With a neat diagram explain Prescriptive, Waterfall and Spiral model

With a neat diagram explain Prescriptive, Waterfall and Spiral model

Prescriptive Process Models are detailed methodologies that outline specific steps, activities, and tasks for software development.

They are designed to bring order to the software development process by defining a clear, predictable workflow.

The goal is to guide the software team through a structured approach to ensure consistency and control.

Examples of Prescriptive Process Models:

1. Waterfall Model:
   • A linear and sequential approach where each phase (requirements, design, implementation, testing, maintenance) must be completed before moving to the next.
2. V-Model:
   • An extension of the Waterfall Model, emphasizing verification and validation. Each development phase is matched with a corresponding testing phase.

Waterfall Model

The Waterfall Model is one of the earliest and most straightforward software development methodologies. It’s called “waterfall” because the process is visualized as flowing downwards through distinct phases, similar to a waterfall. Here’s a breakdown of how it works:

Stages of the Waterfall Model:

1. Communication:
   • Project Initiation: Defining the project’s scope, objectives, and stakeholders.
   • Requirements Gathering: Collecting and documenting the software’s functional and non-functional requirements.
2. Planning:
   • Estimating: Determining the project’s budget, resources, and timeline.
   • Scheduling: Creating a detailed project plan with milestones and deliverables.
   • Tracking: Monitoring project progress against the plan.
3. Modeling:
   • Analysis: Analyzing the software’s requirements and creating a system design.
   • Design: Developing the software’s architecture, user interface, and database design.
4. Construction:
   • Code: Writing the software code based on the design.
   • Test: Verifying the software’s functionality and performance through testing.
5. Deployment:
   • Delivery: Delivering the completed software to the customer.
   • Support: Providing ongoing support and maintenance.
   • Feedback: Gathering feedback from users to inform future improvements.

Waterfall Model Example: Developing a Simple Website:

Project: A Small Business Website:-

Communication:

• The business owner outlines the website’s purpose (e.g., showcasing products, providing contact information).
• The development team gathers detailed requirements, such as desired pages, content, and design preferences.

Planning:

• The project manager estimates the development time, cost, and resources needed.
• A project schedule is created with specific milestones and deadlines.

Modeling:

• The web designer creates wireframes and mockups for the website’s layout and appearance.
• The development team designs the website’s structure and database (if applicable).

Construction:

• The developers write the HTML, CSS, and JavaScript code for the website.
• The website undergoes thorough testing to identify and fix bugs.

Deployment:

• The completed website is uploaded to a web server.
• The website is launched and made accessible to the public.
• Ongoing maintenance and updates are planned.

Spiral Model

The Spiral Model is a software development methodology that combines the iterative approach of prototyping with the structured approach of the waterfall model. It emphasizes iterative development and risk management, making it particularly useful for complex and large-scale projects.

Stages of the Spiral Model:

The image depicts the four main stages of the Spiral Model:

1. Communication:
   • Gathering requirements and feedback from stakeholders.
   • Communicating project progress and updates.
2. Planning:
   • Estimation: Defining the project scope, budget, and timeline.
   • Scheduling: Creating a detailed project plan with milestones and deliverables.
   • Risk Analysis: Identifying potential risks and developing strategies to mitigate them.
3. Modeling:
   • Analysis: Defining the system’s requirements and specifications.
   • Design: Creating the software architecture and design.
4. Construction:
   • Code: Writing the actual software code.
   • Test: Verifying the code’s functionality and performance.
5. Deployment:
   • Delivery: Delivering the software to the customer.
   • Feedback: Gathering feedback from users to inform future iterations.

Spiral Model Example:

Developing a Mobile Game:-

Cycle 1: Core Gameplay

• Planning: Define basic game concept (e.g., endless runner), target audience (casual gamers), and platform (iOS and Android).
• Risk Analysis: Identify potential challenges in game development (e.g., graphics, gameplay balancing).
• Development: Create a simple prototype with basic gameplay mechanics and character movement.
• Evaluation: Gather feedback from testers on core gameplay elements and user interface.

Cycle 2: Enhanced Features

• Planning: Incorporate feedback, add features like power-ups, obstacles, and level design.
• Risk Analysis: Assess potential issues with game difficulty, monetization (ads or in-app purchases).
• Development: Expand the game with new features, improve graphics, and add sound effects.
• Evaluation: Conduct user testing, analyze gameplay metrics, and gather player feedback.

Cycle 3: Full Release

• Planning: Finalize game content, marketing strategy, and app store submission.
• Risk Analysis: Identify potential launch issues, competition analysis.
• Development: Bug fixing, optimization, and polishing the game for release.
• Evaluation: Monitor app store performance, collect user reviews, and plan updates.