Introduction: concepts and overview of systems development

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IMS3230 - Information Systems Development
Practices

• Introduction concepts and overview of systems
  development

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IMS5006 - Information Systems Development
Practices

• Lecturer Dr Peta Darke
• email peta.darke_at_sims.monash.edu.au
• phone [phone]
• office Room S7.13,
• level7, 26 Sir John Monash Drive,
• Caulfield East
• Unit web page
• www.sims.monash.edu.au/subjects/ims3230.nsf
• Tutorials NO TUTORIALS IN WEEK 1

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Information systems development practice

• Concept and role of a systems development
  methodology
• Approaches to systems development
• The role of the systems analyst/developer
• Evaluate and compare methodologies
• The human and organisational context

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The systems development process

• The systems development lifecycle (SDLC)
• Planning (Feasibility)
• Systems analysis
• System design
• Implementation
• Maintenance

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Information system

• " A system which assembles, stores, processes and
  delivers information relevant to an organisation
  (or to society) in such a way that the
  information is accessible and useful to those who
  wish to use it, including managers, staff,
  clients and citizens. An information system is a
  human activity (social) system which may or may
  not involve the use of computer systems"
• Buckingham et al. (1987)
• (in Avison Fitzgerald 2003, p. 19)

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Information systems

• types of information systems
• transaction processing systems
• decision support systems
• expert systems
• executive information systems
• geographical information systems
• E-commerce systems
• multi-media systems
• differences in
• users
• size, scope
• complexity, certainty, familiarity

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Dimensions of information systems

• human, technological, organisational
• early on, technology was new, costly, and so
  technological failure was more likely
• failure of information system implementations now
  more likely due to human or organisational
  problems
• e.g. lack of planning,
• poor project management,
• poor training,
• inadequate change management,
• poor development methods and techniques,
• inadequate requirements identification and
  specification

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the evolution of information systems development
methodologies

• early computer system application development
  focused on the technology and on programming and
  technical skills rather than user and business
  needs
• systems developers were technically trained and
  skilled, and used rule-of-thumb and personal
  experience
• as computer use became more widespread
• a backlog of computer application requests
  developed
• existing applications increasingly required
  changes
• the changes made tended to have unexpected and
  undesirable effects.

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the evolution of information systems development
methodologies

• early 1960s no formalised methodologies
• basic data processing tasks
• batch processing, unsophisticated technology
• operational level, individual applications
• implementation by programmers
• maintenance / change problems
• poor documentation
• lack of standards, quality control

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the evolution of information systems development
methodologies

• the need for analysis and design activities and
  personnel in the development of information
  systems
• the need for more integrated information systems
  rather than piecemeal, one-off solutions
• the desirability of an accepted, standardised
  approach to development

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information systems development methodology

• A collection of procedures, techniques, tools
  and documentation aids which will help the
  systems developers in their efforts to implement
  a new information system. A methodology will
  consist of phases, themselves consisting of
  sub-phases, which will guide the systems
  developers in their choice of the techniques that
  might be appropriate at each stage of the project
  and also help them plan, manage, control and
  evaluate information systems projects
• Avison and Fitzgerald (2003) p 20

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information systems development methodologies

• Avison and Fitzgerald (1995)
• a methodology must have a philosophy
• - the nature of information systems
• - the nature of the developers role(s)
• - the nature of the development process
• e.g. what is the best system?
• the system which is the cheapest to run
• the system which allows automation of most of
  the business processes
• the system which is most acceptable to end users

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systems development methodologies (SDMs)

• Advantages of using a SDM
• Systematic approach to development
• Maintainable, well-documented systems
• Improved quality control and standards
• Focus for training
• Facilitates project management
• Consistency across projects
• Consistency across information systems
• Learning and experience in use
• Improved product and process

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the evolution of information systems development
methodologies

• Traditional waterfall SDLC approach
• feasibility study, system investigation, systems
  analysis, systems design, implementation, review
  and maintenance (NCC in the UK 1970s)
• a problem exists which can be solved by
  computerisation
• Advantages
• systematic, phases, documentation, standards,
  techniques
• Adequate response at first

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the evolution of information systems development
methodologies

• criticisms of the early SDLC approach
• user dissatisfaction focus on technical
  aspects
• lack of creative design
• piecemeal computerisation of applications
• emphasis on procedures and processes
• emphasis on "how"
• management and strategic needs ignored
• inflexibility
• low productivity (application backlog)

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the evolution of information systems development
methodologies

• structured approaches of the 1970s
• structured programming
• top-down design, "black box", basic logic
  constructs
• structured design
• top-down, design guidelines, incremental
  testing
• structured analysis
• functional decomposition, data flow diagrams,
• separation of logical and physical views

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the evolution of information systems development
methodologies

• data-oriented methodologies of the 1970s and
  1980s
• database technology, 4GLs, data analysis and data
  design
• data management data is a corporate resource
• need for integration of applications
• e.g. Information Engineering (James Martin)
• strategic role of data
• independence of data

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the evolution of information systems development
methodologies

• strategic planning approaches (mid 1970s and
  1980s)
• to align information systems development with
  business strategy
• to exploit information technology for strategic
  advantage
• to plan for IT and information systems
  development
• - identify business plans and goals, strategies,
  CSFs
• - evaluate current situation
• - develop information technology architecture
• - information architecture
• - applications architecture
• - technical architecture

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the evolution of information systems development
methodologies

• the 1980s information systems development
• prototyping
• CASE tools and development environments
• large database systems and 4GLs
• decentralisation
• user participation
• end user computing
• soft systems approaches

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the evolution of information systems development
methodologies

• the 1990s information systems development
• object-oriented approaches
• reusability in analysis and design activities
• outsourcing
• enterprise planning systems (ERP)
• business process re-engineering
• data warehouses
• the Internet and intranets and extranets
• multimedia

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References

• Prescribed text
• Avison, D.E. Fitzgerald, G. (2003).
• Information Systems Development
• Methodologies, Techniques and Tools. (3rd ed),
  McGraw-Hill, London.
• Chapters 1, 2, 6.5