software development

• What are the different approaches to software development

  • waterfall life cycle
  • spiral model
  • agile methodologies
  • rapid application development
  • extreme programming
• Describe Waterfall lifecycle

  • each stage is completed one after the other
  • one must be completed before the next one begins
  • stages:
  • analysis
  • design
  • testing
  • evaluation
• Benefits of waterfall model for software development

  • suitable when user requirements are well-understood and clearly specified
  • well-structured and understood, making it easier to plan with clear lines of responsibility
  • large projects can be divided into smaller sub projects, each following their own waterfall
• Criticisms of the waterfall method for software development

  • very rigid
  • extensive documentation required
  • lack of user involvement
  • heavy dependence on accurate requirement specifications
  • challenging when users can't fully articulate needs
  • testing schedules late in the cycle, making it challenging to address defects
  • limited feedback review during development
• Describe the spiral model for software development

  • iterative waterfall method
  • involves creating a prototype following waterfall method and then acting on feedback in evaluation stage and fixing until the user is happy
• describe the benefits of the spiral model for software development

  • suitable for large scale/ high risk projects
  • emphasis on risk management allows for flexible/ adaptive approach to development
• criticisms of the spiral model for software development

  • requires a risk management expert
  • increasing costs
• Describe agile methodologies for software development

  • advocates building prototypes, testing and incorporating feedback quickly
  • emphasises iterative changes
  • emphasises frequent contact with users
• benefits of agile methodologies

  • suitable for small -> medium projects
  • increased customer satisfaction due to frequent contact
• criticism of agile methodologies

  • may lead to scope creep
• describe rapid application development for software development

  • based on prototyping
  • emphasises adaptability over planning
• benefits to rapid application development

  • suited for projects with unclear requirements
  • suitable for smaller projects with smaller development teams which include users
  • continuous feedback
• criticisms of rapid application development

  • sloppiness due to 'try-it-and-see' approach
  • ignores importance of ensuring overall system architecture is correct
  • project can be extended due to user input
• describe extreme programming for software development

  • agile method
  • focuses on code refinement (compared to RAD)
  • frequent releases in short development cycles (shorter than RAD)
  • continuous communication with customer
  • programming done in pairs
• benefits of extreme programming

  • high quality code leads to fewer bugs and less time spent fixing them
  • strong focus on user involvement to meat requirements
• criticisms of extreme programming

  • scope creep
  • high communication/collaboration challenging if team not in same location
  • client must commit to active user involvement throughout project