Building Information Systems

1
Chapter 14

• Building Information Systems

2
Learning Objectives

• Explain the concept of a systems development life
  cycle (SDLC).
• Compare and contrast prototyping, rapid
  application development (RAD), joint application
  design (JAD), and traditional SDLC approaches to
  systems development.
• Identify advantages and disadvantages of
  object-oriented (OO) development.
• Describe component-based development

3
Learning Objectives (cont.)

• Evaluate alternatives to in-house systems
  development.
• Discuss the major strategies, methods, and tools
  for building e-commerce applications.
• Identify advantages and disadvantages of CASE
  tools.
• Describe alternative approaches to software
  process quality improvement.

4
Case Snap-On Sets up an EC Site

• Problem
• Snap-On, a tool and equipment maker in Washington
  state wanted to set up an e-commerce site and
  went for the in-house option.
• Solution
• Snap-On hired application service provider (ASP)
  OnLink Technologies to implement a catalog for
  the company's e-commerce site.
• Results
• The creation of an in-house ASP consulting
  service for Snap-On.
• Skill transferring to other departments and
  subsidiaries that want to put up catalogs on
  their own Web sites.

5
Systems Development Life Cycle

• Systems Development Life Cycle (SDLC) represents
  a set of general categories that show the major
  steps, over time, of an information systems
  development project.
• There is no universal, standardized version of
  the SDLC, but the phrase has two distinct
  meanings.
• An SDLC can be a general conceptual framework for
  all the activities involved in systems
  development or acquisition.
• An SDLC can also be a very structured and
  formalized design and development process.

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An Eight-Stage SDLC
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Stages 1 2

• Stage 1 Project Initiation
• Stage 2 Systems Analysis Feasibility Studies
• Systems Analysis - the investigation of the
  existing situation.
• Feasibility Studies - the major areas of
  feasibility investigation are
• Technology
• Economics
• Organizational factors
• Legal, ethical, and other constraints

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Stages 3 4

• Stage 3 Logical Analysis and Design
• Systems analysts determine 2 major aspects of the
  system
• what it needs to do
• how it will accomplish these functions.
• Logical Design the design of an IS from the
  users point of view.
• Physical Design -translates the abstract logical
  model into the specific technical design (the
  blueprints)
• Stage 4 Actual Acquisition or Development
• The logical design of the new system guides the
  actual development or acquisition

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Stages 5 6

• Stage 5 Implementation
• Approaches to conversion from a previous system
  include
• Parallel conversion
• Direct cutover
• Pilot conversion
• Phased (or modular) conversion
• Stage 6 Operation
• After a successful conversion, the system will
  operate for an indefinite period of time.

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Stages 7 8

• Stage 7 Post-audit Evaluation
• An organization should evaluate all its larger
  system projects after their completion.
• These post-audits introduce an additional element
  of discipline into the development process.
• Stage 8 Maintenance
• Every system needs two kinds of maintenance
• Fixing bugs
• Updating systems to accommodate changes in the
  environment

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Implementing SDLCs

• IS groups considering the implementation of a
  formal SDLC methodology should look for the
  following characteristics
• Minimal overhead
• Flexibility and responsiveness
• Concurrent tasks
• Focused analysis

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Alternatives to Conventional SDLCs

• Four Possibilities
• Prototyping
• Joint application design
• Rapid application development
• Object-oriented development

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Prototyping

• Instead of spending a lot of time producing very
  detailed specifications, the developers find out
  only what the users want.
• Developers quickly create a prototype.
• This contains portions of the system of most
  interest to the users, or is a small-scale
  working model of the entire system.
• After reviewing the prototype with the users, the
  developers refine extend it.
• This approach is also known as evolutionary
  development.

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Joint Application Design

• Joint application design (JAD) is a group-based
  method for collecting user requirements and
  creating system designs.
• JAD is most often used within the systems
  analysis and systems design stages of the SDLC.
• In contrast to the SDLC requirements analysis,
  JAD has a group meeting in which all users meet
  simultaneously with analysts.
• An electronic JAD session can be conducted
  offsite/online with technology support.
• JAD may not be an easy task for Web site design
  since in some cases the stakeholders may be
  outside of an organization.

