INTRODUCTION TO SYSTEM ANALYSIS AND DESIGN

Information
is data that has been transformed into output that is valuable to users
Data that is accurate and timely, specific and organized for a purpose, presented within a context that gives it meaning and relevance, can lead to an increase in understanding and decrease in uncertainty.


Components of Information Systems
Resources of people
Hardware
Software
Data
Networks
End users
IS Specialists

Hardware:
Machines: as computers and other equipment along with all data media, objects on which data is recorded and saved.
Computer systems: consist of variety of interconnected peripheral devices. Examples are microcomputer systems, midrange computer systems, and large computer systems.

Software Resources includes:
System software,
Application software,
Procedures,

Data:
Text data, consisting of sentences and paragraphs used in written communications; image data, such as graphic shapes and figures; and audio data, the human voice and other sounds, are also important forms of data

Data must meet the following criteria
Comprehensiveness:
Non-redundancy
Appropriate structure

Network
Communications media,
Network support

(TPS)

Function: Simple data processing system

Input: Transaction Events

Processing: Validation /Sorting/Listing/Merging/Updating/Calculation

Output: List/ details Report/ Action report/ Summary report

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(MIS)

Function: built on the data provided by the TPS

Input: Internal Transaction / Internal Files/Structured Data

Processing: Sorting/Merging/Summarizing

Output: Details Report/ Action report/ Summary report

(DSS)

Function: manipulate and build upon the information from a MIS and/or TPS to generate insights and new information

Input: Internal Transaction / Internal Files/ External Information

Processing: Modelling/Simulation/Analysis/Summarizing

Output: Summary report/ Forecast /Graph /plots

(EIS)

Input: External Data/Internal Files/ Pre-defined models

Processing: Summarizing/ Simulation / “Narrow Down”/“Drilled Down

Output: Summary report/ Forecast /Graph /plots

Object Oriented Analysis
Combines data & processes that act on the data into things called objects
Object is a member of a class, possess properties

Agile/Adaptive Method
Agile process determines the end result
Analysts should understand the pros and cons of any approach before selecting a development method

System Development Life Cycle
. Planning
. Analyze
Design
. Development
Testing
. Implementation
Maintenance

Types of Life Cycle Models
Waterfall model,
Spiral Model,
Iterative and incremental development,
Agile Model,
Prototyping model,
Rapid Application Development (RAD)'
Rapid Application Development (RAD)






Apply five basic guidelines for systems development
Develop a Plan, Involve Users and Listen Carefully to user, Use Project Management Tools and Techniques, Develop Accurate Cost and Benefits Information, Remain Flexible





Steps In Project Planning
project schedule
cost estimates
project plan
project personnel/project team

3 Key Steps in Project Planning

  1. Create a work breakdown structure.
  1. Identify task patterns
  1. Calculate the critical path