Hanndouts

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Paper Coder CSCC-25
System Analysis and Design
DCS-JMI Jan 2019
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Learning Objectives

• System Philosophy System Thinking
• To provide you with the understanding and new
  ways of looking at information in the world in
  order to solve business problems
• To learn methods for analyzing designing
  systems to solve problems using technology.
• SAD deals with planning the development of IS
  through understanding and specifying in detail
  what a system should do and how the components
  of the system should be implemented and work
  together.

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Global Village
IPDET
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What is a system?
Unit - I
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What is a system?

• System

INPUT
OUTPUT
PROCESS
FEEDBACK
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What is a system?

• A collection of inter-related parts
• which act as a whole
• towards a common goal
• e.g.. The library system

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What is a System?

• A collection of parts that work together to
  achieve a goal/task
• Examples
• Solar system
• Digestive systems
• Public transport system
• Central heating system
• Computer system
• Information system
• A set of objects and relationships among the
  objects viewed as a whole and designed to
  achieve a purpose

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System

• A system is an interrelated set of business
  procedures used within one business unit working
  together for a purpose
• A system has nine characteristics
• A system exists within an environment
• A boundary separates a system from its
  environment

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Characteristics of a System

1. Components
2. Interrelated Components
3. Boundary
4. Purpose
5. Environment
6. Interfaces
7. Constraints
8. Input
9. Output

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Systems Thinking Advantages

• Allows you to think about an organization, a
  process, a program, etc. at a higher, more
  abstract level
• Reveals problems that are obscured by physical
  details
• Abstractions are easier to manipulate
• Promotes creativity

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Why System Failed/Abandon?

• When analysts tried to build wonderful systems
  without understanding organization (User Req.)
• Primarily goal
• ..to create value for the organization.
• Systems analyst - a key person (among
  stakeholders) analyzing the business
  problems/issues, identifying opportunities for
  improvement, and designing IS accordingly (to
  implement these ideas).
• It is important to understand and develop through
  practice the skills needed to successfully
  design and implement new application/IS .

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INFORMATION SYSTEMS
INFORMATION SYSTEMS
MANAGEMENT
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What Is an IS?

• System a collection of elements and procedures
  that interact (coordinate cooperate) in order
  to accomplish a mutual common goal.
• IS a collection of people, hardware, software,
  data, and procedures that interact to generate
  information to support the users of an
  organization.

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WHAT IS INORMATION SYSTEM ?
ENVIRONMENT Customers Suppliers
ORGANIZATION INFORMATION SYSTEM OUTPUT FEEDBACK
INPUT
PROCESS
Regulatory Stockholders Competitors Agencies
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The System Process
input input input
output output output
Feeback and Control Loop
The System's Environment (constantly changing)
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System properties

• Systems can be seen, organized, and described in
  different ways
• Systems within systems
• Open systems
• Have interaction with the outside world
• React to and accommodate changes in their
  environments
• Synergy - elements work together beneficially

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System features

• Purpose
• Processes
• Data
• Structure/Organisation
• Context

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APPROACHES TO INFO SYSTEMS
TECHNICAL APPROACHES
COMPUTER SCIENCE
MANAGEMENT SCIENCE
MIS
SOCIOLOGY
POLITICAL SCIENCE
PSYCHOLOGY
BEHAVIORAL APPROACHES
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Information Systems Projects Main Reasons
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Participants in Systems Development
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Lets have Some .
Thought Provoking !!
Questions?
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Questioning???
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Why Questioning?
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Some Critical Questions

• What should we develop?
• When should we develop?

Based on goals strategic Direction OF
Organization.

• Who will be responsible for the development?
• For whom, we should develop?
• How should we proceed?
• ..Methodology ??
• ..SSAD

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Stakeholders Their Perspectives
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Steering committee
User 1
I nformation technology vendors
User 2
Systems analyst
Applications programmers
User N
Network administrator
M anagement/ system owner
Database administrator
I nterface design expert
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Systems Analysts Diverse Roles

• Three major roles
• consultant (outsider)
• supporting expert (insider)
• agent of change (shaker)
• Skills of a Systems Analyst
• Analytical
• Technical
• Management
• Interpersonal

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Qualities of Systems Analyst

• Problem solver
• Communicator
• Translator
• Facilitator
• Strong personal and professional ethics
• Self-disciplined and self-motivated

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• The force behind the effective functioning of
  any organization.?

