9781423901785_PPT_ch12.ppt
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Management Information Systems, Sixth Edition Chapter 12: Systems Planning and Development
Objectives • Explain the importance of and steps in IT planning • Describe the systems development life cycle, which is the traditional approach to systems development • Explain the challenges involved in systems development • List the advantages and disadvantages of different system conversion strategies Management Information Systems, Sixth Edition 2
Objectives (continued) • Enumerate and explain the principles of agile systems development methods • Be able to contribute a meaningful set of requirements when serving on a project development team for a new or modified IS • Explain the concept of systems integration • Discuss whether IS professionals should be certified Management Information Systems, Sixth Edition 3
Planning Information Systems • Enterprise ISs are gaining in popularity • However, they: – Require a substantial investment – Carry a high risk in implementation • Successful integration of the system is vital – Must align IT strategies with the overall organization strategies • Careful planning of an IS implementation is necessary Management Information Systems, Sixth Edition 4
Steps in Planning Information Systems • IT planning includes several key steps: – Create a corporate and IT mission statement – Articulate the vision for IT within the organization – Create IT strategic and tactical plans – Create a plan for operations to achieve the mission and vision – Create a budget to ensure that resources are available to achieve the mission and vision Management Information Systems, Sixth Edition 5
Management Information Systems, Sixth Edition 6
Steps in Planning Information Systems (continued) • Mission statement: communicates the most important overarching goal of organization – Includes how the goals will be achieved • IS mission statement: describes the role of IT in the organization – Should be compatible with the organizational mission statement – Includes the ideal combination of hardware, software, and networking to support the mission Management Information Systems, Sixth Edition 7
Steps in Planning Information Systems (continued) • CIO develops a strategic plan for implementation of IT in the organization: – What technology will be used by employees, customers, and suppliers • Goals in the plan are broken down into objectives, such as: – Resources to be acquired or developed – Timetables for acquiring and implementing resources – Training Management Information Systems, Sixth Edition 8
Steps in Planning Information Systems (continued) • Objectives are broken down to operational details • IT planning is similar to planning of other resource acquisitions • Growing proportion of IT funds is spent on software in recent years – More purchasing and adapting of software – Less developing in-house software Management Information Systems, Sixth Edition 9
Management Information Systems, Sixth Edition 10
The Benefits of Standardization in Planning • One major goal and advantage of planning is standardization • Benefits include: – Cost savings: better bargaining power in purchasing and leasing hardware and software – Efficient training: a smaller variety of software reduces employee training needs – Efficient support: enables more staff specialization Management Information Systems, Sixth Edition 11
From Planning to Development • After planning, management must decide how to obtain the systems (usually software) • Approaches to systems development are the same for in-house or purchased systems • Two general approaches: – Systems development life cycle (SDLC), the traditional approach – Nontraditional methods, including agile methods • Prototyping: fast development of an application based on initial user requirements Management Information Systems, Sixth Edition 12
The Systems Development Life Cycle • Large ISs are conceived, planned, and developed within the systems development life cycle (SDLC) framework • Also known as waterfall development • Consists of four major sequential phases: – Analysis – Design – Implementation – Support Management Information Systems, Sixth Edition 13
Management Information Systems, Sixth Edition 14
Analysis • Systems analysis: a five-step process – Investigation – Technical feasibility study – Economic feasibility study – Operational feasibility study – Requirements definition Management Information Systems, Sixth Edition 15
Management Information Systems, Sixth Edition 16
Analysis (continued) • Investigation – Is a system really necessary? – Is the system, as conceived, feasible? • Small ad hoc team usually performs a preliminary investigation by interviewing employees • Feasibility studies: a larger analysis conducted after preliminary results indicate an IS is warranted Management Information Systems, Sixth Edition 17
Analysis (continued) • Technical feasibility study: – Determines if components exist or can be developed – Determines if the organization has adequate hardware • Economic feasibility study: – Determines if the new IS is economically justified – Cost/benefit analysis: spreadsheet showing all costs and benefits of the proposed system – Benefits must outweigh the costs over the life of the system Management Information Systems, Sixth Edition 18
