information systems overview (cois 20024) lecture: week 10 developing information systems...
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Information Systems OverviewInformation Systems Overview(COIS 20024)(COIS 20024)
Lecture: Week 10
Developing Information Systems
(Information Systems Development & Management)
24-SEP-2001
Daniel Pun, School of Computing & Information Systems, CQU, Australia 2
Week 10: ResourcesWeek 10: ResourcesWeek 10: ResourcesWeek 10: Resources
Study Guide Module 10: Developing Information Systems
Textbook Chapter 10: Developing E-Business Solutions
Resource Materials
Reading 10-1 & 10-2
24-SEP-2001
Daniel Pun, School of Computing & Information Systems, CQU, Australia 3
ObjectivesObjectivesObjectivesObjectives
Identify & describe the stages of the traditional IS development life cycle
Discuss what is involved in SA & SD Explain how prototyping changes the
traditional IS development activities Describe how CASE tools are used in systems
development Explain why & how users should be involved
in IS analysis & implementation
24-SEP-2001
Daniel Pun, School of Computing & Information Systems, CQU, Australia 4
Objectives Objectives (cont’d)(cont’d)Objectives Objectives (cont’d)(cont’d)
Discuss what is involved in IS implementation Discuss the evaluation factors that should be
considered in evaluating the acquisition of H/W, S/W, and IS services
Identify some of the challenges involved in the implementation process for managing technological change
24-SEP-2001
Daniel Pun, School of Computing & Information Systems, CQU, Australia 5
ObjectivesObjectivesObjectivesObjectives
Identify & describe the stages of the traditional IS development life cycle
Discuss what is involved in SA & SD Explain how prototyping changes the
traditional IS development activities Describe how CASE tools are used in systems
development Explain why & how users should be involved
in IS analysis & implementation
24-SEP-2001
Daniel Pun, School of Computing & Information Systems, CQU, Australia 6
Designthe
Solution
Designthe
Solution
Definethe
Problem
Definethe
Problem
DevelopAlternativeSolutions
DevelopAlternativeSolutions
Selectthe
Solution
Selectthe
Solution
Implementthe
Solution
Implementthe
Solution
Mo
nit
or
and
E
valu
ate
Res
ult
s
Systems Approach to Problem SolvingSystems Approach to Problem SolvingSystems Approach to Problem SolvingSystems Approach to Problem Solving
24-SEP-2001
Daniel Pun, School of Computing & Information Systems, CQU, Australia 7
The systems approach views a business process as a system that has 5 components: input, process, output, feedback & control. The systems approach to problem solving uses the systems orientation to conceptualize the nature of the problem. Under the systems orientation, all elements of a problem interact with one another. Consequently, the systems approach considers each "step" to influence & provide feedback on every other step.
Systems Approach to Problem Solving Systems Approach to Problem Solving (cont’d)(cont’d)Systems Approach to Problem Solving Systems Approach to Problem Solving (cont’d)(cont’d)
24-SEP-2001
Daniel Pun, School of Computing & Information Systems, CQU, Australia 8
The traditional IS development cycle is based upon the stages in the systems approach to problem solving, where each step is interdependent on the previous step.
Using the systems approach to develop IS solutions can be viewed as a multistep process called the information systems development cycle, also known as the systems development life cycle (SDLC). The SDLC is composed of five steps.
Traditional IS Development Life CycleTraditional IS Development Life CycleTraditional IS Development Life CycleTraditional IS Development Life Cycle
24-SEP-2001
Daniel Pun, School of Computing & Information Systems, CQU, Australia 9
Systems ImplementationProduct:
Operational System
Systems ImplementationProduct:
Operational System
Systems InvestigationProduct:
Feasibility Study
Systems InvestigationProduct:
Feasibility Study
Systems AnalysisProduct:
Functional Requirements
Systems AnalysisProduct:
Functional Requirements
Systems DesignProduct:
System Specifications
Systems DesignProduct:
System Specifications
Systems MaintenanceProduct:
Improved System
Systems MaintenanceProduct:
Improved System
Understand theBusinessProblem orOpportunity
Develop anInformationSystemSolution
Implementthe InformationSystemSolution
Traditional IS Development Life Cycle Traditional IS Development Life Cycle (cont’d)(cont’d)Traditional IS Development Life Cycle Traditional IS Development Life Cycle (cont’d)(cont’d)
24-SEP-2001
Daniel Pun, School of Computing & Information Systems, CQU, Australia 10
Systems Investigation: This stage may begin with a formal information systems planning process to help sort out choices from many opportunities. Typically, due to the expense associated with IS development this stage includes a cost/benefit analysis as part of a feasibility study.
