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This chapter covers the phases of the systems development life cycle, the individuals involved, planning techniques, feasibility determination, and managing system changes.
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HAPTER 18 Introduction to Systems Development and Systems Analysis
INTRODUCTION • Questions to be addressed in this chapter include: • What are the phases in the systems development life cycle? • Who are the individuals involved in systems development? • What techniques are used to plan the development of a system? • How do you determine whether a particular system is feasible? • How do people respond to systems changes, and how can dysfunctional behavior be minimized?
INTRODUCTION • As the environment, technology, and competition change, an information system must continually undergo changes. • These changes range from minor adjustments to major overhauls. • Occasionally, the old system is scrapped and replaced.
INTRODUCTION • Companies change their systems for a variety of reasons: • To respond to changes in user needs or business needs. • To take advantage of or respond to technology changes. • To accommodate improvements in their business process. • To gain a competitive advantage and/or lower costs. • To increase productivity. • To accommodate growth. • To accommodate downsizing or distribute decision making • To integrate incompatible systems. • To replace a system that is aged and unstable.
INTRODUCTION • Developing quality, error-free software is difficult, expensive, and time-consuming. • Projects tend to deliver less than expected and consume more time and money. • A KPMG survey found that 35% of all major information systems projects were classified as runaways—hopelessly incomplete and over budget. • Major cause of runaways: Skimping on systems development processes. • Omitting basic systems development steps becomes tempting but may lead to disaster as developers create well-structured systems that fail to meet user needs or solve business problems.
INTRODUCTION • This chapter discusses five topics: • Systems development life cycle • Planning activities during the systems development life cycle • Feasibility analysis • Behavioral aspects of change • Systems analysis
SYSTEMS DEVELOPMENT LIFE CYCLE • Whether systems changes are major or minor, most companies go through a systems development life cycle. • In this section, we discuss the steps in the cycle and the people involved.
SYSTEMS DEVELOPMENT LIFE CYCLE • The five stages in the systems development life cycle are: • Systems analysis • Conceptual design • Physical design • Implementation and conversion • Operation and maintenance
SYSTEMS DEVELOPMENT LIFE CYCLE • The five stages in the systems development life cycle are: • Systems analysis • Conceptual design • Physical design • Implementation and conversion • Operation and maintenance
SYSTEMS DEVELOPMENT LIFE CYCLE • As organizations grow and change, they may need more or better information. • Systems analysis is the first step. It includes: • Initial investigation • Involves gathering the information needed to buy or develop a new system and determining whether it is a priority.
SYSTEMS DEVELOPMENT LIFE CYCLE • As organizations grow and change, they may need more or better information. • Systems analysis is the first step. It includes: • Initial investigation • Systems survey • If the system is a priority, survey the existing system to define the nature and scope of the project and identify the strengths and weaknesses of the system.
SYSTEMS DEVELOPMENT LIFE CYCLE • As organizations grow and change, they may need more or better information. • Systems analysis is the first step. It includes: • Initial investigation • Systems survey • Feasibility study • Involves an in-depth study of the proposed system to determine whether it’s feasible.
SYSTEMS DEVELOPMENT LIFE CYCLE • As organizations grow and change, they may need more or better information. • Systems analysis is the first step. It includes: • Initial investigation • Systems survey • Feasibility study • Determination of information needs and system requirements • Involves finding out and documenting what users and management need. • This is the most important aspect of systems analysis.
SYSTEMS DEVELOPMENT LIFE CYCLE • As organizations grow and change, they may need more or better information. • Systems analysis is the first step. It includes: • Initial investigation • Systems survey • Feasibility study • Determination of information needs and system requirements • Delivery of systems requirements • Involves preparation of a report summarizing the systems analysis work. • This report is submitted to the information systems steering committee.
SYSTEMS DEVELOPMENT LIFE CYCLE • The five stages in the systems development life cycle are: • Systems analysis • Conceptual design • Physical design • Implementation and conversion • Operation and maintenance
SYSTEMS DEVELOPMENT LIFE CYCLE • In the conceptual design phase, the company decides how to meet user needs. • Tasks in this phase include: • Identify and evaluate design alternatives • Possibilities include: • Buying software • Developing in-house • Outsourcing
SYSTEMS DEVELOPMENT LIFE CYCLE • In the conceptual design phase, the company decides how to meet user needs. • Tasks in this phase include: • Identify and evaluate design alternatives • Develop design specifications • Involves writing up details of what the system is to accomplish and how it is to be controlled and developed.