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The force behind the effective functioning of
any organization is a system.
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3 Level Pyramid Model (Management Triangle)
Based on the type of decisions taken at different
levels in the organization
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Management Triangle
5 level pyramid model based on the processing
requirement of different levels in the
organization
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Business plus IT-Solution Focus
Analysis Design
Plan
Implementation
IT-Solution Focus
Business Focus
Rigorous
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What is Methodology?
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What Is a Methodology?

• A Formalized Approach or series of steps
• Writing code without a well-thought-out system
  request may work for small programs, but rarely
  works for large ones.
• Structured Design
• Projects move methodically from one step to the
  next step..Generally, a step is finished before
  the next one begins.

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Systems Development Life Cycle
Systems Investigation Product Feasibility Study
Systems Investigation Product Feasibility Study
Systems Analysis Product Functional Requirements Systems Design Product System Specifications Systems Implementation Product Operational System Systems Analysis Product Functional Requirements Systems Design Product System Specifications Systems Implementation Product Operational System
Systems Maintenance Product Improved System
Systems Maintenance Product Improved System
Understand Business Problem or Opportunity
SDLC
Develop an Information System Solution
Implement Information System Solution
Traditional Approach
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SDLC -Phases
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Most Significant Step/Phase in SDLC
...Quite Challenging Factors/Aspects
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Most Significant Step/Phase in SDLC
...Quite Challenging Factors/Aspects

• Problem Identification
• ..Outline Specific / Exact Problem Area
• Preliminary Investigation
• Whether it makes to launch the Project.
• See if it is worthy of further study (detailed)
  
• Understanding User Requiremnts/Concerns
• ..What are the exact User Requirements?
• Outline Domain (Scope/Boundary)

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Why ?

• Such a Situation or Scenario ??
• Challenging Complex or Difficult Task ??

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Special Professional Traits
What are Those?

• Special Traits Required to tackle Such a Complex
  Situation or Scenario
• . What are Those Traits?

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Preliminary Investigation

• Identify Problem Areas
• (Outline The Domain).
• The purpose of PI
• Ensure whether it makes sense to launch project
• Define evaluate problem at hand- (Quickly)
• See if it is worthy of further study (detailed)
• Suggest some possible courses of
  actions/alternatives (if there is/are any)

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Preliminary Investigation

• What will be the Output of PI?

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Preliminary Investigation

• Feasibility Report
• Yes !!!
• Can Go For System Analysis
• .Detailed System Study

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What is System Analysis?
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What is System Analysis?

• The dissection of a system into its component
  pieces for purposes of studying how those
  component pieces interact and work. Formal
  Definition.
• Systems analysis is done for the purpose of
  subsequently performing a systems synthesis.
• What is Systems synthesis?

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What is System Synthesis ?

• Systems synthesis is the re-assembly of a
  systems component pieces back into a whole
  system hopefully an improved system (Updated
  Version).

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What is System Analysis ?

• Survey and Planning of the system and project,
• Study and Analysis of the existing business and
  IS, and
• Definition of Business Requirements and
  Priorities for a new or improved system.
• ..Leads to Logical design.
• Systems analysis is driven by business concerns,
  specifically, those of system users (end users).

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Systems Analysis

• Two Objectives/Tasks -
• What are Those Specific Objectives?

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Systems Analysis

• Two Objectives/Tasks -
• First Objective Data collection
• Information gathering about how work is
  done/performed in application area/domain.
• To ascertain what Information Users Need.
• What Exactly are The User Requirements?

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Systems Analysis

• Two Objectives/Tasks -
• 2. Second Objective Data Analysis
• Data Analysis Tools
• DFD, Decision Tables/Trees and Checklists
• Documentation includes any instruments used in
  the data/information gathering stage, as well as
  resulting diagrams, Tables, Trees, checklists,
  etc.

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The Project

• Moves systematically through phases where each
  phase has a standard set of outputs
• Produces project deliverables
• Uses deliverables in implementation
• Results in actual information system
• Uses gradual refinement

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Project Phases

• Planning
• Why build the system?
• Analysis
• Who, what, when, where will the system be?
• Design
• How will the system work?
• Implementation
• System delivery

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Processes and Deliverables
Process Product
Planning
Project Plan
Analysis
System Proposal
Design
System Specification
New System Maintenance Plan
Implementation
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Underlying Principles

1. Get the owners and users involved
2. Use a problem-solving approach
3. Establish phases and activities
4. Establish standards for consistent development
   and documentation
5. Justify systems as capital investments
6. Dont be afraid to cancel or revise
7. Divide and conquer
8. Design systems for growth and change

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