Systems Analysis and Design Chapter 1 Introduction PDF

Chapter 1 Introduction to Systems Analysis and Design Copyright ©2017 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part.  Describe the impact of information technology  Define systems analysis...

Chapter 1 Introduction to Systems Analysis and Design Copyright ©2017 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part.  Describe the impact of information technology  Define systems analysis and design and the role of a systems analyst  Define an information system and describe its components  Explain how to use business profiles and models  Explain Internet business strategies and relationships, including B2C and B2B Copyright ©2017 Cengage Learning. All Rights Reserved. May not be scanned, copied 2 or duplicated, or posted to a publicly accessible website, in whole or in part.  Identify various types of information systems and explain who uses them  Distinguish among structured analysis, object-oriented analysis, and agile methods  Explain the waterfall model, and how it has evolved  Discuss the role of the information technology department and the systems analysts who work there Copyright ©2017 Cengage Learning. All Rights Reserved. May not be scanned, copied 3 or duplicated, or posted to a publicly accessible website, in whole or in part.  Information helps companies: Increase productivity Deliver quality products and services Maintain customer loyalty Make sound decisions Use of information technology is vital for organizational success FIGURE 1-1 These headlines show the enormous impact of information technology on our lives. Copyright ©2017 Cengage Learning. All Rights Reserved. May not be scanned, copied 4 or duplicated, or posted to a publicly accessible website, in whole or in part.  Information Technology (IT) ◦ Combination of hardware and software products and services used to manage, access, communicate, and share information  Changing Nature of Information Technology ◦ Change is dramatic and continuous ◦ Advances influence change in business organizations FIGURE 1-2 An employee clocking in with a punch card in 1953. ClassicStock.com/Superstock Copyright ©2017 Cengage Learning. All Rights Reserved. May not be scanned, copied 5 or duplicated, or posted to a publicly accessible website, in whole or in part.  Systems Analysis and Design ◦ Step-by-step process for developing high-quality information systems  Information systems: Combination of technology, people, and data to perform certain business functions  What Does a Systems Analyst Do? ◦ Plans, develops, and maintains information systems ◦ Manages IT projects, including tasks, resources, schedules, and costs ◦ Conducts meetings, delivers presentations, and writes memos, reports, and documentation Copyright ©2017 Cengage Learning. All Rights Reserved. May not be scanned, copied 6 or duplicated, or posted to a publicly accessible website, in whole or in part.  System: Set of related components that produces specific results ◦ Mission-critical systems are vital to a company’s operations  All systems require input data ◦ Data: Basic facts that serve as raw material Information: Data transformed into output FIGURE 1-5 An information system needs these components. Copyright ©2017 Cengage Learning. All Rights Reserved. May not be scanned, copied 7 or duplicated, or posted to a publicly accessible website, in whole or in part.  Hardware ◦ Physical layer of the information system ◦ Moore’s Law was integral to the development of hardware  Software ◦ Controls hardware ◦ System software ◦ Application software  Horizontal system  Vertical system  Legacy system FIGURE 1-6 Server farms provide the enormous power and speed that modern IT systems need. dotshock/Shutterstock.com Copyright ©2017 Cengage Learning. All Rights Reserved. May not be scanned, copied 8 or duplicated, or posted to a publicly accessible website, in whole or in part.  Data ◦ Stored in tables  Processes ◦ Describe the tasks and business functions performed to achieve specific results  People ◦ Stakeholders: Individuals interested in an information system FIGURE 1-7 In a typical payroll system, data is stored in separate tables that are linked to form an overall database. Copyright ©2017 Cengage Learning. All Rights Reserved. May not be scanned, copied 9 or duplicated, or posted to a publicly accessible website, in whole or in part.  Influenced by: ◦ Rapidly increasing globalization ◦ Technology integration for seamless information access ◦ Rapid growth of cloud-based computing and services  All trends are Internet-centric Copyright ©2017 Cengage Learning. All Rights Reserved. May not be scanned, copied 10 or duplicated, or posted to a publicly accessible website, in whole or in part.  The Internet Model ◦ Ecommerce (electronic commerce) ◦ User interface - Enables communication between a data-base management software and a web-based server  Mobile devices interact with the system using apps ◦ Sectors  B2C (business-to-customer)  B2B (business-to-business) Copyright ©2017 Cengage Learning. All Rights Reserved. May not be scanned, copied 11 or duplicated, or posted to a publicly accessible website, in whole or in part.  B2C (Business-to-Customer) ◦ In a single convenient session, customers can:  Do research and compare prices and features  Check availability and arrange delivery  Choose payment methods  B2B (Business-to-Business) ◦ Ecommerce was initially carried out using electronic data interchange (EDI) ◦ Most firms use supply chain management (SCM) software, which helps businesses manage inventory levels, costs, alternate suppliers Copyright ©2017 Cengage Learning. All Rights Reserved. May not be scanned, copied 12 or duplicated, or posted to a publicly accessible website, in whole or in part.  