Software Development Life cycle (SDLC)

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Software Development Life cycle (SDLC)

Phases of SDLC

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•Requirement Analysis (Defining Requirement)

•Designing (Design)

•Coding (Implementation)

•Software Testing

•Deployment and Maintenance

Let Us discuss SDLC in detail• Requirement Analysis• It describe the “ WHAT” of a system.

• The objective which are to be achieved.

• According to IEEE ,RA, is the process of studying user’s need, refining s/w requirements.

• Cost benefit analysis.

• Performing feasibility study.

• Scheduling projects using both GANTT and Pert Chart

• Define SRS(Software requirements specification)

• Designing and constructing DFD (data flow diagram),ER diagram, data dictionary, object oriented diagram (Can Use UML)

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Let Us discuss SDLC in detail• Design• SRS is the input for the design phase.

• In this phase a logical system is built which fulfils the given requirements.

• Transforming customer’s requirements into a logically working system.

• It has mainly two phases:

[1] Primary Design Phase

system is designed at block level, Make the Blocks (Modules) .

[2] Secondary Design Phase

Detailed design of every block has to be performed.

• Design various data structures.

• It should precisely describe the system , so that developer can understand it. Flexibility should be there to change.

• Out put of the design phase is software design document (SDD).

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Let Us discuss SDLC in detail• Coding• SDD is the input for the implementation phase.

• According to the module specification design document is coded.

• Selection of the appropriate programming language, database if any required.

• SDD is now converted into HLL code, then it compiled and Run.

• Maintaining security

• Documentation of the source code.

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Let Us discuss SDLC in detail• Testing• Testing is the process of running the software on manually created

inputs to find the errors.

• An attempt to detect the errors.

• Testing is performed keeping the user’s requirements in mind before it is actually launched.

• White box testing , block box testing , other testing techniques are used.

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Let Us discuss SDLC in detail

•Maintenance • To rectify the errors which are encountered during the operation of the

software.

• Change the program according to increased requirements (h/w or s/w).

• There are three categories of maintenace

. Corrective

. Adaptive

. perfective

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