Software Development - Stages

Question 1

Explain the main concepts of the Waterfall method:

Answer 1

• 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.

Question 2

What stage(s) of the Waterfall method are customers involved in?

Answer 2

Involved in the Analysis (beginning) but have little input until the Evaluation (end).

Question 3

What is the origin of the waterfall method and how well is it used nowadays?

Answer 3

Taken from the manufacturing industry but ow superseded by more effective models.

Question 4

Explain the main concepts of the Spiral method:

Answer 4

Uses the same structured steps of waterfall method but focuses on an overall iterative (repeating method) of development.

Question 5

What happens at the start of the Spiral method?

Answer 5

Requirements are defined and developers work towards an initial prototype.

Question 6

What does each ‘loop’ of the spiral process produce?

Answer 6

Each ‘loop’ generates a refined prototype.

Question 7

What types of project is the Spiral method used for?

Answer 7

Large scale projects that may take a long time to deliver.

Question 8

What are the stages of the Spiral development? Provide a definition for each one.

Answer 8

• 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.

Question 9

Explain the main concepts of the Agile Development method:

Answer 9

• 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.

Question 10

Why does Agile Development focus on iterative development?

Answer 10

Recognises that requirements may change during development.

Question 11

What does Agile modelling depend on?

Answer 11

• Simple models developed
• Rapid user feedback
• Ability to make incremental changes
• Understanding user requirements may change.

Question 12

What is Extreme Programming?

Answer 12

XP is a form of Agile Development intended to improve software quality and responsiveness to changing user requirements.

Question 13

Explain the main concepts of the Extreme Programming method:

Answer 13

• Frequent releases are made in short development cycles.

- Customer has heavy involvement.

Question 14

What often happens as a development method with Extreme Programming and what is this called?

Answer 14

An ‘Analyser’ (Overseer) and ‘driver’ (coder) develop the software, switching roles often. This is called Paired Programming.

Question 15

What is the downside and advantage to Paired Programming?

Answer 15

It is expensive but allegedly produces higher quality results.

Question 16

Explain the main concepts of the Rapid Application Development method:

Answer 16

• 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.

Question 17

What is the advantage of RAD and what does it stop?

Answer 17

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.

Question 18

Where is the Waterfall method used?

Answer 18

Suitable for very small projects that need careful supervision, eg student/trainee projects.

Question 19

What is bad about the Waterfall method.

Answer 19

There is a lack of user involvement.

Question 20

What is good about the Spiral and Agile development methods?

Answer 20

• Acknowledges users can’t initially specify all requirements (may not realise what is possible).
• Produces prototypes which are easier to examine and refine.

Question 21

What is the XP and RAD methods suitable for?

Answer 21

Large projects with a danger of getting ‘bogged down’ or side tracked by suggested improvements.