SYSTEMS SYSTEMS

ANALYSIS ANDANALYSIS AND

DESIGNDESIGN

INTRODUCTIONINTRODUCTION

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Course InstructorCourse Instructor

Er. Ashwani MalhotraEr. Ashwani Malhotra

( B.Tech(IT) , M.Tech(CSE) (Pursuing) )( B.Tech(IT) , M.Tech(CSE) (Pursuing) )

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What is Systems Analysis and What is Systems Analysis and Design (SAD)?Design (SAD)?

Systems Analysis: understanding and specifying in detail what an information system should do

• System Design: specifying in detail how the parts of an information system should be implemented

Why is it important? • Success of information systems depends on good

SAD • Widely used in industry - proven techniques • Part of career growth in IT - lots of interesting and

well-paying jobs! • Increasing demand for systems analysis skills

Systems Analysis and Design is the process people use to create (automated) information systems

SystemsAnalysis& Design

InformationSystem

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Information Systems Engineering!Software Engineering!

Information Systems Development!Systems Engineering!

Systems Analysis and Design!

Other names...!

Whichone?

Is there an “official” name?

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A title given to a person who studies the

problems and needs of an organization

looking for improvement opportunities.

Systems AnalystSystems Analyst

Other names:

• Software Engineer• Systems Engineer• Software Developer• Programmer/Analyst• Nerd or Hacker! (joking!)

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An idea Analysis Design andImplementation

CompletedInformation

System

SYSTEMS ANALYSIS AND DESIGN: A Condensed (Informal) Perspective

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SYSTEMS ANALYSIS AND SYSTEMS ANALYSIS AND DESIGNDESIGN: A Complete (Formal) : A Complete (Formal)

PerspectivePerspective

Systems PlanningSystems Planning

Systems AnalysisSystems Analysis

Systems DesignSystems Design

Systems Systems

ImplementationImplementation

Systems EvolutionSystems Evolution

Planning

Evolution

Implementation Design

Analysis

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System

Natural Fabricated

InformationSystems

Others

AutomatedInformation

Systems

Others

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Name & Address BookName & Address Book CD CollectionCD Collection Course RegistrationCourse Registration ReservationsReservations Student GradesStudent Grades PayrollPayroll ATM machine & Banking in GeneralATM machine & Banking in General Check-Out Counters at Retail StoresCheck-Out Counters at Retail Stores Order Fulfillment - Mail or Web OrderingOrder Fulfillment - Mail or Web Ordering ManufacturingManufacturing Securities Portfolio ManagementSecurities Portfolio Management Space Shuttle FlightSpace Shuttle Flight Election ResultsElection Results Video Games (Arcade and Home)Video Games (Arcade and Home)

Business “problems” come in all sizes and shapes!Business “problems” come in all sizes and shapes!

Examples:

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A SYSTEM is a set of:

interrelated

components

working together

for a common

purpose

System

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SYSTEM

boundary

inputs

outputs

processing

controls

feedback

A Generic System A Generic System ModelModel

(with Six (with Six Components)Components)

Examples:• Automobile• Student Registration System• Others...

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System Model HierarchySystem Model Hierarchy

Water Vehicles

Cruise Ship

Staterooms

Suprasystem

System

Subsystem

“bigger”

“smaller”

Template Example

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An INFORMATION SYSTEM is:

• a type of fabricated system

• used by one or more persons

• to help them accomplish some task or

assignment they have

people

procedures

data

An Information System:• includes the 3 aspects of a

system• supports policies &

procedures• has three additional

components - data, people,

procedures - in addition to

the six general system

components

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An An AUTOMATED INFORMATION SYSTEMAUTOMATED INFORMATION SYSTEM IS: IS:

a type of fabricated systema type of fabricated system

used by one or more personsused by one or more persons

to help them accomplish some task to help them accomplish some task

or assignment they haveor assignment they have

utilizes hardware and software in utilizes hardware and software in

addition to data, people, proceduresaddition to data, people, procedures

… …plus all the aspects of a systemplus all the aspects of a system

people

procedures

data

software

hardware15

DATA - input, output, or already stored DATA - input, output, or already stored

electronicallyelectronically

FUNCTIONS - transformations or actions takenFUNCTIONS - transformations or actions taken

BEHAVIOR - the observable effects from interactionBEHAVIOR - the observable effects from interaction

DATA FUNCTIONS

BEHAVIOR

An An AUTOMATED INFORMATION AUTOMATED INFORMATION SYSTEMSYSTEM has three basic has three basic characteristics to consider:characteristics to consider:

(Plus the six system components: input, output, processing, control, feedback and boundary)16

Systems Analysis and Design is the process people use to create (automated) information systems

people

procedures

data

software

hardware

SA&D

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The people who do The people who do SYSTEMS ANALYSIS and DESIGNSYSTEMS ANALYSIS and DESIGN

produce information systems that are:produce information systems that are:

used internally within the organizationused internally within the organization

sold commercially via mail/web order or retail storesold commercially via mail/web order or retail store

imbedded in productsimbedded in products

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Initially, problem domains (areas) tend to have poorly defined Initially, problem domains (areas) tend to have poorly defined

