Ch 8 - Systems Development 

• Participants in systems development:

  1. Development team:
  • Determines objectives of the information system
  • Delivers system that meets objectives
  1. Project:
  • Planned collection of activities that archives a goal
  1. Stakeholders:
  • People who benefit from a project
  1. Users:
  • People who interact regularly with the system
  1. system analyst:
  • Professional who specialises in analysing and designing business systems
  1. programmer:
  • Responsible for modifying or developing programs to satisfy user requirements

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• Individual systems developer: person who performs all of the systems development roles

• Individual users: acquire applications for both personal and professional use

• End-user systems development: describes any systems development project in which business managers and assume the primary effort

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• Information systems planning and aligning corporate and IS goals:

  • Information systems planning: translating strategic and organisational goals info systems development initiatives
  • Aligning goals and IS goals: critical for successful systems development effort

  

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• %%System Development Life Cycles%%:

  1. Traditional systems development life cycle:
  • Systems investigation: identifies problems and identities and considers them in a light of business goals
  • Systems analysis: studies existing systems and work processes to identify strengths, weaknesses, and opportunities for improvement
  • Systems design: defines how the information system will do what it must to obtain the problem’s solution
  • Systems implementation: creates or acquires various system components details in systems design, assembles them, and places new or modified system info operation
  • Systems maintenance and review: ensures the system operates as intended
  • Modifies the system so it continues to meet changing business needs

  

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2. Prototyping:

   • An iterative approach
   • Requirements and alternative solutions to the problem are identified and analysed
   • New solutions are designed, and a portion of the system is implemented
   • Rapid application development (RAD): employs tools, techniques, and methodologies designed to speed application development
   • Other approaches to rapid development:
   • Agile development
   • Extreme programming (XP)

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• Outsourcing and on-demand computing: Reasons for using outsourcing and on-demand computing approaches
  • Reduce costs
  • Obtain state-of-the-art technology
  • Eliminate staffing and personnel problems
  • Increases technological flexibility

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• Degree of Change: Continuous improvement projects vs. reengineering
  • Continuous improvement projects have a high degree of success
  • Reengineering projects have a high risk high benefit
• Managing change: essential to recognise and deal with existing or potential problems

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• Project Management Tools:

  • Project schedule: detailed description of what is to be done
  • Project milestone: critical date for completion of a major part of the project
  • Project deadline: date the entire project is set to be completed and operational

• Critical path: activities that, if delayed, would delay the entire project

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1. Object-oriented systems development: Combines logic of systems development life cycle with power of object-oriented modelling and programming

   • OOSD: identifies potential problems and opportunities

   • Defines what kind of system users require

   • Designing the program

   • Programming or modifying modules

   • Evaluation by users

   • Periodic review and modification

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• Feasibility analysis: Assesses:

  • Technical feasibility

  • Economic feasibility

  • Legal feasibility

  • Operational feasibility

  • Schedule feasibility

  • Object-oriented approach is used through all phases of system development

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• Investigation process: Initiated by a systems request form

• Systems analysis: The examination of existing systems

  • The systems investigation report summarises results of systems investigation

• Data modelling: accomplished through the use of entity-relationship (ER) diagram

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• Activity modelling:

  • Accomplished through the use of data-flow diagrams
  • DFDs: describe the activities that fulfils a business relationship or accomplish a business task

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• Requirements analysis: determines user, stakeholder, and organisational needs

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• System Design:
  • Logical design: describes functional requirements of a system
  • Physical design: specifies the characteristics of the system components necessary to put the logical design into action
  • Purpose of systems design: To prepare the detailed design needs for a new system or modifications to an existing system
  • Environmental design: Involves systems development efforts that slash power consumption and take less physical space
  • Request for proposal (RFP): document that specifies required resources such as hardware and software in detail
  • Purpose of systems implementation: To install a system and make everything, including users, ready for its operation
  • IS vendor: Company that offers hardware, software, telecommunications systems, databases, IS personnel, or other computer-related resources
  • Software: Can be purchased from external vendors or developed in house
  • Systems operation: The use of a new or modified system \n \n \n

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