Solving Business Problems with Information SystemsOverview of Systems Development

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Chapter 11

• Solving Business Problems with Information
  Systems--Overview of Systems Development

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DEVELOPING SOFTWARE

• Software that is built correctly can transform as
  the organization and its business transforms
• Software that effectively meets employee needs
  will help an organization become more productive
  and enhance decision making
• Software that does not meet employee needs may
  have a damaging effect on productivity and can
  even cause a business to fail

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DEVELOPING SOFTWARE

• As organizations reliance on software grows, so
  do the business-related consequences of software
  successes and failures including
• Increase or decrease revenue
• Repair or damage to brand reputation
• Prevent or incur liabilities
• Increase or decrease productivity

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How does an organization assure that new system
will be successful?

• get top management support
• involve as many end users as possible so they
  buy in
• keep end users up to date on new system
• work with corporate culture

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Strategic Planning important part of new system

• Businesses need way to analyze the direction they
  will take before they throw time, money, and
  personnel at a problem.
• You cant solve a problem until you know what the
  problem is.

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Systems Approach

• problem solving process to define information
  system problems and opportunities and develop
  solutions
• 7-step approach to analyze, design, and develop
  information systems is the Systems Development
  Life Cycle

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Why is this important for end users/knowledge
workers?

• Will define the future of IS in the organization
• Affects work productivity
• Affects morale
• Affects ability of organization to compete
• End users and knowledge workers are primary
  source of input as to what IS systems are needed

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THE SYSTEMS DEVELOPMENT LIFE CYCLE (SDLC)

• Systems development life cycle (SDLC) the
  overall process for developing information
  systems from planning and analysis through
  implementation and maintenance

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PHASE 1 PLANNING

• Planning phase involves establishing a
  high-level plan of the intended project and
  determining project goals
• Primary planning activities include
• Identify and select the system for development
• Assess project feasibility
• Develop the project plan

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Identify and Select the System for Development

• Organizations use different forms of evaluation
  criteria to determine which systems to develop
• Critical success factor (CSF) a factor that is
  critical to an organizations success

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Feasibility--determines if the proposed solution
is feasible and achievable from a financial,
technical, and organizational standpoint
Organizational Feasibility
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PHASE 2 ANALYSIS

• Analysis phase involves analyzing end-user
  business requirements and refining project goals
  into defined functions and operations of the
  intended system
• Primary analysis activities include
• Gather business requirements
• Create process diagrams
• Perform a buy vs. build analysis

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Gather Business Requirements

• Business requirements the detailed set of
  business requests that the system must meet in
  order to be successful
• Different ways to gather business requirements
• Joint application development (JAD) session
  where employees meet to define or review the
  business requirements for the system
• Interviews
• Questionnaires
• Observations
• Review business documents

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Perform a Buy vs. Build Analysis

• An organization faces two primary choices when
  deciding to develop an information system
• Buy the information system from a vendor
• Commercial off-the shelf (COTS) software
  package or solution that is purchased to support
  one or more business functions and information
  systems
• SCM, CRM, and ERP solutions are typically COTS
• Build the information system itself

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Perform a Buy vs. Build Analysis

• Organizations must consider the following when
  making a buy vs. build decision
• Are there any currently available products that
  fit the needs?
• Are there features that are not available and
  important enough to warrant the expense of
  in-house development?
• Can the organization customize or modify an
  existing COTS to fit its needs?
• Is there a justification to purchase or develop
  based on the acquisition cost?

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Step 3--Systems Design--Develop Specifications

• Purpose is to create a design that satisfies
  requirements
• User interfaces--screens, printed reports, forms,
  graphics
• Database specificationshow database needs to be
  set up
• Software specifications--software or programming
  logic to turn inputs into outputs
• Hardware and network specifications
• Personnel needed

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Design System Models

• Modeling the activity of drawing a graphical
  representation of a design
• Different modeling types include
• Graphical user interface (GUI)
• GUI screen design
• Data model
• Entity relationship diagram (ERD)

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Design System Models

• Sample entity relationship diagram (ERD)

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PHASE 4 DEVELOPMENT

• Development phase involves taking all of the
  detailed design documents from the design phase
  and transforming them into the actual system
• Primary development activities include
• Develop the IT infrastructure
• Develop the database and programs

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PHASE 5 TESTING

• Testing phase involves bringing all the project
  pieces together into a special testing
  environment to test for errors, bugs, and
  interoperability, in order to verify that the
  system meets all the business requirements
  defined in the analysis phase
• Primary testing activities include
• Write the test conditions
• Perform the system testing

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Perform the System Testing

• Different types of testing
• Unit testing tests each unit of code upon
  completion
• Application (or system) testing verifies that
  all units of code work together
• Integration testing exposes faults in the
  integration of software components or units
• Backup and recovery testing tests the ability
  of an application to be restarted after failure
• Documentation testing verifies instruction
  guides are helpful and accurate
• User acceptance testing (UAT) tests if a system
  satisfies its acceptance criteria

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PHASE 6 IMPLEMENTATION

• Implementation phase involves placing the
  system into production so users can begin to
  perform actual business operations with the
  system
• Primary implementation activities include
• Write detailed user documentation
• Determine implementation method
• Provide training for the system users

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Determine Implementation Method

• Four primary implementation methods
• Parallel implementation
• Plunge implementation
• Pilot implementation
• Phased implementation

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PHASE 7 MAINTENANCE

• Maintenance phase involves performing changes,
  corrections, additions, and upgrades to ensure
  the system continues to meet the business goals
• Primary maintenance activities include
• Build a help desk to support the system users
• Perform system maintenance
• Provide an environment to support system changes

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SOFTWARE PROBLEMS ARE BUSINESS PROBLEMS

• Primary reasons for project failure include
• Unclear or missing business requirements
• Skipping SDLC phases
• Failure to manage project scope
• Scope creep occurs when the scope increases
• Feature creep occurs when extra features are
  added
• Failure to manage project plan
• Changing technology

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SOFTWARE PROBLEMS ARE BUSINESS PROBLEMS

• Find errors early the later in the SDLC an error
  is found - the more expensive it is to fix

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SOFTWARE DEVELOPMENT METHODOLOGIES

• There are a number of different software
  development methodologies including
• Waterfall
• Rapid application development (RAD)
• Extreme programming
• Agile

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Waterfall Methodology

• Waterfall methodology a sequential,
  activity-based process in which each phase in the
  SDLC is performed sequentially from planning
  through implementation and maintenance

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Rapid Application Development Methodology (RAD)

• Rapid application development methodology (RAD)
  emphasizes extensive user involvement in the
  rapid and evolutionary construction of working
  prototypes of a system to accelerate the systems
  development process
• The prototype is an essential part of the
  analysis phase when using a RAD methodology
• Prototype a smaller-scale representation or
  working model of the users requirements or a
  proposed design for an information system

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Rapid Application Development Methodology (RAD)
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Extreme Programming Methodology

• Extreme programming (XP) methodology breaks a
  project into tiny phases, and developers cannot
  continue on to the next phase until the first
  phase is complete

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Agile Methodology

• Agile methodology a form of XP, aims for
  customer satisfaction through early and
  continuous delivery of useful software components
• Agile is similar to XP but with less focus on
  team coding and more on limiting project scope
• An agile project sets a minimum number of
  requirements and turns them into a deliverable
  product

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DEVELOPING SUCCESSFUL SOFTWARE

• Primary principles for successful agile software
  development include
• Slash the budget
• If it doesnt work, kill it
• Keep requirements to a minimum
• Test and deliver frequently
• Assign non-IT executives to software projects