Business Profile ◦ Overview of a company’s mission, functions, organization, products, services, customers, suppliers, competitors, constraints, and future direction  Business Process ◦ Specific set of transactions, events, and results that can be described and documented ◦ Business process model (BPM) ◦ Business process modeling notation (BPMN) Copyright ©2017 Cengage Learning. All Rights Reserved. May not be scanned, copied 13 or duplicated, or posted to a publicly accessible website, in whole or in part. FIGURE 1-8 A simple business model might consist of an event, three processes, and a result. FIGURE 1-9 This sample uses business process modeling notation (BPMN) to represent the same events, processes, and workflow shown in Figure 1-8. Source: Drawio.com Copyright ©2017 Cengage Learning. All Rights Reserved. May not be scanned, copied 14 or duplicated, or posted to a publicly accessible website, in whole or in part.  Current Method ◦ All employees use office productivity systems ◦ Operations users require decision support systems ◦ Systems are defined by their functions and features  Enterprise Computing ◦ Supports company-wide operations and data management requirements  Enterprise resource planning (ERP) systems provide cost-effective support for users and managers throughout the company Copyright ©2017 Cengage Learning. All Rights Reserved. May not be scanned, copied 15 or duplicated, or posted to a publicly accessible website, in whole or in part.  Transaction Processing (TP) Systems ◦ Processes data generated by day-to-day business operations ◦ Examples - Customer order processing, accounts receivable, and warranty claim processing  Business Support Systems ◦ Provide job-related information support to users at all levels of a company  Can work hand-in-hand with a TP system FIGURE 1-11 A single sales transaction consists of six separate tasks, which the TP system processes as a group. Copyright ©2017 Cengage Learning. All Rights Reserved. May not be scanned, copied 16 or duplicated, or posted to a publicly accessible website, in whole or in part.  ◦ Management Information Systems (MIS) ◦ Radio frequency identification (RFID)  Uses high-frequency radio waves to track physical objects  Knowledge Management ◦ Uses a knowledge base and inference rules  Knowledge base: Large database that allows users to find information by entering keywords  Inference rules: Identify data FIGURE 1-12 With an RFID tag, patterns and relationships items can be tracked and monitored throughout the shipping process. © nullplus/photos.com Copyright ©2017 Cengage Learning. All Rights Reserved. May not be scanned, copied 17 or duplicated, or posted to a publicly accessible website, in whole or in part.  User Productivity Systems ◦ Technology that improves productivity ◦ Groupware: Enables data sharing and coordination of efforts  Systems Integration ◦ Combination of transaction processing, business support, knowledge management, and user productivity features Copyright ©2017 Cengage Learning. All Rights Reserved. May not be scanned, copied 18 or duplicated, or posted to a publicly accessible website, in whole or in part. FIGURE 1-14 A typical organizational model identifies business functions and organizational levels. Copyright ©2017 Cengage Learning. All Rights Reserved. May not be scanned, copied 19 or duplicated, or posted to a publicly accessible website, in whole or in part.  Top Managers ◦ Use IT to develop long-range strategic plans  Require information such as economic forecasts, technology trends, competitive threats, and governmental issues  Middle Managers and Knowledge Workers ◦ Middle managers provide direction, resources, and performance feedback to supervisors and team leaders  Require more detailed information than top managers ◦ Knowledge workers provide support for the organization’s basic functions Copyright ©2017 Cengage Learning. All Rights Reserved. May not be scanned, copied 20 or duplicated, or posted to a publicly accessible website, in whole or in part.  Supervisors and Team Leaders ◦ Oversee operational employees and carry out day- to-day functions  Require decision support information, knowledge management systems, and user productivity systems  Operational Employees ◦ Rely on TP systems to enter and receive data they need to perform their jobs ◦ Empowered to handle tasks and make decisions that were assigned previously to supervisors Copyright ©2017 Cengage Learning. All Rights Reserved. May not be scanned, copied 21 or duplicated, or posted to a publicly accessible website, in whole or in part.  Modeling ◦ Graphical representation of a concept or process  Business model  Data model  Object model  Network model  Process model FIGURE 1-15 Microsoft Visio allows you to drag and drop various symbols and connect them to show a business process. Source: Microsoft Visio 2010 Copyright ©2017 Cengage Learning. All Rights Reserved. May not be scanned, copied 22 or duplicated, or posted to a publicly accessible website, in whole or in part.  