Analysis (continued) • Return on investment (ROI): most accurate economic analysis – Calculates the difference between the stream of benefits and the stream of costs over the life of the system • May be difficult to justify the cost of a new IS because many benefits are intangible and cannot be quantified in dollar terms – Examples: business intelligence (BI) and knowledge management (KM) systems Management Information Systems, Sixth Edition 19
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Analysis (continued) • Operational feasibility study: – Determines how the new system will be used • Organizational culture: general tone of the corporate environment – Must determine the new system’s compatibility with the organizational culture • Requirements definition: details what the system should be able to do • System requirements: detail the functions and features expected from the new system Management Information Systems, Sixth Edition 21
Design • Design: the second phase in systems development • Systems design: includes three steps for devising the means to meet all the requirements – Description of the components – Construction – Testing • If purchasing a system: – Design phase determines how to adapt the existing software – Construction: actual changes in program code Management Information Systems, Sixth Edition 22
Management Information Systems, Sixth Edition 23
Design (continued) • Symbols are used to communicate ideas about data, processes, and information – Visual information can be grasped more quickly • Data flow diagram (DFD): describes the flow of data in a business operation using four symbols – External entities: individuals and groups external to the system (customers, employees, etc. ) – Processes: an event or events that affect data – Data store: any form of data at rest – Direction of data flow: indicates how data moves Management Information Systems, Sixth Edition 24
Management Information Systems, Sixth Edition 25
Design (continued) • The simplicity of a DFD is its advantage • DFD symbols are suitable for describing any IS, including noncomputer-based ISs • Can help pinpoint weaknesses: – Where processes can be automated – What is shared by different processes – What can be changed to strengthen the IS • A DFD cannot describe a system completely – Does not depict computations within processes or timing relationships among data flows Management Information Systems, Sixth Edition 26
Management Information Systems, Sixth Edition 27
Design (continued) • Unified modeling language (UML): de facto standard for visualizing, specifying, and documenting software • Helps developers communicate and logically validate desired features • Is independent of programming languages • Provides standard symbols and notations for depicting object-oriented elements Management Information Systems, Sixth Edition 28
Design (continued) • UML consists of diagrams: – Use case: an activity of the system in response to the user (an actor) – Class: describes class structure and contents – Interaction: describes interactions of objects and the sequence of their activities – State charts: indicate the states through which objects pass and their responses to stimuli – Activity: represents highly active states triggered by completion of other actions – Physical diagrams: high-level descriptions of software modules Management Information Systems, Sixth Edition 29
Management Information Systems, Sixth Edition 30
Design (continued) • Construction – Consists of mostly programming activities – May take months or years – Completed modules are tested via a walkthrough of the program logic or a simulation of actual program execution • System testing – Tests the entire integrated system, comparing results to the system requirements • Testing period often is the victim of schedule or budget compression, resulting in poor testing Management Information Systems, Sixth Edition 31
Implementation • Implementation: delivery of a new system – Consists of two steps: • Conversion • Training – Training may or may not precede conversion • Conversion: switching from the old system to the new system – Can be a very difficult time Management Information Systems, Sixth Edition 32
Implementation (continued) • Four basic conversion strategies: – Parallel conversion: the old system is used simultaneously with the new system at first – Phased conversion: breaks the new IS into modules and integrates one at a time • Reduces risk but delays some benefits – Cut-over conversion (or flash cut conversion): immediately replaces all modules • Risky but may be inexpensive – Pilot conversion: introduces the IS into one business unit at a time • Beta site: a site that tests the new system Management Information Systems, Sixth Edition 33
Management Information Systems, Sixth Edition 34
Support • Support: begins after delivery, and includes two responsibilities – Maintenance: postimplementation debugging, updates, and adding postponed features – User help • Maintenance comprises up to 80% of IS budgets • Support is the longest phase of the system life cycle • Effective maintenance requires good system documentation Management Information Systems, Sixth Edition 35
