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Systems Analysis and Design is the process people use to create (automated) information systems
SystemsAnalysis& Design
InformationSystem
2
Information Systems Engineering!Software Engineering!
Information Systems Development!Systems Engineering!
Systems Analysis and Design!
Other names...!
Whichone?
Is there an “official” name?
3
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
Time5
SYSTEMS ANALYSIS AND DESIGN: A Complete (Formal)
Perspective
• Systems Planning
• Systems Analysis
• Systems Design
• Systems Implementation
• Systems Evolution
Planning
Evolution
Implementation Design
Analysis
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• Name & Address Book• CD Collection• Course Registration• Reservations• Student Grades• Payroll• ATM machine & Banking in General• Check-Out Counters at Retail Stores• Order Fulfillment - Mail or Web Ordering• Manufacturing• Securities Portfolio Management• Space Shuttle Flight• Election Results• 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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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:• supports policies & procedures• has three components - data,
people, procedures - in addition to
the six general system components
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(input, output, processing, control, feedback and boundary)
An AUTOMATED INFORMATION SYSTEM IS:
a type of fabricated system
used by one or more persons
to help them accomplish some task or assignment they have
utilizes hardware and softwarepeople
procedures
data
software
hardware13
• DATA - input, output, or already stored electronically
• FUNCTIONS - transformations or actions taken
• BEHAVIOR - 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)14
• 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 SYSTEMS ANALYSIS and DESIGN produce
information systems that are:
used internally within the organization
sold commercially via mail/web order or retail store
imbedded in products
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Initially, problem domains (areas) tend to have poorly defined BOUNDARIES
Problem domain SOLUTIONS are artificial
Problem domains are DYNAMIC
Problem domain solutions usually require INTERDISCIPLINARY knowledge and skills
Systems Analyst’s KNOWLEDGEBASE is continually expanding
Systems Analysis and Design is a highly COGNITIVE activity
Working 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• 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 fixed”
• Opportunities - “good deals”
• 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)• Conversion - old to new• Training• Implementation• Evolution - maintenance & enhancements
SYSTEMS DEVELOPMENT LIFE CYCLE (SDLC)SYSTEMS DEVELOPMENT LIFE CYCLE (SDLC)A
naly
sis
Desig
n
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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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• 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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