Traditional IS Development Life Cycle Traditional IS Development Life Cycle (cont’d)(cont’d)Traditional IS Development Life Cycle Traditional IS Development Life Cycle (cont’d)(cont’d)
24-SEP-2001
Daniel Pun, School of Computing & Information Systems, CQU, Australia 11
Systems Analysis: This stage includes an analysis of the info needs of end users, the organisational environment, and any system currently used to develop the functional requirements of a new system.
Systems Design: This stage develops specifications for the H/W, S/W, people, network, & data resources of the system. The info products the system is expected to produce are also designated.
Traditional IS Development Life Cycle Traditional IS Development Life Cycle (cont’d)(cont’d)Traditional IS Development Life Cycle Traditional IS Development Life Cycle (cont’d)(cont’d)
24-SEP-2001
Daniel Pun, School of Computing & Information Systems, CQU, Australia 12
Systems Implementation: Here the organisation develops or acquires the H/W & S/W needed to implement the system design. Testing of the system & training of people to operate & use the system are also part of this stage. Finally, the organisation converts to the new system.
Systems Maintenance: In this stage, management uses a postimplementation review process to monitor, evaluate, & modify the system as needed.
Traditional IS Development Life Cycle Traditional IS Development Life Cycle (cont’d)(cont’d)Traditional IS Development Life Cycle Traditional IS Development Life Cycle (cont’d)(cont’d)
24-SEP-2001
Daniel Pun, School of Computing & Information Systems, CQU, Australia 13
When using the SDLC: All the activities involved are highly
related and interdependent Several developmental activities can
occur at the same time Different parts of a development project
can be at different stages of the development cycle
May recycle back at any time to repeat previous activities in order to modify & improve a system being developed
Traditional IS Development Life Cycle Traditional IS Development Life Cycle (cont’d)(cont’d)Traditional IS Development Life Cycle Traditional IS Development Life Cycle (cont’d)(cont’d)
24-SEP-2001
Daniel Pun, School of Computing & Information Systems, CQU, Australia 14
Objectives Objectives (cont’d)(cont’d)Objectives Objectives (cont’d)(cont’d)
Identify & describe the stages of the traditional IS development life cycle
Discuss what is involved in SA & SD Explain how prototyping changes the
traditional IS development activities Describe how CASE tools are used in systems
development Explain why & how users should be involved
in IS analysis & implementation
24-SEP-2001
Daniel Pun, School of Computing & Information Systems, CQU, Australia 15
Systems Analysis (SA) describes what a system should do to meet the information needs of users
Systems Design (SD) specifies how the system will accomplish this objective
SA & SDSA & SDSA & SDSA & SD
24-SEP-2001
Daniel Pun, School of Computing & Information Systems, CQU, Australia 16
SA is an in-depth study of end user info needs, which produces functional requirements that are used as the basis for the design of a new IS. SA traditionally involves a detailed study of:
The info needs of the company & the end users The activities, resources, & products of any
present IS being used The IS capabilities required to meet the info
needs of end users, and those of other E-business stakeholders that may use the system
Systems Analysis (SA)Systems Analysis (SA)Systems Analysis (SA)Systems Analysis (SA)
24-SEP-2001
Daniel Pun, School of Computing & Information Systems, CQU, Australia 17
KeyAreas ofSystemsAnalysis
OrganizationalOrganizational
FunctionalRequirements
FunctionalRequirements
PresentSystemPresentSystem
SA SA (cont’d)(cont’d)SA SA (cont’d)(cont’d)
24-SEP-2001
Daniel Pun, School of Computing & Information Systems, CQU, Australia 18
Organisational analysis involves evaluating the organisational & environmental systems & subsystems involved in any situation. SA traditionally involves a detailed study of the organisations:
Environment Management structure People Business activities Environmental systems it deals with Current IS
