Systems Analysis & Design (Sixth Edition) 1 Chapter 1 Introduction to Systems Analysis and Design

2 Chapter Objectives Discuss the impact of information technology on business strategy and success Define an information system and describe its components Use profiles and models to understand business functions and operations Explain how the Internet has affected business strategies and relationships Identify various types of information systems and explain who uses them

3 Chapter Objectives Explain systems development tools, including modeling, prototyping, and CASE tools Distinguish between structured analysis and object-oriented methodology Describe the systems development life cycle Discuss the role of the information technology department and the systems analysts who work there

4 Introduction Companies use information as a weapon in the battle to increase productivity, deliver quality products and services, maintain customer loyalty, and make sound decisions Information technology can mean the difference between success and failure

5 The Impact of Information Technology Information Technology Combination of hardware and software products and services that companies use to manage, access, communicate, and share information A vital asset that must be used effectively, updated constantly, and safeguarded carefully

6 The Impact of Information Technology The Future of IT Accounted for almost 30 percent of economic growth in 2003 Online population worldwide increased 106 percent between

7 The Impact of Information Technology The Role of Systems Analysis and Design Systems Analysis and Design Step-by-step process for developing high-quality information systems Information System Combines information technology, people, and data to support business requirements Systems Analyst Plan, develop, and maintain information systems

8 The Impact of Information Technology Who Develops Information Systems? In-house applications Software packages (outside vendors) Internet-based application services Outsourcing (outside development) Custom solutions (IT consultants) Enterprise-wide software strategies How versus What

9 Information System Components System A set of related components that produces specific results Mission-critical system A system that is vital to a company’s operations

10 Hardware Moore’s Law Software System software Network operating system Application software Enterprise applications Information System Components

11 Information System Components Data The raw material that an information system transforms into useful information Tables Linking

12 Information System Components Processes Define the tasks and business functions that users, managers, and IT staff members perform to achieve specific results People Users, or end users, are the people who interact with an information system, both inside and outside the company

13 Understanding The Business Business Profile Business Models Business models Business process BPR (business process reengineering)

14 Understanding The Business New Kinds of Companies Companies are classified based on main activities: Product-oriented Service-oriented Brick-and-mortar Dot-com (.com) or Internet- dependent

15 Impact of the Internet E-Commerce (I-Commerce) B2C (Business-to-Consumer) B2B (Business-to-Business) EDI, XML, HTML Web-Based Development WebSphere,.NET Web services

16 How Business Uses Information Systems In the past, IT managers divided systems into categories based on the user group that the system served: Office systems Operational systems Decision support systems Executive information systems

17 How Business Uses Information Systems Today, it makes more sense to identify a system by its functions, rather than by users Enterprise computing systems Transaction processing systems Business support systems Knowledge management systems User productivity systems

18 How Business Uses Information Systems Enterprise computing systems Support company-wide operations and data management requirements Enterprise resource planning (ERP)

19 How Business Uses Information Systems Transaction processing systems Efficient because they process a set of transaction-related commands as a group rather than individually

20 How Business Uses Information Systems Business support systems Provide job-related information to users at all levels of a company Management information systems (MIS) Radio frequency identification (RFID) What-if analysis

21 How Business Uses Information Systems Knowledge management systems Called expert systems Simulate human reasoning by combining a knowledge base and inference rules Many use fuzzy logic

22 How Business Uses Information Systems User productivity systems Technology that improves productivity Groupware Information systems integration Most large companies require systems that combine transaction processing, business support, knowledge management, and user productivity features

23 Information System Users and Their Needs organizational model A systems analyst must understand the company’s organizational model in order to recognize who is responsible for specific processes and decisions and to be aware of what information is required by whom A typical organizational model, shown here, identifies the business functions and organizational levels Organizational Model

24 Information System Users and Their Needs Top managers Middle Managers and Knowledge Workers Supervisors and Team Leaders Operational Employees

25 Systems Development Tools and Techniques Systems analysts must know how to use a variety of techniques: Modeling Prototyping CASE (computer-aided systems engineering) tools in order to plan, design and implement the systems Systems analysts work with these tools/techniques in a team environment

26 Systems Development Tools and Techniques Modeling is used to describe and simplify an information system: Business model AKA Requirements model Data model Object model Network model Process model

27 Systems Development Tools and Techniques Prototyping Utilizes a Prototype Can speed up development significantly Disadvantage: Important decisions might be made too early, before business or IT issues are thoroughly understood Advantage: Can be an extremely valuable tool, based on careful fact-finding/modeling

