SYSTEMS ANALYSIS AND DESIGN METHODS 6 th Edition

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SYSTEMS ANALYSIS AND DESIGN METHODS 6 th Edition Whitten Bentley Dittman C H A P T E R 1 Irwin/Mc. Graw-Hill THE CONTEXT OF SYSTEMS ANALYSIS AND DESIGN METHODS Copyright © 2004 The Mc. Graw-Hill Companies. All Rights reserved

SYSTEMS ANALYSIS AND DESIGN METHODS 6 th Edition Whitten Bentley Dittman About class… • Try not to have long…long lectures – Very late class – Tired • Typical class format – Lecture – Discussion Irwin/Mc. Graw-Hill Copyright © 2004 The Mc. Graw-Hill Companies. All Rights reserved

SYSTEMS ANALYSIS AND DESIGN METHODS 6 th Edition Whitten Bentley Dittman Importance of Systems Analysis and Design • Examples – Denver airport Baggage-handling information system – World. Com (now MCI) billing systems – California DMV system • All my teaching slides (e. g. , lecture note) are somewhat detail…. Save your time (taking note)…. easy to follow…. eliminate any guess (e. g. , accent, pronunciation)…. Irwin/Mc. Graw-Hill Copyright © 2004 The Mc. Graw-Hill Companies. All Rights reserved

SYSTEMS ANALYSIS AND DESIGN METHODS 6 th Edition Whitten Bentley Dittman New Denver airport • • Twice the size of Manhattan, NY 10 times wider than London airport Big enough to land three jets simultaneously-in bad weather Baggage-handling information system – – One of kind… Expensive: $1. 7 billion (original price) Very large size…. The most advanced and sophisticated automated baggage handling system Irwin/Mc. Graw-Hill Copyright © 2004 The Mc. Graw-Hill Companies. All Rights reserved

SYSTEMS ANALYSIS AND DESIGN METHODS 6 th Edition Whitten Bentley Dittman Scale of baggage-handling system • 21 miles of steel track – Tearing like intelligent coal-mine cars • 4, 000 independent "telecars" route and deliver luggage between the counters, gates and claim areas of 20 different airlines. • Size of the system – 100 computers are networked to one another and to 5, 000 electric eyes – 400 radio receivers – 56 bar-code scanners orchestrates the safe and timely arrival of every valise and ski bag. Irwin/Mc. Graw-Hill Copyright © 2004 The Mc. Graw-Hill Companies. All Rights reserved

SYSTEMS ANALYSIS AND DESIGN METHODS 6 th Edition Whitten Bentley Dittman Result • Scheduled to open Nov, 94 • Delayed nine-month because of system glitches. – Original price $1. 7 billion, final cost $4. 5 billion – Their bond rating demoted to junk and their budget hemorrhaging red ink at the rate of $1. 1 million a day in interest and operating costs. • $ 1. 1 M can worth more today!! Irwin/Mc. Graw-Hill Copyright © 2004 The Mc. Graw-Hill Companies. All Rights reserved

SYSTEMS ANALYSIS AND DESIGN METHODS 6 th Edition Whitten Bentley Dittman World. Com (now under MCI) • Fierce competitors to AT&T and Sprint • Used to have: – 88, 000 employees – 60, 000 miles of telephone lines around the world – Revenue of $40 billion • Collapsed because of the accounting fraud – $11 billion – The biggest ever • A main trigger – Simple: failure of systems integration – Four different billing systems Irwin/Mc. Graw-Hill Copyright © 2004 The Mc. Graw-Hill Companies. All Rights reserved

SYSTEMS ANALYSIS AND DESIGN METHODS 6 th Edition Whitten Bentley Dittman California DMV system • Straightforward task – Provide one-stop service: merge of the state’s driver license and vehicle registration systems • Started 1991 and stopped 1998 – In Dec 98, the agency pulled the plug and walked away… – wasting $44. 3 million investment. . • Y 2 K problem (very simple problem…) – Analysts and designers couldn’t think that systems can live longer than them…. – Billions of dollars were wasted ($740 billion) Irwin/Mc. Graw-Hill Copyright © 2004 The Mc. Graw-Hill Companies. All Rights reserved