SYSTEMS DEVELOPMENT LIFE CYCLE • In the conceptual design phase, the company decides how to meet user needs. • Tasks in this phase include: • Identify and evaluate design alternatives • Develop design specifications • Deliver conceptual design requirements • These requirements will be forwarded to the information systems steering committee.
SYSTEMS DEVELOPMENT LIFE CYCLE • The five stages in the systems development life cycle are: • Systems analysis • Conceptual design • Physical design • Implementation and conversion • Operation and maintenance
SYSTEMS DEVELOPMENT LIFE CYCLE • In the physical design phase, the broad, user-oriented requirements of the conceptual design are translated into detailed specifications that can be used by programmers to code the programs. • Tasks include: • Design outputs, database, and inputs • Develop programs • Develop procedures • Design controls • Deliver developed system • Goes to information systems steering committee
SYSTEMS DEVELOPMENT LIFE CYCLE • The five stages in the systems development life cycle are: • Systems analysis • Conceptual design • Physical design • Implementation and conversion • Operation and maintenance
SYSTEMS DEVELOPMENT LIFE CYCLE • This is the capstone phase during which everything comes together. • Tasks include: • Develop an implementation and conversion plan. • Needed because of the complexity and importance of this phase. • Install any new hardware and software. • Train personnel. • New employees may need to be hired and trained or existing employees relocated. • Test the system and make any needed modifications. • Complete the documentation. • Convert from the old to the new system. • Deliver operational system. • Send the final report to the IS steering committee.
SYSTEMS DEVELOPMENT LIFE CYCLE • The five stages in the systems development life cycle are: • Systems analysis • Conceptual design • Physical design • Implementation and conversion • Operation and maintenance
SYSTEMS DEVELOPMENT LIFE CYCLE • Once the system is up and running, operations and monitoring continue. • Tasks include: • Fine-tune and do post-implementation review. • Operate the system. • Periodically, review and modify the system. • Do ongoing maintenance. • Deliver improved system.
SYSTEMS DEVELOPMENT LIFE CYCLE • Eventually, a major modification or system replacement is necessary, and the systems development life cycle (SDLC) will start over. • In addition to the preceding five phases, three activities are performed throughout the life cycle: • Planning. • Managing behavioral reactions to change. • Assessing ongoing feasibility. • These three activities will be discussed in this chapter. • Additionally, the first phase in the SDLC, systems analysis, will be discussed in more detail.
THE PLAYERS • Many people are involved in developing and successfully implementing an AIS, including: • Top management • Accountants • The information systems steering committee • The project development team • Systems analysts • Computer programmers • External players
THE PLAYERS • Many people are involved in developing and successfully implement an AIS, including: • Top management • Accountants • The information systems steering committee • The project development team • Systems analysts • Computer programmers • External players
THE PLAYERS • Top management’s role in systems development is to: • Provide support and encouragement a clear signal that user involvement is important. • Help align the systems with corporate strategies. • Establish system goals and objectives. • Review IS department performance and leadership. • Establish policies for project selection and organizational structure. • Participate in important systems decisions.
THE PLAYERS • User management needs to: • Determine information requirements for departmental projects. • Assist systems analysts with project cost-benefit estimates. • Assign key staff members to development projects. • Allocate funds.
THE PLAYERS • Many people are involved in developing and successfully implement an AIS, including: • Top management • Accountants • The information systems steering committee • The project development team • Systems analysts • Computer programmers • External players
THE PLAYERS • Accountants also play an important role in systems development: • As AIS users, they must determine their information needs and systems requirements and communicate them to system developers. • As members of project development teams or steering committees, they help management in the development process. • They are also active in: • Designing system controls and monitoring and testing these controls. • Ensuring the system is easy to audit. • Controls and “auditability” need to be built in early to minimize costs and inefficiencies later.
