Development Methodologies Flashcards
Phases to create a solution for a problem in a computer system.
Software Development Life Cycle (SDLC)
Software development methodology
how the phases are sorted
Stages of SDLC
• Feasibility
• Requirements
• Analysis/Design
• Implementation
• Testing
• Deployment
• Evaluation
• Maintenance
Feasibility
Is the problem solvable?
Deployment
Installing into target environment
Waterfall Methodology
• Cascading effect from one phase to another.
• Each stage is well defined start + end - identifiable deliveries.
Rapid Application Development (RAD)
• Producing successive prototypes until a final version.
• Iteration
• Following the initial approval of a feasible program, increasingly refined prototypes are made with reduced functionality.
• Design + code + test + evaluate with end user.
Spiral methodology
• Risk-driven
• Guide + other elements from methodologies can be adopted
• Process model generator
Agile Methodology
• Group of methodologies
• Focus on the idea that requirements shift during development.
• Iterative way
• Series of iteration called SPRINTS
Sprints
Short time-boxed periods when a team has focused goals to complete a set amount of work.
- no longer than one to four weeks
Extreme Programming
•agile framework
•encourages small iterative software releases
Benefits to the Waterfall methodology
• Simplicity makes it easy to manage
• Everyone on the project is very clear on their responsibilities at each stage
• Clear deliverables
• Easy to see if a project is running to schedule
Disadvantages to the Waterfall methodology
• Carries a lot of risk
• The user doesn’t get to see the product for the first time until the end
• Misunderstanding requirements can lead to a project that is not easy to fix
• Requirements must be very well understood, so it’s not suitable for complex projects
What types of projects is the Waterfall methodology suitable for?
• Ease of management can make it suitable for large-scale development projects, assuming they are well-understood and carry little risk
Benefits to Rapid Application Development (RAD)
• Requirements don’t need to be entirely clear from the start
• Focus groups involving the user can be used to gather requirements without the need for full formal requirements document upfront
• Continuous feedback from the client means the solution is likely to have excellent usability
Disadvantages to RAD
• Focus on usability rather than how the product works - not suited for projects where code efficiency is very important
• Regular contact with client must be maintained at all times
• Scales poorly for large projects with big teams
What types of projects is the RAD methodology suitable for?
Initial requirements are not fully understood, iterative nature prevents development from becoming side-tracked
Spiral benefits
• Risk management is at the heart of this model
• Excellent for projects that contain a high level of risk
Disadvantages to RAD
• Complex nature of risk analysis increases costs - risk management is a highly specialised skill
• If risk analysis is done badly, the project suffers
What type of projects is the spiral methodology suited to?
Large-scale problems and those that involve a high degree of risk, especially where the user doesn’t fully understand their requirements upfront
benefits to agile and extreme programming
• emphasises programming - quality of end code very high
• core principles and processes promote respect and collaboration, very productive team
disadvantages to agile and extreme programming
• Requires a team of programmers working in close collaboration - unlikely to work if team widely distributed geographically
• Client must be able to commit to gave a full-time representative working with the development team
• Paired programming costly
What type of projects are suited for agile and extreme programming?
Projects that emphasise on the quality of finished code
