SDLC : Phases: SDLC : Phases
Phases of SDLC: Phases of SDLC Systems analysis, requirements definition: Refines project goals into defined functions and operation of the intended application. Analyzes end-user information needs. Systems design: Describes desired features and operations in detail, including screen layouts, business rules, process diagrams, pseudo code and other documentation. Implementation (Development): The real code is written here. Integration and testing: Brings all the pieces together into a special testing environment, then checks for errors, bugs and interoperability. Acceptance, installation, deployment: The final stage of initial development, where the software is put into production and runs actual business. Maintenance: What happens during the rest of the software's life: changes, correction, additions, moves to a different computing platform and more.
Slide 4: Waterfall Model This is the most common and classic of life cycle models. In a waterfall model, each phase must be completed in its entirety before the next phase can begin. At the end of each phase, a review takes place to determine if the project is on the right path and whether or not to continue or discard the project. Unlike in the general model, phases do not overlap in a waterfall model.
Slide 5: Advantages * Simple and easy to use. * Easy to manage due to the rigidity of the model – each phase has specific deliverables and a review process. * Phases are processed and completed one at a time. * Works well for smaller projects where requirements are very well understood. Disadvantages * Adjusting scope during the life cycle can kill a project * No working software is produced until late during the life cycle. * High amounts of risk and uncertainty. * Poor model for complex and object-oriented projects. * Poor model for long and ongoing projects. * Poor model where requirements are at a moderate to high risk of changing.
Slide 6: Spiral model - The spiral model emphasizes the need to go back and reiterate earlier stages a number of times as the project progresses. It's actually a series of short waterfall cycles, each producing an early prototype representing a part of the entire project
Slide 7: Iterative models - by definition have an iterative component to the systems development. It allows the developer to take a small segment of the application and develop it in a fashion that, at each recursion, the application is improved.
Slide 8: SPIRAL: Advantages * High amount of risk analysis * Good for large and mission-critical projects. * Software is produced early in the software life cycle Disadvantages * Can be a costly model to use. * Risk analysis requires highly specific expertise. * Project’s success is highly dependent on the risk analysis phase. * Doesn’t work well for smaller projects ITERATIVE: Advantages *Useful for building small to medium sized systems and for building systems of high reliability. * Useful for testing the system within the development in starting Disadvantages *Iterations may never end *Cost estimation high THANK YOU