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Rapid Application Development

• Rapid application development (RAD) methodologies
  and tools make it possible to develop systems
  faster, especially systems where the user
  interface is an important component.
• E.g., Blue Cross Blue Shield Develop an
  award-winning application using RAD.

• Typical RAD packages include the following
• GUI development environment
• Reusable components
• Code generator
• Programming language

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Rapid Application Development (cont.)
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Object-Oriented Development

• An object-oriented (OO) system begins not with
  the task to be performed, but with the aspects of
  the real world that must be modeled to perform
  that task.
• Object technology enables the development of
  purchasable, sharable, and reusable information
  assets (objects) existing in a worldwide network
  of interorganizational information systems.
• The techniques and notations that are
  incorporated into a standard object-oriented
  language are called unified modeling language or
  UML.
• The object-oriented approach is ideal for
  developing Web applications.

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Component-based Development

• Components are self-contained packages of
  functionality that have clearly defined, open
  interfaces with high-level application services.
• E.g., interface icons (small), online ordering (a
  business component)
• Components can be distributed dynamically for
  reuse across multiple applications and
  heterogeneous computing platforms.
• The major reasons for using components-based
  development are
• Code reusability, which make programming faster,
  with fewer errors.
• Support for heterogeneous computing
  infrastructure and platforms.
• Rapid assembly of new business applications
• Ability of an application to scale.

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Systems Developed Outside the ISD

• Many organizations are using approaches that
  shift the construction task from the IS
  department to others.
• Of the various ways of doing this, three are most
  common
• Let users build their own systems
• Outsource the entire systems development process
• Let end-users and/or the ISD use packages

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Trends Favoring End-User Development
The following list presents existing factors that
lead to higher levels of end-user development.

• Increasingly powerful desktop hardware
• Declining hardware costs
• Increasingly diverse software capabilities
• Increasingly computer-literate population

• Backlog of IS projects
• Development speed
• Business orientation
• Small applications
• Control
• Apparent cost savings

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Outsourcing

• Firms that provide outsourcing cite numerous
  benefits
• Hardware economies of scale
• Staffing economies of scale
• Specialization
• Tax benefits

• Outsourcing can also create problems for
  companies
• Limited economies of scale
• Staffing
• Lack of business expertise
• Contract problems
• Internal cost reduction opportunities

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External Acquisition of Software

• The choice between developing software in-house
  and purchasing existing software is called the
  make-or-buy decision.
• The initial cost of off-the-shelf software is
  often lower and the software should be of high
  quality, because many customers have used and
  helped debug it.
• However, buying off-the-shelf software may mean
  that an organization has to pay for features and
  functions that are not needed.

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External Acquisition of Software (cont.)

• The most prominent advantages of buying
  off-the-shelf software are
• On-time
• On-budget
• Full functionality

• The following outcomes are also important
• User acceptance
• Favorable costs-to-benefits ratio
• Low maintenance
• Scalability
• Integration with other systems
• Minimal negative cross-impacts
• Reusability

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Managerial Considerations

• The traditional SDLC approach often works well
  for large projects with well-defined
  requirements, where there is not a lot of time
  pressure.
• Prototyping requires effective management to make
  sure that the iterations of prototyping do not
  continue indefinitely.
• RAD may be less appropriate than conventional
  programming languages for larger projects, or
  those with a lot of real-time processing.
• JAD is easy for senior management to understand,
  yet it is difficult and expensive to get all
  people in the same place at the same time.

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Managerial Considerations (cont.)

• Object-Oriented development is becoming
  increasingly popular, but usage is limited by a
  shortage of personnel with OO skills.
• A component-based application architecture
  provides several business benefits, but the
  execution of component-based development requires
  special training and skill.
• End-user development is also a possibility for
  larger projects whose priorities are not high
  enough to lead to a timely response from the
  central IS unit.
• Outsourcing should always be considered by large
  and complex systems with a significant risk of
  failure, yet the disadvantages should be reviewed
  carefully.

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The Development of EC Applications
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The Development of EC Applications (cont.)