SA SA (cont’d)(cont’d)SA SA (cont’d)(cont’d)
24-SEP-2001
Daniel Pun, School of Computing & Information Systems, CQU, Australia 19
Before designing a new system, a detailed analysis of the current system (manual or automated) must be completed. An analysis of the present system involves analyzing activities, resources, and the products. We must analyse how the present system uses:
H/W, S/W, people resources to convert data resources into info products, such as reports & displays
Document how the info activities of input, processing, output, storage, & control are being accomplished
SA SA (cont’d)(cont’d)SA SA (cont’d)(cont’d)
24-SEP-2001
Daniel Pun, School of Computing & Information Systems, CQU, Australia 20
Functional Requirements Analysis: This step of SA is one of the most difficult. Steps involve:
Working as a team with IS analysts & end users to determine specific business info needs
Determining the info processing capabilities required for each system activity (input, processing, output, storage, & control) to meet the info needs. Goal is to identify What should be done NOT how to do it
Developing functional requirements (info requirements that are not tied to the h/w, s/w, network, data, & people resources that end users presently use or might use in the new system)
SA SA (cont’d)(cont’d)SA SA (cont’d)(cont’d)
24-SEP-2001
Daniel Pun, School of Computing & Information Systems, CQU, Australia 21
SD consists of design activities, which produce systems specifications satisfying the functional requirements developed in the SA stage. These specifications are used as the basis for: S/W development H/W acquisition System testing Other activities of the implementation
stage
Systems Design (SD)Systems Design (SD)Systems Design (SD)Systems Design (SD)
24-SEP-2001
Daniel Pun, School of Computing & Information Systems, CQU, Australia 22
DataDesignData
Design
UserInterfaceDesign
UserInterfaceDesign
ProcessDesign
ProcessDesign
Screen, Form, Reportand Dialog Design
Data ElementStructure Design
Program andProcedure Design
SD SD (cont’d)(cont’d)SD SD (cont’d)(cont’d)
24-SEP-2001
Daniel Pun, School of Computing & Information Systems, CQU, Australia 23
SD can be viewed as the design of three major products, or deliverables, that should result from the design stage. These activities include: User interface design Data design Process design
SD SD (cont’d)(cont’d)SD SD (cont’d)(cont’d)
24-SEP-2001
Daniel Pun, School of Computing & Information Systems, CQU, Australia 24
Objectives Objectives (cont’d)(cont’d)Objectives Objectives (cont’d)(cont’d)
Identify & describe the stages of the traditional IS development life cycle
Discuss what is involved in SA & SD Explain how prototyping changes the
traditional IS development activities Describe how CASE tools are used in systems
development Explain why & how users should be involved
in IS analysis & implementation
24-SEP-2001
Daniel Pun, School of Computing & Information Systems, CQU, Australia 25
Prototyping is the rapid development & testing of working models, or prototypes, of new applications in an interactive, iterative process involving both IS specialists & business professionals.
Prototyping makes the development process faster & easier for IS specialists & business professionals.
PrototypingPrototypingPrototypingPrototyping
24-SEP-2001
Daniel Pun, School of Computing & Information Systems, CQU, Australia 26
Prototyping makes the development process faster & easier, especially for projects where end user requirements are hard to define. Thus, prototyping is sometimes called rapid application design (RAD).
Prototyping has also opened up the application development process to end-users because it simplifies & accelerates systems design. These developments are changing the roles of end users & IS specialists in systems development.
Prototyping Prototyping (cont’d)(cont’d)Prototyping Prototyping (cont’d)(cont’d)
24-SEP-2001
Daniel Pun, School of Computing & Information Systems, CQU, Australia 27
Typically, large E-business systems still require using the traditional systems development approach, but parts of such systems can frequently be prototyped.
