Software Development Life Cycles

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What is a major limitation of the waterfall model?

It is only suitable for small and simple systems
It is not an efficient process
It assumes that the requirements of a system can be frozen before the design begins (correct)
It does not allow for prototyping

When is the waterfall model most effective?

When the developing organization is quite familiar with the problem domain and the requirements are quite clear (correct)
When the problem domain is unfamiliar and the requirements are unclear
When the system is novel and has no existing manual process
When the client has limited input in the development process

What is the primary goal of a prototyping-based development process?

To counter the limitations of the waterfall model (correct)
To reduce the development time and cost
To create a final product that meets the client's requirements
To ensure that the client is involved in the development process

What is an advantage of prototyping in systems development?

It allows the client to 'play' with the prototype and provide valuable input (B) Signup and view all the answers

What is prototyping effective for?

Complicated and large systems with unclear requirements (A) Signup and view all the answers

What is another benefit of prototyping in systems development?

It is an effective method of demonstrating the feasibility of a certain approach (A) Signup and view all the answers

What is the primary purpose of prototyping in software development?

To reduce the risks associated with the project (A) Signup and view all the answers

What type of systems is the prototyping process model suitable for?

Large systems with no manual process to define the requirements (C) Signup and view all the answers

What is a characteristic of the iterative-enhancement model?

It breaks down the software into several modules (D) Signup and view all the answers

What is the benefit of using prototyping in software development?

It results in a higher quality of software (D) Signup and view all the answers

What is the primary difference between the prototyping process model and the iterative-enhancement model?

The prototyping process model is a linear sequential approach, while the iterative-enhancement model is an iterative approach (B) Signup and view all the answers

What is the outcome of using the prototyping process model in software development?

The system meets the user's requirements (D) Signup and view all the answers

What is the primary advantage of the waterfall model?

It is straightforward and divides the large task of building a software system into a series of cleanly divided phases (B) Signup and view all the answers

What percentage of maintenance costs are attributed to perfective maintenance?

Over 50% (D) Signup and view all the answers

What is the primary difference between beta testing and acceptance testing?

Beta testing is performed by customers, while acceptance testing is performed by the software-development team (B) Signup and view all the answers

What is a disadvantage of the waterfall model?

It assumes that the requirements of a system can be frozen before the design begins (B) Signup and view all the answers

What is the term that might be more suitable than 'maintenance'?

Evolution (A) Signup and view all the answers

What is a characteristic of the waterfall model?

It follows the 'big bang' approach (C) Signup and view all the answers

Study Notes

Waterfall Model

Despite limitations, the waterfall model is still used when the developing organization is familiar with the problem domain and software requirements are clear.
The waterfall model is efficient in such cases.
The model assumes that requirements can be frozen before design begins.
It is not suitable for complicated and large systems with no manual process to determine requirements.

Prototyping Process Model

Goal is to counter the limitation of the waterfall model by building a throwaway prototype to understand requirements.
Suitable for complicated and large systems with no manual process to determine requirements.
Helps determine system requirements by letting clients "play" with the prototype.
Effective method for demonstrating feasibility of a certain approach, especially for novel systems.

Testing

Beta testing is performed by a group of friendly customers in the presence of the software-development team.
Acceptance testing is performed by customers themselves.
Software is installed at the customer's site if successful in acceptance testing.

Delivery and Maintenance

Delivery of software is often done in two stages.
Cost of maintenance is often more than 60% of the total cost of software.
Over 50% of maintenance costs are attributed to perfective maintenance.
Evolution is a better term than maintenance.

Advantages of Waterfall Model

Simplicity and straightforwardness divide the task of building a software system into cleanly divided phases.
Easy to administer in a contractual setup.
Each phase completion is accompanied by payment from the customer to the developing organization.

Disadvantages of Waterfall Model

Assumes that requirements can be frozen before design begins, requiring hardware choice.
Encourages "requirements bloating".
Follows the "big bang" approach, delivering the entire software in one shot.
Is a document-driven process requiring formal documents at each phase.

Prototyping Process

Users are given an opportunity to use and explore the prototype, providing feedback to developers.
Feedback is used to modify the prototype until the required prototype is reached.