1. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall Essentials of Systems Analysis and Design Fourth Edition Joseph S. Valacich Joey F. George Jeffrey A. Hoffer Chapter 1 The Systems Development Environment 1.1

2. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall Learning Objectives Define information systems analysis and design Discuss the modern approach to systems analysis and design that combines both process and data views of systems Describe the role of the systems analyst in information systems development 1.2

3. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall Learning Objectives (continued) Describe three types of information systems: Transaction Processing Systems (TPS) Management Information Systems (MIS) Decision Support Systems (DSS) Describe the information systems development life cycle (SDLC) 1.3

4. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall Learning Objectives (continued) List alternatives to the systems development life cycle, including a description of the role of computer aided software engineering (CASE) tools in systems development 1.4

5. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall Chapter Preview Systems Analysis is a proven method to help business utilize information to its fullest capacity Systems Development Life Cycle (SDLC) Central to Information Systems Development 1.5

6. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall Chapter Preview Four key SDLC steps: Planning and selection Analysis Design Implementation Note that these steps may vary in each organization depending on its goals. 1.5

7. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall What is Information Systems Analysis and Design? A method used by companies to create and maintain systems that perform basic business functions Main goal is to improve employee efficiency by applying software solutions to key business tasks A structured approach must be used in order to ensure success 1.6

8. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall What is Information Systems Analysis and Design? (continued) Systems Analysts perform analysis and design based upon: Understanding of organization’s objectives, structure and processes Knowledge of how to exploit information technology for advantage Fig 1-1 illustrates the Systems Development Life Cycle, a four-phased approach used throughout this text 1.7

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10. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall Systems Analysis and Design: Core Concepts Major goal: to improve organizational systems by developing or acquiring application software and training employees in its use Application software, or a system, supports organizational functions or processes Inventory management system Payroll system 1.10

11. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall Systems Analysis and Design: Core Concepts (continued) System: Turns data into information and includes: Hardware and system software Documentation and training materials Job roles associated with the system Controls to prevent theft or fraud The people who use the software to perform their jobs Figure 1.2 illustrates all the components of a system 1.11

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13. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall Software Engineering Process A process used to create an information system Consists of: Methodologies  A sequence of step-by-step approaches that help develop the information system Techniques  Processes that the analyst follows to ensure thorough, complete, and comprehensive analysis and design Conducting thorough interviews with current and future users Planning and managing the activities in a systems development project Diagramming how the system will function 1.13

14. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall Software Engineering Process Consists of: Tools  Computer programs that aid in applying techniques These three elements work together to form an organizational approach to systems analysis and design 1.14

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16. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall System A system is an interrelated set of business procedures used within one business unit working together for a purpose A system has nine characteristics A system exists within an environment A boundary separates a system from its environment 1.16

17. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall Characteristics of a System Components (Subsystem) Interrelated Components Boundary Purpose Environment (everything outside the system’s boundary that influences the system) Interfaces Constraints (limits) Input (from its environment) Output (to its environment) 1.17

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19. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall Important System Concepts Decomposition The process of breaking down a system into smaller components Allows the systems analyst to:  Break a system into small, manageable and understandable subsystems  Focus on one area at a time, without interference from other areas  Concentrate on component pertinent to one group of users without confusing users with unnecessary details  Build different components at independent times and have the help of different analysts 1.19

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21. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall Important System Concepts (continued) Modularity Process of dividing a system into modules of a relatively uniform size Modules simplify system design Coupling Subsystems that are dependent upon each other are coupled Cohesion Extent to which a subsystem performs a single function 1.21

22. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall A Modern Approach to Systems Analysis and Design Today, systems development focuses on Systems Integration Allows hardware and software from different vendors to work together Enables procedural language systems to work with visual programming systems Visual programming environment uses client/server model 1.22

23. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall Your Role in Systems Development Study problems and needs of an organization Determine best approach to improving organization through use of: People Methods Information technology Help system users and managers define their requirements for new or enhanced information systems 1.23

24. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall Your Skills As System Analyst (1) Analytical skills: to understand the organization and its functions, to identify opportunities and problems, and to analyze and solve problems. Systems thinking: ability to see organizations and information systems as systems. Provides a framework from which to see the important relationships among information systems, the organizations they exist in, and the environment in which the organizations themselves exist. 1.24

25. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall Your Skills As System Analyst (2) Technical skills: help you understand the potential and the limitations of information technology. Able to work with programming language, various operating systems and computer hardware platforms 1.25

26. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall Your Skills As System Analyst (3) Management skills: help you manage projects, resources, risk, and change (4) Interpersonal skills: help you work with end users as well as with other analysts and programmers Effective written and oral communication  Leading meetings  Interviewing end users and listening 1.26

27. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall Types of Information Systems and Systems Development Transaction Processing Systems (TPS) Automate handling of data about business activities (transactions). Example: Bank’s TPS Data about each transaction are captured, transactions are verified and accepted or rejected, and validated transactions are stored 1.27

28. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall Types of Information Systems and Systems Development Transaction Processing Systems (TPS) You need to focus on the firm’s current procedures for processing transactions. How does the organization track, capture, process, and output data?  The goal is to improve transaction processing by speeding it up, using fewer people, improving efficiency and accuracy, integrating it with other organizational information systems, or providing information not previously available 1.28

29. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall Types of Information Systems and Systems Development Management Information Systems (MIS) Convert raw data from transaction processing system into meaningful form (standard reports) You need a good understanding of what kind of information managers require and how managers use information in their jobs MIS often require data from several transaction processing systems 1.29

30. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall Types of Information Systems and Systems Development Decision Support Systems (DSS) Designed to help decision makers Provide interactive environment for decision making The systems analysis and design for a DSS often concentrates on the three main DSS components: database, model base(mathematical or graphical model) and user dialogue 1.30

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32. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall Developing Information Systems and the Systems Development Life Cycle Systems Development Methodology A standard process followed in an organization to conduct all the steps necessary to  analyze  design  implement  and maintain information systems. 1.32

33. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall Developing Information Systems and the Systems Development Life Cycle (continued) Systems Development Life Cycle A common methodology for systems development in many organizations Series of steps used to manage the phases of development for an information system Consists of four phases:  Planning and Selection  Analysis  Design  Implementation and Operation 1.33

34. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall Developing Information Systems and the Systems Development Life Cycle (continued) Phases are not necessarily sequential Each phase has a specific outcome and deliverable Every company customizes the life-cycle model to its individual needs  Even if a particular methodology does not look like a cycle, many of the SDLC steps are performed, and SDLC techniques and tools are used  The book follows a generic SDLC model 1.34

35. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall Phases of the Systems Development Life Cycle 1. Systems Planning and Selection Two Main Activities  (a) Identification of need: someone identify the need for a new or enhanced system. Information needs are examined, and projects to meet these needs are identified. The needs may result from Problems in current procedures Desire to perform additional tasks Using information technology to capitalize on an existing opportunity  A feasibility study should be conducted to determine the economic and organizational impact of the system 1.35

36. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall Phases of the Systems Development Life Cycle 1. Systems Planning and Selection Two Main Activities  (b) Investigation and determination of scope: The team of systems analysts then produces a specific plan for the proposed project for the team to follow. This plan specifies the time and resources needed for its execution 1.36

37. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall Phases of the Systems Development Life Cycle 2. Systems Analysis Study of current procedures and information systems  Determine requirements  Generate alternative designs match the requirements  Compare alternatives to see which best meets the requirements within the cost, labor, and technical levels the organization is willing to commit to the development process  Recommend best alternative 1.37

38. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall Phases of the Systems Development Life Cycle (continued) 3. System Design: convert the description of the recommended alternative solution into logical and then physical system specification Logical Design  Concentrates on business aspects of the system, that is, how the system will impact the functional units within the organization Physical Design  Technical specifications: programming languages, database systems and file structures, hardware platform, operating system and network enviornment 1.38

39. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall Phases of the Systems Development Life Cycle (continued) 4. System Implementation and Operation: Turn system specifications into a working system that is tested and then put into use Implementation  Coding  Testing  Installation: the new system becomes a part of the daily activities of the organization  User Training  Documentation 1.39

40. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall Phases of the Systems Development Life Cycle (continued) System Implementation and Operation (continued)  During operation, programmers make the changes that users ask for and modify the system to reflect changing business conditions  System obsolescence 1.40

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42. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall Approaches to Development Prototyping Building a scaled-down working version of the system. A prototype can be developed with a CASE tools which automate steps in system development life cycle Advantages:  Users are involved in design  Captures requirements in concrete form 1.42

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44. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall Approaches to Development (continued) Computer-Assisted Software Engineering (CASE) Tools Automated software tools used by systems analysts to develop information systems Can be used throughout SDLC Product and tool integration is provided through a repository (A centralized DB that contains all diagrams, forms and reports definitions,……) 1.44

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46. Approaches to Development (continued) General types of CASE tools  Diagramming tools  Computer display and report generators: how system “look and feel” to users  Analysis tools: for checking  Repository  Documentation generators  Code generators 1.46

47. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall Approaches to Development (continued) Joint Application Design (JAD) Users, Managers and Analysts work together for several days System requirements are reviewed Structured meetings Rapid Application Development (RAD) Utilizes prototyping to delay producing detailed system design documents until after user requirements are clear 1.47

48. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall Approaches to Development (continued) Participatory Design (PD) Emphasizes role of the user ( Each user has an equal voice in determining system requirements ) Entire user community can be involved in design Agile Methodologies Focuses on  Adaptive methodologies  People instead of roles  Self-adaptive development process 1.48

49. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall Summary Information systems analysis and design Process of developing and maintaining an information system Modern approach to systems analysis Process-oriented Data-oriented 1.49

50. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall Summary (continued) Role of Systems Analyst Three types of information systems Transaction Processing (TPS) Management Information System (MIS) Decision Support (DSS) 1.50

51. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall Summary (continued) Systems Development Life Cycle (SDLC) Systems Planning and Selection Systems Analysis Systems Design Systems Implementation Alternatives to Systems Development Life Cycle Prototyping Rapid Application Development (RAD) CASE 1.51

52. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall Summary Joint Application Design (JAD) Participatory Design (PD) Agile Methodologies 1.52