BOUNDARIESBOUNDARIES

Problem domain SOLUTIONS are artificialProblem domain SOLUTIONS are artificial

Problem domains are DYNAMICProblem domains are DYNAMIC

Problem domain solutions usually require INTERDISCIPLINARY Problem domain solutions usually require INTERDISCIPLINARY

knowledge and skillsknowledge and skills

Systems Analyst’s KNOWLEDGEBASE is continually expandingSystems Analyst’s KNOWLEDGEBASE is continually expanding

Systems Analysis and Design is a highly COGNITIVE activitySystems Analysis and Design is a highly COGNITIVE activity

Working with PEOPLEWorking with PEOPLE

What makes Systems Analysis What makes Systems Analysis and Design a difficult activity?and Design a difficult activity?

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Systems Analyst’s interactions with people during Systems Analysis & Design

SYSTEMSANALYST

Users*SteeringCommittee*

Vendors

Programmers& Tech. Staff

DatabaseAdministrators

Managers*

* = Stakeholders

Systems Analystmay be acting asa Project Managerfor some of theseinteractions.

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Studies the problems and needs of

an organization looking for

improvement opportunities for:

increasing revenue/profit

decreasing costs

improving quality of service

What does a Systems Analyst do?What does a Systems Analyst do?

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Effective and efficient:

CAPTURE of input data

PROCESSING & STORAGE of data

DELIVERY of timely and accurate

information

What is a Systems Analyst responsible for?What is a Systems Analyst responsible for?

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Concepts & Principles

Environments/Tools

ProblemSolving &PeopleSkills

Methods & Techniques

Methodologies

Skills and Competencies of a Systems Analyst

• Functional Business Knowledge

• Verbal & written communication skills

• Systems Analysis and Design work experience

PLUS:

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Requirements Specification(3)

General Model of Information Systems Development (“Partnership”)

Stakeholder

InformationTechnology

Staff

AnalysisDesign

andImplementation

Requirements(1) Continued

Involvement(5)

InformationSystem (6)

ProblemDefinitionSkills (2)

ProblemSolutionSkills (4)

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Systems Analysis and Design Activities and Deliverables

ANALYSIS

Activities:

• Systems Planning• Feasibility Study (optional)• Requirements Determination• Conceptual Design• User Acceptance• Prototyping (optional)

Deliverables:• Requirements Specification• Prototype (optional)

DESIGN

Activities:

Deliverable:

• Physical Design• Prototyping (optional)• Software Construction/Purchase• User Documentation - “Deliverable”• Testing• Training• User Acceptance• Conversion• Implementing the system

• Information System

• Project Management • Project Documentation - “Scaffolding”

Two (2) additional on-going activities:

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Labor intensive

Smallest team = you

Next smallest team = you and one other (user)

Average team = several systems analysts and

users

Articulation of the business problem is difficult

Users and systems analysts come in all sizes and

shapes

Systems Analysis and Design Project ObservationsSystems Analysis and Design Project Observations

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Problems - “something needs to be Problems - “something needs to be

fixed”fixed”

Opportunities - “good deals”Opportunities - “good deals”

Directives - “do it…or else…”Directives - “do it…or else…”

Where Do Systems Analysis Where Do Systems Analysis and Design Projects Come and Design Projects Come

From?From?

... and are bounded by Constraintsand are bounded by Constraints

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Planning Feasibility Study (optional) Requirements Determination Conceptual Design Physical Design Construction and/or Purchase

(prototype) Training Conversion - old to new Implementation Evolution - maintenance &

enhancements

SYSTEMS DEVELOPMENT LIFE CYCLE (SDLC)SYSTEMS DEVELOPMENT LIFE CYCLE (SDLC)A

naly

sis

Desig

n a

nd

Imp

lem

en

tati

on

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Sequential or Traditional SDLC1. Planning for an information system2. Feasibility Study (optional)3. Requirements Determination (gathering)4. Conceptual design5. Physical design and/or purchase and/or prototyping6. Conversion from current system to new/changed system7. Training8. Implementation9. Evolution for enhancements and maintenance

Waterfall or Staircase SDLCPlanning

Feasibility Study

Requirements DeterminationConceptual Design

Physical DesignConversion

TrainingImplementation

Evolution

“Begin”

“End”

“Begin”

“End”

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Planning

Feasibility Study

Requirements Determination

Conceptual Design

Physical Design

Conversion

Training

Implementation

Evolution

Iterative SDLC

Risk Analysis

Spiral SDLC

SDLC Activities

Verification/Test

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31Boehm, 1988

The system is for the user

A Work Breakdown Structure should be used (ie., SDLC)

Systems analysis and design is iterative and overlapping

Information systems are capital investments for the business

Project manager may have the authority to cancel a project

Project documentation is important all along the way

Senior management approval/support is very important

Principles to Guide Systems Analysis & Design

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ThanksThanks