Agile Methods • Agile methods: alternative development methods – Treat software development as series of contacts with users – Goal: fast development of software – Improve software after user requests for modifications received • Agile methods use iterative programming Management Information Systems, Sixth Edition 36
Agile Methods (continued) • Popular agile methods include: – Extreme programming (XP) – Adaptive software development (ASD) – Lean development (LD) – Rational unified process (RUP) – Feature driven development (FDD) – Dynamic systems development method (DSDM) – Scrum – Crystal Management Information Systems, Sixth Edition 37
Management Information Systems, Sixth Edition 38
Agile Methods (continued) • Major advantage of agile methods: – Fast development of application software • Agile method risks include: – Analysis phase is limited or eliminated, increasing the risk of incompatibilities – More emphasis on programming, resulting in less documentation, which may make it difficult or impossible to make later modifications Management Information Systems, Sixth Edition 39
Agile Methods (continued) • Manifesto for Agile Software Development expresses these priorities: – Individuals and interactions over processes – Working software over comprehensive documentation – Customer collaboration over contract negotiation – Responding to change over following a plan • Agile methods aim to have light but sufficient development processes Management Information Systems, Sixth Edition 40
Agile Methods (continued) • User involvement is encouraged throughout the process • Modules are tested immediately after completion • Communication with users is informal • Extreme programming uses two programmers per module working on the same computer – Fosters constructive criticism and feedback • Domino’s Pizza successfully implemented XP method; Daimler. Chrysler did not Management Information Systems, Sixth Edition 41
When to Use Agile Methods • Agile methods are best used: – When a desired system is small • Analysis is less important • Requires a smaller investment of resources – For unstructured problems – For developing user interfaces – When users cannot specify all requirements at the start of the project • They may be unfamiliar with the technology • Requirements may be difficult to conceptualize Management Information Systems, Sixth Edition 42
When Not to Use Agile Methods • Do not use agile methods when: – The desired system is large or complex • System failure entails great financial loss – The desired system must interface with other systems • SDLC recommended for complex systems • Documentation is key for integration Management Information Systems, Sixth Edition 43
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Project Planning and Management Tools • Several tools exist to help plan and manage a development project, including IS projects • IBM’s Rational Portfolio Manager: – Helps plan investment in a new system and manage the development project and delivery • Primavera’s Pro. Sight: – Helps plan and manage application portfolios, resources, budgets, and compliance with government regulations Management Information Systems, Sixth Edition 45
Project Planning and Management Tools (continued) • Primavera’s e. Project: – Web-based tool that allows members and customers to define tasks and manage projects Management Information Systems, Sixth Edition 46
Systems Integration • Systems integration: – Examines the needs of entire organization – Produces a plan to combine disparate systems to allow data to flow between units • Some service companies specialize in systems integration • Integration is more challenging than development • Legacy systems may need to be interfaced with new systems Management Information Systems, Sixth Edition 47
Management Information Systems, Sixth Edition 48
Systems Integration (continued) • Systems integrators must be skilled in hardware and software • May be difficult to overcome hardware and software incompatibility issues between systems • Systems integration may span several organizations, requiring integration using telecommunications Management Information Systems, Sixth Edition 49
Summary • IT planning is important because of high investment costs and high risk in implementing enterprise applications • Standardization is an important part of IT planning • Systems development life cycle (SDLC) has welldefined phases: analysis, design, implementation, and support • Purpose of systems analysis is to determine what needs the system will satisfy Management Information Systems, Sixth Edition 50
Summary (continued) • Feasibility studies determine if a proposed system is possible and desirable • System requirements detail the features needed • Developers outline system components graphically using tools like UML • Unified Modeling Language (UML) is used to create model of desired system • Implementation includes training and conversion from the old system to the new system Management Information Systems, Sixth Edition 51
Summary (continued) • Support entails maintenance and satisfying changing needs • Agile methods are a popular alternative to traditional systems development life cycle • Tools help plan and manage development projects • Systems integration may be more complicated than systems development • Great responsibility of IS professionals results in the desirability of certification Management Information Systems, Sixth Edition 52