SYSTEMS ANALYSIS AND DESIGN METHODS 6 th Edition Whitten Bentley Dittman Chapter 1 – The Context of Systems Analysis & Design Methods • information system and name seven types of information system applications. • Identify different types of stakeholders who use or develop information systems, and give examples of each. • Define the unique role of systems analysts in the development of information systems. • Identify those skills needed to successfully function as an information system analyst. • Describe current business drivers that influence information systems development. • Describe current technology drivers that influence information systems development. • Briefly describe a simple process for developing information systems. • Differentiate between the waterfall and the iterative/incremental approaches to systems development. Irwin/Mc. Graw-Hill Copyright © 2004 The Mc. Graw-Hill Companies. All Rights reserved

SYSTEMS ANALYSIS AND DESIGN METHODS 6 th Edition Whitten Bentley Dittman Why information systems? • Information age – Change of Paradigm – Bill Gates wealth • Globalization – Dramatic increase of global management • Organizational Change – Downsizing (less hierarchical) – Less traditional middle management – Knowledge asset management • Speed – Impossible without IT Irwin/Mc. Graw-Hill Copyright © 2004 The Mc. Graw-Hill Companies. All Rights reserved

SYSTEMS ANALYSIS AND DESIGN METHODS 6 th Edition Whitten Bentley Dittman IS vs. IT An information system (IS) is an arrangement of people, data, processes, and information technology that interact to collect, process, store, and provide as output the information needed to support an organization. Information technology is a contemporary term that describes the combination of computer technology (hardware and software) with telecommunications technology (data, image, and voice networks). Irwin/Mc. Graw-Hill Copyright © 2004 The Mc. Graw-Hill Companies. All Rights reserved

SYSTEMS ANALYSIS AND DESIGN METHODS 6 th Edition Whitten Bentley Dittman Stakeholders: Players in the Systems Game • A stakeholder is any person who has an interest in an existing or proposed information system. Stakeholders can be technical or nontechnical workers. They may also include both internal and external workers. • Figure 1 -1: next slide – – – System owners System users System designers System builders Systems analysts (project managers) Irwin/Mc. Graw-Hill Copyright © 2004 The Mc. Graw-Hill Companies. All Rights reserved

SYSTEMS ANALYSIS AND DESIGN METHODS 6 th Edition Whitten Bentley Dittman Stakeholders’ Perspectives on an Information System Irwin/Mc. Graw-Hill Copyright © 2004 The Mc. Graw-Hill Companies. All Rights reserved

SYSTEMS ANALYSIS AND DESIGN METHODS 6 th Edition Whitten Bentley Dittman System Owners System owners – an information system’s sponsor and executive advocate, usually responsible for funding the project of developing, operating, and maintaining the information system. – They usually come from the ranks of management. - medium (large) IS: middle (executive) managers - smaller IS: middle or supervisory Primary Concerns - how much will the systems cost? - how much value or what benefits will the system return to the business? CSUB enrollment (registration) system owners? Irwin/Mc. Graw-Hill Copyright © 2004 The Mc. Graw-Hill Companies. All Rights reserved

SYSTEMS ANALYSIS AND DESIGN METHODS 6 th Edition Whitten Bentley Dittman System Users System users – a “customer” who will use or is affected by an IS on a regular basis • capturing, validating, entering, responding to, storing, and exchanging data and information – Make up the vast majority of the information workers in any IS – Primary concern: get the job done using an IS! – Internal users • Clerical and service workers, technical and professional staff, supervisors, middle managers, and executive managers – External users • Internet EC consumers, suppliers, partners… CSUB enrollment (registration) system users? - Internal users? - External users? Irwin/Mc. Graw-Hill Copyright © 2004 The Mc. Graw-Hill Companies. All Rights reserved

SYSTEMS ANALYSIS AND DESIGN METHODS 6 th Edition Whitten Bentley Dittman System Designers and System Builders System designer – a technical specialist who translates system users’ business requirements and constraints into technical solution. – DBA, Network architects, web designer, security experts… System builders – a technical specialist who constructs information systems and components based on the design specifications generated by the system designers. – Programmers (applications, systems, and DB), network administrators, web masters. . CSUB enrollment (registration) system designer and builders? Irwin/Mc. Graw-Hill Copyright © 2004 The Mc. Graw-Hill Companies. All Rights reserved

SYSTEMS ANALYSIS AND DESIGN METHODS 6 th Edition Whitten Bentley Dittman Systems Analysts Systems analyst – a specialist who studies the problems and needs of an organization to determine how people, data, processes, and information technology can best accomplish improvements for the business. Roles: − Bridge (facilitator) between management and technical specialist: next slide − Understand both business and computing − Initiate change within an organization − Ultimately, a problem solver Irwin/Mc. Graw-Hill Copyright © 2004 The Mc. Graw-Hill Companies. All Rights reserved

