25-08-2017, 09:32 PM
Software Life-Cycle Models
SDLC(team3).ppt (Size: 1.62 MB / Downloads: 31)
Software Development in Practice
In the real world, software development is totally different
Software professionals make mistakes
The client’s requirements change while the software product is being developed
A software product is a model of the real world, and the real world is continually changing.
Waterfall Life-Cycle Model
No phase is complete until the documentation for that phase has been completed and the products of that phase have been approved by the software quality assurance (SQA) group.
If the products of an earlier phase have to be changed as a consequence of following a feedback loop, that earlier phase is deemed to be complete only when the documentation for the phase has been modified and the modifications have been checked by the SQA group.
Agile Model
Agile software development is a group of software development methods based on iterative and incremental development
It promotes adaptive planning and encourages rapid and flexible response to change.
Spiral Life-Cycle Model
Precede each phase by
Alternatives
Risk analysis
Follow each phase by
Evaluation
Planning of the next phase
Radial dimension: cumulative costs to date
Angular dimension: progress through the spiral.
Spiral Life-Cycle Model
Minimize risk via the use of prototypes and other means.
Two types of risk:
Analyzable Risk: Time and cost
Un-analyzable Risk:
Personnel turnover
Evaluate the delivery promises of a hardware supplier
Comparison of Life-Cycle Models
Different life-cycle models have been presented
Each with its own strengths and weaknesses
Criteria for deciding on a model include:
The organization
Its management
The skills of the employees
The nature of the product
Best suggestion
“Mix-and-match” life-cycle model