Information Systems Development

lumpysteerΛογισμικό & κατασκευή λογ/κού

2 Δεκ 2013 (πριν από 4 χρόνια και 4 μήνες)

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Information Systems Development

Panagiotis Kanellis
Επιστημονικός Συνεργάτης Τμήματος Πληροφορικής ΕΚΠΑ

Business Consulting
377 Syngrou Ave.
175 64 Athens


Δρακούλης Μαρτάκος
Επίκουρος Καθηγητής Τμήματος Πληροφορικής ΕΚΠΑ

Κτίρια Πληροφορικής, Πανεπιστιμιόπολη,
57 84



Learn about...

The Traditional Systems Life Cycle


Developing with Application Software

User Development

Outsourcing Information Systems

The Traditional Systems Life

Oldest method for building information systems

Still used today for complex medium/large
system projects

Traditional methodology for developing an IS that
partitions the systems development process into six
formal stages that must be completed sequentially with
a very formal division of labor between end users and
information systems specialists

Stages of the Systems Life

Project Definition

Systems Study





Limitations of the Life
Cycle Approach

Very resource intensive

Is inflexible and inhibits change

Ill suited to decision
oriented applications


Process of building an experimental system
quickly and inexpensively for demonstration and
evaluation so that end users can better
determine information requirements

It is an iterative process

Steps in Prototyping

Identify the user’s basic requirements

Develop a working prototype

Use the prototype

Revise and enhance the prototype

When no more iterations are required, the approved
prototype then becomes an operational prototype that
furnishes the final specifications for the application

Developing Systems with
Application Software Packages

Set of prewritten, precoded application software
programs that are commercially available for
sale or lease

Where functions are common to many companies

Where information systems resources for in
development are in short supply

When desktop microcomputer applications are being
developed for end

Advantages of Applications
Software Packages

Most of the design work has been
accomplished in advance

Fewer internal information systems
resources are necessary to support a
based system

Reduce some of the organizational
bottlenecks in the systems development
process (users have to accept it as is)

Disadvantages of Applications
Software Packages

Have not yet achieved the level of sophistication
and technical quality needed to produce
multipurpose packages

May not meet all of an organization’s

Extreme customization may result in the
package becoming unrecognizable

Vendor may stop providing support

Selecting Software

Request for Proposal (RFP)


Detailed list of
questions submitted to vendors of packaged
software or other computer services to
determine if the vendor’s product can meet the
organization’s specific requirements

Application Package
Development Cycle

Application Package Development Cycle
Identify Problem
Identify User Requirements
Identify Solution Alternatives
Identify Package Vendors
Evaluate Package vs. In-House Development
Evaluate Packages
Select Package
Systems Design
Tailor User Requirements to Package Features
Train Technical Staff on Package
Prepare Physical Design
Customize Package Design
Redesign Organizational Procedures
Programming, Testing, and Conversion
Install Package
Implement Package Modifications
Design Program Interfaces
Produce Documentation
Convert to Package System
Test the System
Train Users on Package
Production and Maintenance
Correct Problems
Install Updates or Enhancements to Package
User Development

The development of IS by end users with little or
no formal assistance from technical specialists

made possible by the 4th
generation software tools

users can access data, create reports, create web pages
without professional help

the role of IS specialist becomes supportive

systems can be created very rapidly

Advantages/Disadvantages of 4th
Generation Tools

Productivity gains of 300 to 500%

Capabilities remain limited

Require large amounts of computing resources

Slow response times for high volume processing

4th generation tools are most likely to create systems
rapidly and effectively when system builders lay the
appropriate groundwork

Benefits and Problems of
user Development

Improved requirements determination

User involvement and satisfaction

Control of the systems development process by users

Reduced application backlog

Insufficient review and analysis when user and analyst
functions are no longer separate

Lack of proper quality assurance standards and controls

Uncontrolled data

Proliferation of “private” information systems

Policies and Procedures to
Manage End
User Computing

Cost justification of end
user information systems projects

Hardware and software standards for user

wide standards for microcomputers, word processing
software, DBMS, graphics software, and query reporting tools

Quality assurance reviews, specifying whether only individual
and users or whether specialists from the information systems or
internal audit departments should review end
user developed

Controls for end
user developed applications covering testing,
documentation, accuracy, and completeness of input and
update, backup, recovery, and supervision

Outsourcing Information

The practice of contracting computer center operations,
telecommunication networks, or applications
development to external vendors


Loss of control

Service Quality

Vulnerability of Strategic Information



Making fixed costs variable

Freeing up human resources for other projects

Freeing up financial capital

When to Use Outsourcing

When there is only a limited opportunity for the firm to
distinguish itself competitively through a particular
information systems application or a series of

When outsourcing does not strip the company of the
technical know
how required for future information
systems innovation

When the firm’s existing information systems capabilities
are limited, ineffective, or technically inferior