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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