Title: Introduction: concepts and overview of systems development
1IMS5006 - Information Systems Development
Practices
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- Introduction concepts and overview of systems
development -
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2IMS5006 - Information Systems Development
Practices
- Lecturer Dr Peta Darke
- email peta.darke_at_sims.monash.edu.au
- phone 9903 2416
- office Room S7.13,
- level 7, 26 Sir John Monash Drive,
- Caulfield East
- Unit web page
- www.sims.monash.edu.au/subjects/ims5006.nsf
- Tutorials NO TUTORIALS IN WEEK 1
3Information 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 organisational context
4The systems development process
- The systems development lifecycle (SDLC)
- Planning (Feasibility)
- Systems analysis
- System design
- Implementation
- Maintenance
5Information 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)
6Information 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
7Information systems
- Need to understand the organisational context
- organisational culture
- "the system of shared beliefs and values that
develops within an organisation and guides the
behaviour of its members"
Schermerhorn et al (1994) - organisational structure, functions, procedures
- organisational management styles and policies
- Information systems involve people and
organisations, not just technology
8Dimensions 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
9the 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.
10the 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
11the 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
12information 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
13information 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
14information systems development methodologies
- the developers role
- e.g. the technical expert?
- the facilitator?
- the management change agent?
- the collaborative agent?
- the development process
- e.g. experts build a technical solution to
clearly defined problems (a series of products)
using prescribed tasks, objective view,
controlled process - OR a social process, build a human
activity system, multiple, subjective views,
complex and ill-structured problems,
socio-organisational context
15systems 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
16the 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
17the evolution of information systems development
methodologies
- changing role of information systems
- increasing complexity, size
- technological developments
- changing business environment global
economy, increasing competition, market shifts - support for less structured activities
- strategic business role of information
technology - non-operational level users
18the evolution of information systems development
methodologies
- criticisms of the traditional 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)
19the 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
20the 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
21the 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
22the 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
23the evolution of information systems development
methodologies
- the 1990s information systems development
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- 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
24Impact of change and new information technology
- effects of change
- - reactions to change
- - different procedures, work flows, skills
- - different organisational structures
- management of change
- - planning for change, impact assessment
- - incremental or radical change
- - guiding the change process
- evaluation of change
- - measuring the achievement of goals
- - assessing the results/impact
- - identifying constructive modifications
25System development methodologies
- sources of methodologies theory and practice
- - academic or research institutions
- - general usage
- - methodology vendors
- structure of methodologies
- - tightly-knit, prescriptive framework
- - flexible but integrated collection of
techniques - - a loose framework
26key problems for information systems development
- quality
- - systems development project failures
- - poor quality information systems
- productivity
- - larger, more complex systems
- - increasingly sophisticated technology
- - development backlog
27References
- 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