A prototype of a business application needed by an end user is developed quickly using a variety of application development software tools. The prototype system is then repeatedly refined until it is acceptable.
Prototyping is an iterative, interactive process that combines steps of the traditional systems development cycle, & allows the rapid development & testing of a working model.
Prototyping Prototyping (cont’d)(cont’d)Prototyping Prototyping (cont’d)(cont’d)
24-SEP-2001
Daniel Pun, School of Computing & Information Systems, CQU, Australia 28
Use and Maintainthe Accepted
System
Use and Maintainthe Accepted
System
Identify an EndUser's Information
Requirements
Identify an EndUser's Information
Requirements
DevelopInformation System
Prototypes
DevelopInformation System
Prototypes
Revise the Prototypesto Better Meet EndUser Requirements
Revise the Prototypesto Better Meet EndUser Requirements
PrototypingCycle
MaintenanceCycle
Prototyping ProcessPrototyping ProcessPrototyping ProcessPrototyping Process
24-SEP-2001
Daniel Pun, School of Computing & Information Systems, CQU, Australia 29
Identify Requirements: End users identify their info needs & assess the feasibility of several alternative info system solutions.
Develop Prototype: End users and/or systems analysts use application development packages to interactively design & test prototypes of IS components that meet end user info needs.
Revise Prototype: During this stage, the IS prototypes are used, evaluated, & modified repeatedly until end users find them acceptable.
Use & Maintain: The accepted system can be modified easily since most system documentation is stored on disk.
Prototyping Process Prototyping Process (cont’d)(cont’d)Prototyping Process Prototyping Process (cont’d)(cont’d)
24-SEP-2001
Daniel Pun, School of Computing & Information Systems, CQU, Australia 30
Objectives Objectives (cont’d)(cont’d)Objectives Objectives (cont’d)(cont’d)
Identify & describe the stages of the traditional IS development life cycle
Discuss what is involved in SA & SD Explain how prototyping changes the
traditional IS development activities Describe how CASE tools are used in systems
development Explain why & how users should be involved
in IS analysis & implementation
24-SEP-2001
Daniel Pun, School of Computing & Information Systems, CQU, Australia 31
The traditional systems development life cycle (SDLC) process has often been too inflexible, time-consuming, & expensive for many organizations to utilise. To overcome some of the shortfalls of the SDLC, Computer-Aided Systems Engineering (CASE) has emerged. CASE involves using software packages called CASE tools, to perform many of the activities of the SDLC.
CASE ToolsCASE ToolsCASE ToolsCASE Tools
24-SEP-2001
Daniel Pun, School of Computing & Information Systems, CQU, Australia 32
CASE software packages are available to help do:
Business planning Project management User interface design Database design Software development
CASE Tools CASE Tools (cont’d)(cont’d)CASE Tools CASE Tools (cont’d)(cont’d)
24-SEP-2001
Daniel Pun, School of Computing & Information Systems, CQU, Australia 33
Many CASE packages -- help to automate the use of graphics tools
such as flowcharts and data flow diagrams. provide tools for the front end of the
systems development life cycle (planning, analysis, & design) & the back end (implementation & maintenance).
include a system repository component that expands the role of the data dictionary as a catalog of data definitions.
CASE Tools CASE Tools (cont’d)(cont’d)CASE Tools CASE Tools (cont’d)(cont’d)
24-SEP-2001
Daniel Pun, School of Computing & Information Systems, CQU, Australia 34
A system repository provides systems analysts with computer-aided data descriptions & other cataloguing facilities, beginning with their systems planning & systems analysis activities, & continuing through the design, implementation, & maintenance of the system. Thus, the repository has become a database for all the details of a system generated with other systems development tools.
CASE Tools CASE Tools (cont’d)(cont’d)CASE Tools CASE Tools (cont’d)(cont’d)
24-SEP-2001
Daniel Pun, School of Computing & Information Systems, CQU, Australia 35
Integrated CASE tools (I-CASE) can assist all of the stages of systems development.