THE PLAYERS • Many people are involved in developing and successfully implement an AIS, including: • Top management • Accountants • The information systems steering committee • The project development team • Systems analysts • Computer programmers • External players
THE PLAYERS • The information systems steering committee is an executive-level committee whose duty is to plan and oversee the IS function. • Consists of high level management, such as: • Controller • IS Manager • User department managers • Sets policies to govern the AIS and assure top-management participation, guidance, and control. • Attempts to encourage goal congruence and reduce goal conflict.
THE PLAYERS • Many people are involved in developing and successfully implement an AIS, including: • Top management • Accountants • The information systems steering committee • The project development team • Systems analysts • Computer programmers • External players
THE PLAYERS • The project development team includes systems specialists, managers, accountants, auditors, and users whose responsibility is to guide development. • Their job: • Plan each project. • Monitor to ensure timely and cost-effective completion. • Ensure the human element is considered. • Communicate project status to top management and steering committee. • Communicate and meet with users to: • Consider ideas • Discuss progress • Eliminate surprises • The team approach produces more effective results and better user acceptance.
THE PLAYERS • Many people are involved in developing and successfully implement an AIS, including: • Top management • Accountants • The information systems steering committee • The project development team • Systems analysts • Computer programmers • External players
THE PLAYERS • Systems analysts study existing systems, design new ones, and prepare specifications that are used by programmers. • They interact with technical personnel and users to bridge the gap. • They are responsible for ensuring the system meets user needs.
THE PLAYERS • Many people are involved in developing and successfully implement an AIS, including: • Top management • Accountants • The information systems steering committee • The project development team • Systems analysts • Computer programmers • External players
THE PLAYERS • Computer programmers write the computer programs, using the specs developed by the systems analysts. • They also modify and maintaining existing programs.
THE PLAYERS • Many people are involved in developing and successfully implement an AIS, including: • Top management • Accountants • The information systems steering committee • The project development team • Systems analysts • Computer programmers • External players
THE PLAYERS • External players include: • Customers • Vendors • Auditors • Governmental entities • Their needs must also be met in systems development.
PLANNING SYSTEMS DEVELOPMENT • Several activities must be performed at various times throughout the SDLC. • One of these activities is planning. • The organization should have plans for: • The long range. • Each systems development project. • Each phase of each systems development project. • We’ll discuss these plans and a number of techniques to develop them.
PLANNING SYSTEMS DEVELOPMENT • We’ve all experienced the disasters that occur when we fail to plan. • When you got it home, you realized it wasn’t compatible with your existing printer and scanner. • Furthermore, it wasn’t equipped for broadband Internet access and you had been hoping to switch to broadband. • By the time you spend the money and buy the parts to equip the computer to do what you want it to do, you find that you could have bought a leading-edge computer for less money. • Suppose you bought a personal computer on impulse without thinking about what you wanted to do with it.
PLANNING SYSTEMS DEVELOPMENT • Systems development planning is an important step for the following key reasons: • Consistency with the organization’s strategic plan. • Efficiency achieved through coordination of the subsystems. • Cutting edge technology and techniques. • Lower costs due to lack of duplication, wasted effort, time overruns, and cost overruns. • Adaptability for future changes.
PLANNING SYSTEMS DEVELOPMENT • When a system is poorly planned, a company must often return to a prior phase and correct errors and design flaws. • These returns are costly and result in delays, frustration, and low morale.
PLANNING SYSTEMS DEVELOPMENT • Two types of systems development plans are needed: • Individual project plans developed by the project teams. • A master plan developed by the IS steering committee.
PLANNING SYSTEMS DEVELOPMENT • Two types of systems development plans are needed: • Individual project plans developed by the project teams. • A master plan developed by the IS steering committee.
PLANNING SYSTEMS DEVELOPMENT • Individual project plans contain: • A cost-benefit analysis. • Developmental and operational requirements, including: • Human resources • Hardware • Software • Financial resources • A schedule of activities to develop and operate the new application.
PLANNING SYSTEMS DEVELOPMENT • Two types of systems development plans are needed: • Individual project plans developed by the project teams. • A master plan developed by the IS steering committee.
PLANNING SYSTEMS DEVELOPMENT • A master plan specifies: • What the system will consist of • How it will be developed. • Who will develop it. • How needed resources will be acquired. • Where the AIS is headed. • It also provides: • Status of projects in process. • Prioritization of planned projects and criteria for establishing priorities. • Timetables for development.