SDLC

During our college days, we used to start developing code once the requirement is given.But this is ok when developing application with one or two classes.

But when developing bigger application you may be stuck in the middle of the development.Or for example we have developed one application and delivered it to the customer.If there is a mismatch in the requirement after delivery then the entire effort will lost and developer needs to code it again.

In order to overcome these problem experts come up with an idea called SDLC.

SDLC stands for Sofware Development Life Cycle

This is the step of process to follow for the development of software application

SDLC makes your application more reliable and efficient.

There are lot of SDLC models are available

1) Waterfall Model
2) Iterative Model
3) V-Model
4) Spiral Model
5) Big Bang Model
6) RAD Model,etc.,

Here we  will see about only waterfall model and this is a basic model and all the other models are derived from this model.

1)Requirement Ananlysis and Definition  

•  It means getting the requirement (functionality and constraints) from the end-user
•  Requirement Specification Document will be prepared which serves as the input for the next phase of the   model

2)System Design

 Before we start developing we need to identify how the system should look like?

In this phase the requirements from the first phase will be studied and based on that design doc will be prepared using any one of the modelling tools like UML, Rational Rose,State diagram,Sequence diagram,etc,

3) Implementation and unit testing
 
 Here the actual coding will be done.The total application divided into number of unit and each will be developed and tested by the developer.
 Pls note that unit testing will be done by developer not the tester.

4)Integration Testing

 In the previous phase, the total application is divided into small units and are developed and tested.Here those units will be integrated and tested.

 Integration testing simply means whether all the unit coordinate to each other and to check whether the application works as expected.

5)Operation and Maintenance

 This is the last phase of SDLC.In this phase, issues in the deployed application will be resolved.And the maintenace will continue for long so we can say waterfall model will never ends.