Some CASE tools support -- Joint application design (JAD): a group of
systems analysts, programmers, & end users can jointly & interactively design new applications
Backward engineering: allow systems analysts to inspect the logic of a program code for old applications & convert it automatically into more efficient programs that significantly improve system effectiveness.
CASE Tools CASE Tools (cont’d)(cont’d)CASE Tools CASE Tools (cont’d)(cont’d)
24-SEP-2001
Daniel Pun, School of Computing & Information Systems, CQU, Australia 36
Objectives Objectives (cont’d)(cont’d)Objectives Objectives (cont’d)(cont’d)
Identify & describe the stages of the traditional IS development life cycle
Discuss what is involved in SA & SD Explain how prototyping changes the
traditional IS development activities Describe how CASE tools are used in systems
development Explain why & how users should be involved
in IS analysis & implementation
24-SEP-2001
Daniel Pun, School of Computing & Information Systems, CQU, Australia 37
Direct end user participation in systems development projects before a system is implemented is especially important to reducing the potential for end user resistance. This involvement helps ensure that end users “assume ownership” of a system, and that its design meets their needs.
End User InvolvementEnd User InvolvementEnd User InvolvementEnd User Involvement
24-SEP-2001
Daniel Pun, School of Computing & Information Systems, CQU, Australia 38
Objectives Objectives (cont’d)(cont’d)Objectives Objectives (cont’d)(cont’d)
Discuss what is involved in IS implementation Discuss the evaluation factors that should be
considered in evaluating the acquisition of H/W, S/W, and IS services
Identify some of the challenges involved in the implementation process for managing technological change
24-SEP-2001
Daniel Pun, School of Computing & Information Systems, CQU, Australia 39
ConversionConversionSystemDocu-
mentation
SystemDocu-
mentation
End UserTrainingEnd UserTraining
Developmentand
Modification
Developmentand
ModificationAcquisitionAcquisition
ImplementationActivities
ImplementationActivities
SystemTestingSystemTesting
IS ImplementationIS ImplementationIS ImplementationIS Implementation
24-SEP-2001
Daniel Pun, School of Computing & Information Systems, CQU, Australia 40
The implementation process involves developing the IS into an operational system for end users. Key activities include:
Acquisition of Hardware, Software, & Services: Some very large organisations purchase proprietary H/W & S/W solutions. An increasing number of companies can purchase off-the-shelf H/W & S/W from original equipment manufacturers or resellers.
IS Implementation IS Implementation (cont’d)(cont’d)IS Implementation IS Implementation (cont’d)(cont’d)
24-SEP-2001
Daniel Pun, School of Computing & Information Systems, CQU, Australia 41
Software Development or Modification: Some companies write their own software in-house. Even for those firms that buy software off-the-shelf, modification is often necessary (indeed, the flexibility to modify software is built in to most application programs).
System Testing: Involves testing website or application performance. It may involve such activities as testing & debugging S/W & testing new H/W.
End User Training: This is a vital activity. Provisions & resources for training end users on the new system must be identified & allocated.
IS Implementation IS Implementation (cont’d)(cont’d)IS Implementation IS Implementation (cont’d)(cont’d)
24-SEP-2001
Daniel Pun, School of Computing & Information Systems, CQU, Australia 42
System Documentation: How to use & maintain the system must be provided in the form of manuals and, increasingly, online help. In addition, a detailed record of the system’s design is essential for future problem diagnostics or making changes. This effort is simplified through the use of CASE tools.
Conversion: This involves the actual logistics of switching to the new system.
IS Implementation IS Implementation (cont’d)(cont’d)IS Implementation IS Implementation (cont’d)(cont’d)
24-SEP-2001
Daniel Pun, School of Computing & Information Systems, CQU, Australia 43
Objectives Objectives (cont’d)(cont’d)Objectives Objectives (cont’d)(cont’d)
Discuss what is involved in IS implementation Discuss the evaluation factors that should be
considered in evaluating the acquisition of H/W, S/W, and IS services
Identify some of the challenges involved in the implementation process for managing technological change
24-SEP-2001
Daniel Pun, School of Computing & Information Systems, CQU, Australia 44
In today’s E-Business environment, acquisition of hardware, software, and IS services is an important part of E-application development. How should companies make such acquisition choices? What process should they use for selecting vendors?