28 Systems Development Tools and Techniques Computer-Aided Systems Engineering (CASE) Tools Framework for systems development and support a wide variety of design methodologies CASE tools (websites that list CASE tools)

29 Systems Development Methods Structured analysis* and Object-oriented analysis are both popular methodologies for developing information systems In addition to the above methodologies, a systems analyst should understand alternatives JAD RAD Microsoft Solutions Framework (MSF) Homegrown / Consultant / Software Company * Used most often

30 Systems Development Methods Structured Analysis Systems development life cycle (SDLC) Uses a set of process models to describe a system graphically (Website with information on structured analysis and OO analysis)

31 Systems Development Methods Object-oriented (O-O) analysis O-O analysis combines data & processes into objects Object is a member of a class Class is a collection of similar objects Objects possess characteristics called properties Methods change an object’s properties Messages request specific behavior or information from another object

32 Systems Development Methods Joint Application Development and Rapid Application Development JAD – Team based fact finding RAD – compressed version of the entire process Other development methodologies Microsoft Solutions Framework (MSF)

33 The Systems Development Life Cycle SDLC used to plan and manage the systems development process It includes the following steps: Systems planning phase Systems analysis phase Systems design phase Systems implementation phase Systems operation, support, and security phase Deliverable or end product

34 The Systems Development Life Cycle Traditionally pictured as a waterfall model, but is also presented as an interactive model depicting real world practice and the constant dialog among users, managers, and systems developers Interactive Model Waterfall Model

35 The Systems Development Life Cycle Systems planning Systems request – begins the process & describes problems or desired changes Purpose is to identify the nature and scope of the business opportunity or problem Systems planning includes preliminary investigation whose key part is a feasibility study

36 The Systems Development Life Cycle Systems Analysis Purpose is to build a logical model of the new system First step is requirements modeling, where you investigate business processes and document what the new system must do End product is the system requirements document

37 The Systems Development Life Cycle Systems Design Purpose is to create a blueprint that will satisfy all documented requirements Identify all outputs, inputs, and processes Avoid misunderstanding through manager and user involvement End product is systems design specification

38 The Systems Development Life Cycle Systems Implementation New system is constructed Write, test, & document programs (CODING) File conversion occurs (Whether a purchased package or not  configure s/w, etc.) Users, managers, IT staff trained to operate and support the system Systems evaluation performed

39 The Systems Development Life Cycle Systems operation, support, and security New system supports operations Maintenance changes correct errors or meet requirements Enhancements increase system capability Well-designed system will be secure, reliable, maintainable, and scalable SDLC ends with system replacement

40 Systems Development Guidelines Planning Involve users throughout the development process Listening is very important Create a time table with major milestones Identify interim checkpoints Remain flexible Develop accurate cost and benefit information

41 Information Technology Department The information technology (IT) department develops and maintains a company’s information systems The IT group provides technical support which includes 6 main functions listed below:

42 Information Technology Department Application Development Team may include users, managers and IT staff members Systems Support and Security Provides hardware and software support User Support Provides users with technical information, training, and productivity support Help desk

43 Information Technology Department Database Administration Database design, management, security, backup, and user access Network Administration Includes hardware and software maintenance, support, and security Web Support Design and construction of Web pages Important for e-commerce Webmaster

44 The Systems Analyst Position A systems analyst investigates, analyzes, designs, develops, installs, evaluates, and maintains a company’s information systems On large projects, the analyst works as a member of an IT department team Smaller companies often use consultants to perform the work

45 The Systems Analyst Position Responsibilities Translate business requirements into practical IT projects to meet needs Required Skills and Background Solid communication skills Good analytical ability Technical knowledge is helpful Understanding of business and processes

46 The Systems Analyst Position Certification Professional credential Career Opportunities Job titles Company organization Company size Corporate culture Salary, location, and future growth

47 Chapter Summary IT is a combination of hardware and software that support business The essential components of an information system are hardware, software, data, processes, and people Companies are product-oriented, service- oriented, or a combination of the two

48 Chapter Summary Organization structure usually includes levels. Each level has different responsibilities and information needs Systems analysts use modeling, prototyping, and CASE tools. Modeling produces a graphical representation of the process, prototyping involves creation of an early working model, and CASE tools assist in various systems development tasks

49 Chapter Summary The Systems Development Life Cycle (SDLC) consists of five phases: systems planning, systems analysis, systems design, systems implementation, and systems operation, support, and security Systems analysts need a combination of technical and business knowledge, analytical ability, and communication skills Any questions?