system development life cycle Presentation

Copyright © 2006 by The McGraw-Hill Companies, Inc. All rights reserved.

Introduction of Topic

System development life cycle



Group members

Muhammad Saleem

Muhammad Haris

Shazia Aziz

Muhammad Saleem

Muhammad Haris

Shazia Aziz

Systems Development Life Cycle

• Organized way to build information systems

• Consists of six phases

The phases are called the life cycle because they cover the entire life of an information system

SDLC


• Phase 1: preliminary investigation This phase is ground level and

initial phase of SDLC.it is too much time consuming phase, almost half of the time to complete the SDLC is taken by this pahse.The main objectives of this phase are:

Conduct the preliminary analysisPropose alternative solutionDescribe the costs and benefitsSubmit the report


1-Conduct the preliminary investigation

To find the objectives of organizationNature and scope of problemTo see the faults of older systemMake the ideas for the new system


2-Propose the alternative solution

No changeLittle changeTotally change


3-Describe cost and benefits• Whichever the alternative is chosen,

it will have cost and benefits. in this step, you need to indicate these.

4-Write a report Submission of prepared

report about new software. this report is also called the feasibility report.

• In this report you should describe the solution,cost,benefits etc


Phase 2: Systems analysis

After preparation of the feasibility report the system is analyzed accordingly.

• The main objectives of this phase are– Gather data– Analyze the data– Write a report


1-Gather data:-- data is gathered through the

different written documents, interview employees and managers, develop questionnaires and by observing people.

2-Analyze data:-- Once the data has been

gathered, many analytical or modeling tools are used.


Modeling tools:-

Modeling tools enable a system analyst to present representation of a system. There are different tools for analyzing data these are:

DFD (data flow diagram)ERD (entity relationship diagram) CASE (computer aided software

engineering)


DFD (data flow diagram)

it is a modeling tool which shows the flow of data through a system. some symbols are used in DFD


• DFD (data flow diagram)

• Provide a logical map of the problem • Defines the data stores and

processes • Shows how data moves and changes

Example Flow Chart Symbols

Process

PredefinedProcess

AlternateProcess Decision Data

Document Terminator

ManualInput

Extract

Merge

Connector

Delay DataStorage

DisplayOff page

Connector

ManualOperation

Preparation


• Example


• Phase-3 Design the system

Do the preliminary designDo a detail designWrite a report


• Do the preliminary design prototyping is often done at

this stage.. Prototyping prototyping refers to using

workstations,CASE tools and other software applications to build working models of system components so that they quickly tested and evaluated.Thus a prototype is a limited working system.

•


• Analysis concentrates on what the purposed system should do, design concentrates on how the system will accomplish those goals.


• Translating alternative solution generated by analysis phase into detailed logical and physical system specifications.– Logical design: not tied to any hardware

or software platform– Physical design: specific programming

languages, databases, architectures


– Define database, load with data, and review with users

– Define inputs, and review with users– Define outputs, and review with users– Define interfaces, and review with users– Define other controls, and implement.

Conclusion


End of topicEnd of topic

Documents

system development life cycle Presentation