software Engineering model

1. Software Engineering
Various SDLC Model are:-
1) Waterfall Model:-
It is one of the simplest models.
This model is easy to implement.
This model moves from top to bottom and it cannot be revert back.
Advantage of Waterfall model:-
 Relatively easy to understand and manage
 Each phase of development proceeds sequentially
 Allows managerial control where a schedule with deadlines is set
for each stage of development
 Helps in controlling schedules, budgets, and documentation

2. Disadvantage of Waterfall Model:-
 Requirements need to be specified before the development
proceeds.
 The changes in the requirements in later phases of the waterfall
model cannot be done
 Does not involve risk management
2) Prototyping Model:-
Applied when there is an absence of detailed information regarding
input and output requirements in the software. Increases flexibility
of the development process by allowing the user to interact and
experiment with a working representation of the product known as
prototype.

3. Advantage of Prototype Model:-
 Provides a working model to the user early in the process
 Requirements are well classified here.
 Developer gain experience by developing this model.
 There is great involvement of user in the project.
Disadvantage of Prototype Model:-
 If the user is not satisfied by the developed prototype, then a new
prototype has to be developed
 Prototyping can lead to false expectations
 Developer loses focus of the real purpose of prototype and
compromise with the quality of the product
3) Spiral Model:-

4. This model combines the features of prototyping model and waterfall
model. This model is advantageous for large, complex and expensive
projects. This model emphasize on evaluating and resolving risk in
software project.
Advantage of Spiral Model:-
 This model avoids the problems resulting in risk-driven approach
in the software.
 This model specifies a mechanism for software quality assurance
activities.
 This model is Suitable for complex and dynamic projects
 In this model Estimation of budget and schedule gets realistic as
the work progresses.
Disadvantage of Spiral Model:-
 In this model assessment of project risks and its resolution is not an
easy task
 This model is Difficult to estimate budget and schedule in the
beginning.
4) RAD Model:-

5. This model Lays emphasis on delivering projects in small pieces. Large
project is divided into a series of smaller projects.Each of these smaller
projects are planned and delivered individually
Advantage of RAD model:-
 In this model deliverables are easier to transfer.
 This model provides greater flexibility.
 This model encourages user involvement.
Disadvantage of RAD model:-
 In this model projects fail if there is no commitment by the
developers or the users to get software completed on time.
 This model is not appropriate when technical risks are high.
5) V-Model:-
Determines the complex relationship between each phase of
software development and ensures that each phase of software
development is associated with testing.

6. Advantage of V model:-
 Covers all functional areas
 This model emphasizes the significance of testing and
ensures that testing is planned.
Disadvantage of V model:-
 In this model the processes are institutionalized during the project
and when the project is finished, they are abolished.
Conclusion:-From the above model I conclude that RAD Model is best
model to implement in any software project.