Prototyping ◦ Early working version of an information system  Disadvantage - Important decisions might be made before business or IT issues are thoroughly understood ◦ A prototype based on careful fact-finding and modeling techniques can be an extremely valuable tool Copyright ©2017 Cengage Learning. All Rights Reserved. May not be scanned, copied 23 or duplicated, or posted to a publicly accessible website, in whole or in part.  Computer-Aided Systems Engineering (CASE) Tools ◦ Known as computer-aided software engineering ◦ Provide an overall framework for systems development ◦ Support design methodologies  Structured analysis  Object-oriented analysis ◦ Generate program code  Speeds the implementation process Copyright ©2017 Cengage Learning. All Rights Reserved. May not be scanned, copied 24 or duplicated, or posted to a publicly accessible website, in whole or in part. Structured Object-Oriented Analysis (O-O) Analysis Agile/Adaptive Methods Copyright ©2017 Cengage Learning. All Rights Reserved. May not be scanned, copied 25 or duplicated, or posted to a publicly accessible website, in whole or in part.  Structured Analysis ◦ Time-tested and easy to understand ◦ Uses the systems development life cycle (SDLC) ◦ Based on predictive approach ◦ Process-centered technique  Uses process models to graphically describe a system FIGURE 1-18 This Visible Analyst screen shows a process model for a school registration system. The REGISTER STUDENTS process accepts input data from two sources and transforms it into output data. Source: Visible Systems Corporation Copyright ©2017 Cengage Learning. All Rights Reserved. May not be scanned, copied 26 or duplicated, or posted to a publicly accessible website, in whole or in part. ◦ Addresses data organization and structure, relational database design, and user interface issues ◦ The SDLC describes activities and functions that all systems developers perform, regardless of which approach they use Copyright ©2017 Cengage Learning. All Rights Reserved. May not be scanned, copied 27 or duplicated, or posted to a publicly accessible website, in whole or in part.  FIGURE 1-19 Development phases and deliverables are shown in the waterfall model. The circular symbols indicate interaction among the phases. Copyright ©2017 Cengage Learning. All Rights Reserved. May not be scanned, copied 28 or duplicated, or posted to a publicly accessible website, in whole or in part.  Steps in the SDLC Model ◦ Systems planning  Initiated by a systems request  Goal - To perform a preliminary investigation  Feasibility study: Reviews anticipated costs and benefits and recommends a course of action ◦ Systems analysis  Goal – To build a logical model of the new system  Requirements modeling: Analyst investigates business processes and documents the functions to be performed by the new system  Deliverable - System requirements document Copyright ©2017 Cengage Learning. All Rights Reserved. May not be scanned, copied 29 or duplicated, or posted to a publicly accessible website, in whole or in part. ◦ Systems design  Goal – To create a physical model that satisfies all documented requirements  User interface is designed and application architecture is determined  Outputs, inputs, and processes are identified  Deliverable - System design specification  Management and user involvement is critical Copyright ©2017 Cengage Learning. All Rights Reserved. May not be scanned, copied 30 or duplicated, or posted to a publicly accessible website, in whole or in part. ◦ Systems implementation  New system is constructed, programs are written, tested, and documented, and the system is installed  Deliverable - A completely functional and documented information system  Includes systems evaluation ◦ Systems support and security  IT staff maintains, enhances, and protects the system  A well-designed system must be secure, reliable, maintainable, and scalable Copyright ©2017 Cengage Learning. All Rights Reserved. May not be scanned, copied 31 or duplicated, or posted to a publicly accessible website, in whole or in part.  Object-Oriented Analysis ◦ Combines data and the processes that act on the data into objects  Object: Member of a class, which possesses properties  O-O methodology provides easy transition to O-O programming FIGURE 1-20 The PERSON class includes languages like Java INSTRUCTOR and STUDENT objects, which have their own properties and inherited properties. Copyright ©2017 Cengage Learning. All Rights Reserved. May not be scanned, copied 32 or duplicated, or posted to a publicly accessible website, in whole or in part.  FIGURE 1-21 In a typical O-O development model, planning, analysis, and design tasks interact continuously to generate prototypes that can be tested. Copyright ©2017 Cengage Learning. All Rights Reserved. May not be scanned, copied 33 or duplicated, or posted to a publicly accessible website, in whole or in part.  Agile Methods ◦ Involve building and constantly adjusting a series of prototypes to user requirements ◦ Use a spiral model  Spiral model: Series of iterations based on user feedback  Feedback from prior steps is incorporated in each incremental step ◦ Allow developers to be more flexible and responsive Copyright ©2017 Cengage Learning. All Rights Reserved. May not be scanned, copied 34 or duplicated, or posted to a publicly accessible website, in whole or in part.  ◦ Disadvantages  Riskier than traditional methods  Weak documentation and blurred lines of accountability  Lack of emphasis on the larger business picture  Other Development Methods ◦ Joint application development (JAD)  Focuses on team-based fact-finding ◦ Rapid application development (RAD)  A compressed version of the entire development process Copyright ©2017 Cengage Learning. All Rights Reserved. May not be scanned, copied 35 or duplicated, or posted to a publicly accessible website, in whole or in part. FIGURE 1-23 Depending on its size, an IT department might have separate organizational units for these functions, or they might be combined into a smaller number of teams. Copyright ©2017 Cengage Learning. All Rights Reserved. May not be scanned, copied 36 or duplicated, or posted to a publicly accessible website, in whole or in part.  Application Development ◦ Systems are developed by teams consisting of users, managers, and IT staff members  Systems Support and Security ◦ Provides vital protection and maintenance services  User Support ◦ Provides users with technical information, training, and productivity support  Known as a help desk Copyright ©2017 Cengage Learning. All Rights Reserved. May not be scanned, copied 37 or duplicated, or posted to a publicly accessible website, in whole or in part.  Database Administration ◦ Involves data design, management, security, backup, and access systems  Network Administration ◦ Includes hardware and software maintenance, support, and security  Web Support ◦ Web support specialists design and construct Web pages  Monitor traffic and manage hardware and software  Link Web-based applications information systems to the company’s information systems Copyright ©2017 Cengage Learning. All Rights Reserved. May not be scanned, copied 38 or duplicated, or posted to a publicly accessible website, in whole or in part.  Quality Assurance (QA) ◦ QA team reviews and tests all applications and systems changes to verify specifications and software quality standards Copyright ©2017 Cengage Learning. All Rights Reserved. May not be scanned, copied 39 or duplicated, or posted to a publicly accessible website, in whole or in part.  Investigates, analyzes, designs, develops, installs, evaluates, and maintains a company’s information systems  Constantly interacts with users and managers within and outside the organization Copyright ©2017 Cengage Learning. All Rights Reserved. May not be scanned, copied 40 or duplicated, or posted to a publicly accessible website, in whole or in part.  Roles ◦ Acts a translators to managers and programmers ◦ A company’s best line of defense in an IT disaster ◦ Most valuable skill - The ability to listen ◦ Seeks feedback from users to ensure that systems do not deviate from accomplishing set objectives  Knowledge, Skills, and Education ◦ Technical knowledge ◦ Communication and business skills ◦ Critical thinking skills Copyright ©2017 Cengage Learning. All Rights Reserved. May not be scanned, copied 41 or duplicated, or posted to a publicly accessible website, in whole or in part.  ◦ Education - A college degree in information systems, science, or business  Some IT experience is required  Certification ◦ Helps IT professionals learn new skills and gain recognition for their efforts Copyright ©2017 Cengage Learning. All Rights Reserved. May not be scanned, copied 42 or duplicated, or posted to a publicly accessible website, in whole or in part.  Career Opportunities ◦ Companies will need systems analysts to apply new information technology ◦ Explosion in e-commerce will fuel IT job growth ◦ Important factors  Job titles  Company organization  Company size  Salary, location and future Growth  Corporate culture Copyright ©2017 Cengage Learning. All Rights Reserved. May not be scanned, copied 43 or duplicated, or posted to a publicly accessible website, in whole or in part.  IT is one of the fastest evolving industries  Knowledge of current trends is vital to a systems analyst  Key trends ◦ Agile methods ◦ Cloud computing ◦ Mobile devices and apps ◦ IT firms now offer a mix of products, services, and support ◦ Social media Copyright ©2017 Cengage Learning. All Rights Reserved. May not be scanned, copied 44 or duplicated, or posted to a publicly accessible website, in whole or in part.  IT - Combination of hardware and software resources ◦ Used by companies to manage, access, communicate, and share information  Essential components of an information system ◦ Hardware, software, data, processes, and people  Successful companies offer a mix of products, technical and financial services, consulting, and customer support Copyright ©2017 Cengage Learning. All Rights Reserved. May not be scanned, copied 45 or duplicated, or posted to a publicly accessible website, in whole or in part.  Types of information systems ◦ Enterprise computing systems, transaction processing systems, business support systems, knowledge management systems, or user productivity systems  Organization structure includes top managers, middle managers and knowledge workers, supervisors and team leaders, and operational employees Copyright ©2017 Cengage Learning. All Rights Reserved. May not be scanned, copied 46 or duplicated, or posted to a publicly accessible website, in whole or in part.  Systems analysts use modelling, prototyping, and computer-aided systems engineering (CASE) tools  Popular system development approaches ◦ Structured analysis, object-oriented analysis, and agile methods  In addition to technical knowledge, a systems analyst must understand the business, think critically, and communicate effectively Copyright ©2017 Cengage Learning. All Rights Reserved. May not be scanned, copied 47 or duplicated, or posted to a publicly accessible website, in whole or in part.