• Step 1 System Analysis
• Step 2 Select a Development Option
• Step 3 Installation, Connection, and More
• Step 4 Deployment
• Step 5 Operation and Maintenance

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Development Strategies for EC Applications

• Buy the EC Applications
• The following are the major criteria for
  consideration in buying e-commerce applications
• The functionalities of development packages
  criteria of choice
• User-friendliness
• Information requirements
• Hardware and software resources
• Installation
• Maintenance services
• Security
• Vendor quality
• Cost

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Development Strategies for EC Applications

• 2. Lease the EC Applications
• Leasing is advantageous in cases where extensive
  maintenance is required, or where the cost of
  buying is very high.
• Two ways to lease
• Lease the application from an outsourcer and
  install it on the companys premises.
• Lease from either an application service provider
  or a CSP.
• 3. Develop EC Applications In House Insourcing
• Build from scratch.
• Build from components.
• Enterprise application integration.

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Other Development Options

• Join An E-Marketplace
• Join An Auction or Reverse Auction Third-Party
  Site
• Joint Ventures
• Join a Consortium
• Hybrid Approach

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Application Service Provider

• An Application service provider (ASP) is an agent
  who assembles functionality needed by
  enterprises, and packages it with outsourced
  development, operation, maintenance, and other
  services.
• The essential difference between an ASP and an
  outsourcer is that an ASP will manage application
  servers in a centrally controlled location,
  rather than on a customers site.

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Benefits Risks of ASP Leasing
Type Benefit Potential Risk
Business Reduces the need to attract and retain skilled IT professionals. Loss of control and high level of dependence on ASP.
Enables company to concentrate on strategic use of IT. Inability of ASP to deliver quality of service lack of skills and experience.
Technical Fast and easy application deployment. Level of customization and legacy application integration offered by ASP may be insufficient.
Higher degree of application standardization. Reliability and speed of delivery due to bandwidth limitations.
Economic Low total cost of ownership. Pricing changes by ASP unpredictable for application updates and services.
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Criteria for Selecting an ASP Vendor

• Track record
• Scope of service
• Application data storage

• Support services
• Integration
• Database format portability

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Java Programming Language

• Java has established itself as the most important
  programming language for putting extra features
  into Web pages.
• Java is an object-oriented language.
• The Java Web page programs, called applets, need
  to be relatively small to avoid delays in
  transmitting them over the Internet.
• Prototyping is probably the most suitable
  approach for developing Java applets.

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CASE Tools

• Computer-aided software engineering (CASE) tools
  are marketed as individual items or in a set
  (toolkit) that automates various aspects of the
  development process.
• CASE can be used in two different ways
• To automate certain SDLC activities on a
  piecemeal basis.
• To provide an integrated (I-CASE) package for IS
  groups.
• The relatively high turnover rate among systems
  personnel creates problems for use of I-CASE
  systems as new employees will need to take the
  time to learn the integrated package.

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Software Quality

• The International Organization for
  Standardization (ISO) first published its quality
  standards in 1987, and then republished an
  updated version in 2000.
• The ISO allows organizations to use any SDLC that
  includes the following

• Testing and validation
• Acceptance
• Replication, delivery, and installation
• Maintenance

• Contract review
• Purchasers requirements specification
• Development planning
• Quality planning
• Design and implementation

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Project Planning

• Project planning provides an overall framework
  with which the systems development life cycle can
  be planned, scheduled, and controlled.
• Milestones, or checkpoints, are established to
  allow a periodic review of progress.

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Project Planning (cont.)

• Critical Path Method (CPM), PERT, and Gantt
  Charts.
•  These generic project management tools are
  suitable for systems development projects.
• Project Properties and Priorities
• The following five properties most significantly
  influence the overall nature of an IT project
• Predefined structure
• Stability of technology
• Size
• User proficiency
• Developer proficiency

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Managerial Issues

• Importance. Functional managers must participate
  in the development process and should understand
  all the phases.
• Ethical and legal issues. Developing systems
  across organizations and countries could result
  in problems in any phase of system development.

• Building interorganizational and international
  information systems can be very complicated.

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Managerial Issues (cont.)

• User involvement is important.
• Traditional approaches vs. prototyping.
• Tool use by developers.

• Quality assurance vs. schedules.
• Behavior problems.
• Perpetual development.