Evolutionary Model with real life examples | Software Engineering

Summary

This video script introduces the Evolutionary Model in software development, a blend of iterative and incremental approaches. It emphasizes the model's flexibility to adapt to changing customer requirements over time, unlike traditional models that lock requirements early. The script outlines the process of developing software in increments while incorporating iterative feedback loops for continuous refinement. Suitable for large, complex projects, the Evolutionary Model allows for early operational deployment and risk mitigation, though it requires highly skilled resources and may not be cost-effective for smaller projects.

Takeaways

• 🔧 The evolutionary model is a blend of iterative and incremental approaches in software development, allowing for both gradual feature delivery and continuous refinement.
• 🏗️ In the incremental model, the product is delivered in parts, starting with basic functionalities and building upon them with each iteration.
• 🔄 The iterative model emphasizes feedback loops after each development stage, enabling adjustments to plans and estimates based on customer input.
• 🔄 The evolutionary model accommodates changing customer requirements over time, unlike traditional models where requirements are fixed early on.
• 🏢 It is particularly suited for large, mission-critical projects where requirements and technologies are likely to evolve, such as infrastructure developments.
• 🚀 The model allows for an initial operating time to be reduced as parts of the system are deployed incrementally, providing early value to the customer.
• 🤝 Customer feedback is integral, with the model encouraging active engagement and the incorporation of suggestions into subsequent development cycles.
• 💡 The model requires a highly skilled team that can analyze risks and make informed decisions at each stage of development.
• 💼 It may not be cost-effective for smaller projects due to the overhead of managing iterative and incremental processes.
• 📈 The evolutionary model is depicted through a diagrammatic representation showing the progression from rough requirement specifications to the final, refined system.

Q & A

What is the evolutionary model in software development?

The evolutionary model is a combination of iterative and incremental models in the software development lifecycle. It allows for the development of software in stages, with continuous feedback and refinement based on customer requirements and changes over time.

How does the incremental model work?

In the incremental model, the complete product is not delivered at once. Instead, features are designed and delivered incrementally. After each set of features is delivered, the next version with additional features is developed and delivered, eventually leading to the complete software or system.

What is the main difference between the evolutionary model and the incremental model?

The evolutionary model differs from the incremental model by incorporating iterative development. This allows for feedback and changes in requirements, plans, and estimates after each increment is developed and delivered, making it more adaptable to changing needs.

Why is the evolutionary model referred to as 'Design a little, Build a little, Test a little, Deploy a little'?

This phrase describes the iterative nature of the evolutionary model, where development is done in small, manageable stages. After each stage, the product is tested, deployed, and then feedback is collected to refine the next stage of development.

Can you provide an example to illustrate the evolutionary model?

An example given in the script is the construction of a three-storey building. The ground floor is developed first, then the first floor, and finally the second floor, incrementally. However, if the project is large and complex like the Delhi metro, the requirements and plans may evolve over time, necessitating an iterative approach to adapt to changes.

What are some advantages of using the evolutionary model?

Advantages include the ability to start operating sooner, continuous refinement based on feedback, better risk analysis by highly skilled personnel, and suitability for large, mission-critical projects where requirements may change over time.

What are the disadvantages of the evolutionary model?

Disadvantages include its unsuitability for smaller projects due to potentially higher costs and complexity, and the requirement for highly skilled resources to manage the iterative and incremental processes effectively.

How does the evolutionary model handle changing customer requirements?

The evolutionary model accommodates changing customer requirements by incorporating iterative development, which allows for feedback and modifications after each increment is delivered. This flexibility ensures that the final product aligns with the current needs of the customer.

What is the role of feedback in the evolutionary model?

Feedback plays a crucial role in the evolutionary model by allowing developers to make necessary adjustments to plans, estimates, and requirements after each increment is developed and delivered. This iterative feedback loop ensures that the product evolves to meet the customer's expectations and changing needs.

How does the evolutionary model differ from the waterfall model?

The evolutionary model differs from the waterfall model by allowing for iterative development and feedback loops. Unlike the waterfall model, which is linear and does not support changes easily, the evolutionary model is more flexible and adaptive to changes in requirements and technology.

What is the significance of the SRS document in the context of the evolutionary model?

In the evolutionary model, the Software Requirements Specification (SRS) document is used to initially lock down the requirements. However, unlike in the waterfall model, the evolutionary model allows for these requirements to be revisited and changed as needed after each increment, based on feedback and changing conditions.