SYSTEMS ANALYSIS AND DESIGN METHODS 6 th Edition Whitten Bentley Dittman Where Do Systems Analysts Work? • May be permanently assigned to a team that supports a specific business function • May also be pooled and temporarily assigned to specific projects – Figure on next slide • Career prospect for SA – Textbook page 19 Irwin/Mc. Graw-Hill Copyright © 2004 The Mc. Graw-Hill Companies. All Rights reserved

SYSTEMS ANALYSIS AND DESIGN METHODS 6 th Edition Whitten Bentley Dittman Skills Needed by the Systems Analyst • Working knowledge of (existing and emerging) IT • Computer programming experience and expertise • General business problem-solving skills • Good interpersonal communication skills – Business writing class (Dr. John Stark) – Technical business skill class (Dr. Ron Pimentel) • Good interpersonal relation skills • Flexibility and adaptability • Character and ethics Irwin/Mc. Graw-Hill Copyright © 2004 The Mc. Graw-Hill Companies. All Rights reserved

SYSTEMS ANALYSIS AND DESIGN METHODS 6 th Edition Whitten Bentley Dittman Other Stakeholders External Service Provider (ESP) – a systems analyst, system designer, or system builder who sells his or her expertise and experience to other businesses to help those businesses purchase, develop, or integrate their information systems solutions; may be affiliated with a consulting or services organization. • Accenture (previously Anderson Consulting – spun off from Arthur Anderson consulting) • Consultants, Contracted SA, SD, SB, programmers. . Project Manager – an experienced professional who accepts responsibility for planning, monitoring, and controlling projects with respect to schedule, budget, deliverables, customer satisfaction, technical standards, and system quality. • Usually senior analysts Irwin/Mc. Graw-Hill Copyright © 2004 The Mc. Graw-Hill Companies. All Rights reserved

SYSTEMS ANALYSIS AND DESIGN METHODS 6 th Edition Whitten Bentley Dittman Two Drivers for Today’s Information Systems • Business Drivers – Globalization of the Economy – Electronic Commerce – Security and Privacy – Collaboration and Partnership – Knowledge Asset Management – Continuous Improvement and Total Quality Management – Business Process Redesign Irwin/Mc. Graw-Hill Copyright © 2004 The Mc. Graw-Hill Companies. All Rights reserved

SYSTEMS ANALYSIS AND DESIGN METHODS 6 th Edition Whitten Bentley Dittman Two Drivers for Today’s Information Systems • Technology Drivers – Networks and the Internet – Mobile and Wireless Technologies – Object Technologies – Collaborative Technologies – Enterprise Applications Irwin/Mc. Graw-Hill Copyright © 2004 The Mc. Graw-Hill Companies. All Rights reserved

SYSTEMS ANALYSIS AND DESIGN METHODS 6 th Edition Whitten Bentley Dittman Object Technologies Object technology – a software technology that defines a system in terms of objects that consolidate data and behavior (into objects). – Objects are reusable and extensible – Object-oriented programming languages include C++, java, Smalltalk, and Visual Basic. net Object-oriented analysis and design – a collection of tools and techniques for systems development that will utilize object technologies to construct a system and its software. – Works well in programming level – May not need some of analysis and design level (e. g. , database – structured tools and techniques) – Hybrid analysis and design Irwin/Mc. Graw-Hill Copyright © 2004 The Mc. Graw-Hill Companies. All Rights reserved

SYSTEMS ANALYSIS AND DESIGN METHODS 6 th Edition Whitten Bentley Dittman A Simple System Development Process System development process – a set of activities, methods, best practices, deliverables, and automated tools that stakeholders use to develop and maintain information systems and software. Justice Department SDLC document A general problem-solving approach 1. 2. 3. 4. 5. 6. 7. Identify the problem. Analyze and understand the problem. Identify solution requirements or expectations. Identify alternative solutions and choose the “best” course of action. Design the chosen solution. Implement the chosen solution. Evaluate the results. If the problem is not solved, return to step 1 or 2 as appropriate. Irwin/Mc. Graw-Hill Copyright © 2004 The Mc. Graw-Hill Companies. All Rights reserved

SYSTEMS ANALYSIS AND DESIGN METHODS 6 th Edition Whitten Bentley Dittman Sequential versus Iterative Development Not good strategy for most modern systems development Iterative (incremental) approach is more popular strategy Irwin/Mc. Graw-Hill Copyright © 2004 The Mc. Graw-Hill Companies. All Rights reserved