Explain the main concepts of the Waterfall method:
- Each step completed one by one
- Each step creates output for next step
- Possible to return to previous step, but you will have to go back down through each stage.
What stage(s) of the Waterfall method are customers involved in?
Involved in the Analysis (beginning) but have little input until the Evaluation (end).
What is the origin of the waterfall method and how well is it used nowadays?
Taken from the manufacturing industry but ow superseded by more effective models.
Explain the main concepts of the Spiral method:
Uses the same structured steps of waterfall method but focuses on an overall iterative (repeating method) of development.
What happens at the start of the Spiral method?
Requirements are defined and developers work towards an initial prototype.
What does each ‘loop’ of the spiral process produce?
Each ‘loop’ generates a refined prototype.
What types of project is the Spiral method used for?
Large scale projects that may take a long time to deliver.
What are the stages of the Spiral development? Provide a definition for each one.
- Analysis: Analyse the requirements for next prototype.
- Design: Design the next version/prototype.
- Implement: Code/Test new prototype.
- Evaluate: Evaluate new prototype, plan next one.
Explain the main concepts of the Agile Development method:
- Focuses on iterative development.
- Feedback taken from user during development process.
- Software Developers only make an initial model during the start of each iteration.
- Development stages may not be completed linearly.
Why does Agile Development focus on iterative development?
Recognises that requirements may change during development.
What does Agile modelling depend on?
- Simple models developed
- Rapid user feedback
- Ability to make incremental changes
- Understanding user requirements may change.
What is Extreme Programming?
XP is a form of Agile Development intended to improve software quality and responsiveness to changing user requirements.
Explain the main concepts of the Extreme Programming method:
- Frequent releases are made in short development cycles.
- Customer has heavy involvement.
What often happens as a development method with Extreme Programming and what is this called?
An ‘Analyser’ (Overseer) and ‘driver’ (coder) develop the software, switching roles often. This is called Paired Programming.
What is the downside and advantage to Paired Programming?
It is expensive but allegedly produces higher quality results.
Explain the main concepts of the Rapid Application Development method:
- Formal requirement replaced by focus groups/workshops.
- Prototypes used to continually refine model in response to model feedback.
- Strict time limits employed for development of each part.
- Reusing software components that have been reused elsewhere.
What is the advantage of RAD and what does it stop?
RAD allows a major product to be developed very quickly over a short time period. It stops large projects being canceled at a late stage due to changes in user requirements.
Where is the Waterfall method used?
Suitable for very small projects that need careful supervision, eg student/trainee projects.
What is bad about the Waterfall method.
There is a lack of user involvement.
What is good about the Spiral and Agile development methods?
- Acknowledges users can’t initially specify all requirements (may not realise what is possible).
- Produces prototypes which are easier to examine and refine.
What is the XP and RAD methods suitable for?
Large projects with a danger of getting ‘bogged down’ or side tracked by suggested improvements.
