Introduction to Information Technology
2nd Edition
Turban, Rainer & Potter
© 2003 John Wiley & Sons, Inc.
Information Systems Development
Prepared by:
Roberta M. Roth, Ph.D.
University of Northern Iowa
Introduction to Information Technology, 2nd Edition
Turban, Rainer & Potter
© 2003 John Wiley & Sons, Inc.
14-1
Chapter Preview
 In this chapter, we will study:
 Planning process for IS application development
 The process of developing systems as outlined in the
SDLC
 Alternatives to the SDLC and why they are useful
 Ways to obtain applications from outside the
organization
 Methods that are useful in developing
Internet/intranet applications
Introduction to Information Technology, 2nd Edition
Turban, Rainer & Potter
© 2003 John Wiley & Sons, Inc.
14-2
Information Systems Planning Process
Organization
Mission
Business
Assessment
Organization
Strategic Plan
Current Information
Technology Architecture
IS Strategic Plan
New Information Technology Architecture
IS Operational Plan
IS Development Projects
Introduction to Information Technology, 2nd Edition
Turban, Rainer & Potter
© 2003 John Wiley & Sons, Inc.
14-3
IS Strategic Plan
 Objectives
Align with the organization’s strategic plan
Provide for an IT architecture that enables
users, applications, and databases to be
seamlessly networked and integrated
Allocate IS development resources efficiently
among competing projects, so the projects can
be completed on time, within budget, and
have required functionality
 Issues - efficiency; effectiveness; competitiveness
Introduction to Information Technology, 2nd Edition
Turban, Rainer & Potter
© 2003 John Wiley & Sons, Inc.
14-4
IS Operational Plan
 Mission - the mission of the IS function
 IS environment - the summary of the information needs of the
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functional areas and of the organization as a whole
Objectives - the IS function’s current best estimate of its goals
Constraints - technological, financial, and personnel limitations on
the IS function
Long-term systems need - a summary of the processes needed by
a company and the IS projects selected to support them and reach
organizational goals
Short-range plan - an inventory of current projects, and a detailed
plan of projects to be developed or continued during the current year
Introduction to Information Technology, 2nd Edition
Turban, Rainer & Potter
© 2003 John Wiley & Sons, Inc.
14-5
Information Systems Development Terms
 SDLC - the development method used by most
organizations today for large, complex systems
 Systems Analysts - IS professionals who specialize in
analyzing and designing information systems
 Programmers - IS professionals who modify existing
computer programs or write new computer programs to
satisfy user requirements
 Technical Specialists - experts in a certain type of
technology, such as databases or telecommunications,
who help create information systems
Introduction to Information Technology, 2nd Edition
Turban, Rainer & Potter
© 2003 John Wiley & Sons, Inc.
14-6
The Traditional SDLC
(1) Systems Investigation
An eight-stage systems
development life cycle
(SDLC)
(2) Systems Analysis
(3) Systems Design
(4) Programming
(5) Testing
(6) Implementation
(7) Operation
(8) Maintenance
Go Back to a previous Stage or Stop
Introduction to Information Technology, 2nd Edition
Turban, Rainer & Potter
© 2003 John Wiley & Sons, Inc.
14-7
Phases in SDLC
 System Investigation
 Feasibility study determines the probability of success of proposed
system’s development project. Includes …
• Technical feasibility (will we be able to build the system?)
• Economic feasibility (how much will it cost to build the system and
how much will it benefit us?)
• Behavioral feasibility (if we build the system, will it be accepted and
used?)
 Systems Analysis
 Examines the business problem(s) that the organization plans to
solve with information systems
 Determines what the new system must do by examining:
• Strengths and weaknesses of the existing system
• Functions that the new systems must have to solve the business
problem(s)
• User information requirements for the new system
Introduction to Information Technology, 2nd Edition
Turban, Rainer & Potter
© 2003 John Wiley & Sons, Inc.
14-8
Phases in SDLC (continued)
 Systems Design
 Describes how the system will fulfill the user requirements
 Develop both logical design and physical design
 Output => technical design or system specification…
• system outputs, inputs, and user interfaces
• hardware, software, databases, telecommunications, personnel, and
procedures
• how these components are integrated
 Programming
 the translation of the design specifications into computer code
 structured programming techniques improve the logical flow of
the program by decomposing the computer code into modules
Introduction to Information Technology, 2nd Edition
Turban, Rainer & Potter
© 2003 John Wiley & Sons, Inc.
14-9
Phases in SDLC (continued)
 Testing
 Checks to see if the computer code will produce the expected and
desired results under certain conditions
 Implementation
 The process of converting from the old system to the new system
 Four major conversion strategies
• Parallel conversion: the old and new systems operate
simultaneously for a period of time
• Direct conversion: the old system is cut off and the new
systems is turned on at a certain point in time
• Pilot conversion: introduces the new system in one part of the
organization
• Phased conversion: introduces components of the new system
in stages
Introduction to Information Technology, 2nd Edition
Turban, Rainer & Potter
© 2003 John Wiley & Sons, Inc.
14-10
SDLC Phases
 Operation
the new system will operate for a period of
time, until it no longer meets its objectives
 Maintenance (simultaneous with Operation)
debugging the programs
updating the system to accommodate changes
in business conditions
adding new functionality to the system
Introduction to Information Technology, 2nd Edition
Turban, Rainer & Potter
© 2003 John Wiley & Sons, Inc.
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