3. Waterfall model
Waterfall model is a famous
and good version of
SDLC(System Development Life
Cycle) for software
engineering. The waterfall
model is a linear and
sequential model, which
means that a development
phase cannot begin until the
previous phase is completed.
We cannot overlap phases in
waterfall model.
4. Similarly waterfall model also works, once one phase of
development is completed then we move to the next
phase but cannot go back to the previous phase.
• The waterfall model is a sequential project management
methodology where one phase completely finishes
before the next phase begins.
• There are 6 phases in a simple waterfall model:-
requirements, design, implementation, verification,
deployment and maintenance
5. V-Model
• The V-model is a graphical
representation of a systems
development lifecycle.
• It is used to produce
rigorous development
lifecycle models and project
management models.
• The V-model falls into
three broad categories, the
German V-Modell, a
general testing model, and
the US government
standard.
6. V-Model Design
Requirements Gathering and Analysis: The first phase of the V-Model is
the requirements gathering and analysis phase, where the customer’s
requirements for the software are gathered and analyzed to determine the
scope of the project.
Design: In the design phase, the software architecture and design are
developed, including the high-level design and detailed design.
Implementation: In the implementation phase, the software is built based
on the design.
Testing: In the testing phase, the software is tested to ensure that it meets
the customer’s requirements and is of high quality.
Deployment: In the deployment phase, the software is deployed and put
into use.
• Maintenance: In the maintenance phase, the software is maintained to
ensure that it continues to meet the customer’s needs and expectations.
7. Advantages of V-Model
This is a highly disciplined model
and Phases are completed one at a
time.
V-Model is used for small projects
where project requirements are
clear.
Simple and easy to understand and
use.
This model focuses on verification
and validation activities early in
the life cycle thereby enhancing
the probability of building an error-
free and good quality product.
• It enables project management
to track progress accurately.
Disadvantages of V-Model
High risk and uncertainty.
It is not good for complex and
object-oriented projects.
It is not suitable for projects where
requirements are not clear and
contain a high risk of changing.
This model does not support
iteration of phases.
It does not easily handle concurrent
events.
Inflexibility: The V-Model is a linear
and sequential model, which can
make it difficult to adapt to
changing requirements or
unexpected events.
• Time-Consuming: The V-Model can
be time-consuming, as it requires
8. Incremental model
• Incremental Model is a process of
software development where
requirements divided into multiple
standalone modules of the software
development cycle.
• In this model, each module goes
through the requirements, design,
implementation and testing phases.
• Every subsequent release of the
module adds function to the
previous release. The process
continues until the complete system
achieved.
9. The various phases of incremental model are as follows:
1. Requirement analysis: In the first phase of the incremental model, the product analysis
expertise identifies the requirements. And the system functional requirements are understood
by the requirement analysis team. To develop the software under the incremental model, this
phase performs a crucial role.
2. Design & Development: In this phase of the Incremental model of SDLC, the design of the
system functionality and the development method are finished with success. When software
develops new practicality, the incremental model uses style and development phase.
3. Testing: In the incremental model, the testing phase checks the performance of each
existing function as well as additional functionality. In the testing phase, the various methods
are used to test the behavior of each task.
4. Implementation: Implementation phase enables the coding phase of the development
system. It involves the final coding that design in the designing and development phase and
tests the functionality in the testing phase. After completion of this phase, the number of the
product working is enhanced and upgraded up to the final system product
10. Advantage of Incremental Model:-
Errors are easy to be recognized.
Easier to test and debug
More flexible.
Simple to manage risk because it handled during its iteration.
• The Client gets important functionality early.
• Disadvantage of Incremental Model:-
• Need for good planning
• Total Cost is high.
• Well defined module interfaces are needed.
