed.
• Program/System specifications listing hardware and software required with minimum requirements to run the program.
• Security details including passwords and access rights as staff will change during the life of the system.
• Recovery plan that may include how to retrieve backups in the event of a system failure / disaster.
• Test plans, data and logs so that in the event of future changes to the system the test plan can be re-run to ensure that the same results are produced.

Describe how prototyping can be used to develop an application (4)

• Prototype created.
• Given to client.
• Changes/errors identified.
• Changes implemented.
• Iterative cycle/Given back to client.
• Can be evolutionary/throwaway.

Describe and indentify two other methods that a system analyst could use other then interviews and questionnaires.

• Meetings e.g.  Groups of workers are gathered together questions can be asked directly/ideas expressed/points discussed.
• Document analysis e.g.  Documents from the (current) system are used and the format of input/output is identified.
• Observation e.g. The systems analyst watches/shadows a worker performing their job to record the processes that take place.