EvaluatingEvaluatingEvaluatingEvaluating
24-SEP-2001
Daniel Pun, School of Computing & Information Systems, CQU, Australia 45
Hardware Hardware Evaluation Evaluation FactorsFactors
Performance Cost Reliability Compatibility Technology Connectivity Scalability Support Software
Software Software Evaluation Evaluation
FactorsFactors Quality Flexibility Security Connectivity Language Documentation Hardware Efficiency
Evaluation Factors: H/W & S/WEvaluation Factors: H/W & S/WEvaluation Factors: H/W & S/WEvaluation Factors: H/W & S/W
24-SEP-2001
Daniel Pun, School of Computing & Information Systems, CQU, Australia 46
When acquiring IS services, other evaluation factors need to be considered. These include:
Past Performance: Referrals from past customers is essential.
Business Position: Is the vendor financially strong, with good industry prospects?
Service & Capabilities: What kind of services can they offer? What kind of equipment do they have available?
Accessibility: Does the vendor provide local or regional support?
Maintenance and Guarantees: Will they maintain their product? Are there warranties?
Evaluation Factors: IS ServicesEvaluation Factors: IS ServicesEvaluation Factors: IS ServicesEvaluation Factors: IS Services
24-SEP-2001
Daniel Pun, School of Computing & Information Systems, CQU, Australia 47
Objectives Objectives (cont’d)(cont’d)Objectives Objectives (cont’d)(cont’d)
Discuss what is involved in IS implementation Discuss the evaluation factors that should be
considered in evaluating the acquisition of H/W, S/W, and IS services
Identify some of the challenges involved in the implementation process for managing technological change
24-SEP-2001
Daniel Pun, School of Computing & Information Systems, CQU, Australia 48
Any new way of doing things generates some resistance by the people affected. Thus, implementation of new E-Business technologies can generate fear & resistance to change by employees & managers. To reduce user resistance to change, change must be managed.
Challenges for Managing Technological ChangeChallenges for Managing Technological ChangeChallenges for Managing Technological ChangeChallenges for Managing Technological Change
24-SEP-2001
Daniel Pun, School of Computing & Information Systems, CQU, Australia 49
ChangeManagement
Measurementand
Rewards
OrganizationalDesign
CoreCompetenciesDevelopment
Educate andTrain
UserInvolvement
Challenges for Managing Technological Change Challenges for Managing Technological Change (cont’d)(cont’d)Challenges for Managing Technological Change Challenges for Managing Technological Change (cont’d)(cont’d)
24-SEP-2001
Daniel Pun, School of Computing & Information Systems, CQU, Australia 50
Change management involves managing the people & the processes of organisational change. This can include:
Educating employees on the need for change
Recruiting & training employees in core competencies
Developing innovative ways to measure, motivate, & reward performance
Challenges for Managing Technological Change Challenges for Managing Technological Change (cont’d)(cont’d)Challenges for Managing Technological Change Challenges for Managing Technological Change (cont’d)(cont’d)
24-SEP-2001
Daniel Pun, School of Computing & Information Systems, CQU, Australia 51
Analysing the impact of change before committing it
Encouraging direct user involvement in organisational change & system development efforts
Making change part of the organisational culture (Develop a change action plan, Develop change teams & change sponsors)
Working within the company culture not around it
Challenges for Managing Technological Change Challenges for Managing Technological Change (cont’d)(cont’d)Challenges for Managing Technological Change Challenges for Managing Technological Change (cont’d)(cont’d)
24-SEP-2001
Daniel Pun, School of Computing & Information Systems, CQU, Australia 52
Information Systems Development & Management
:
Managing Information Systems
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