SYSTEMS ANALYSIS AND DESIGN Seventh Edition THOMSON COURSE TECHNOLOGY 25 THOMSON PLACE BOSTON MA 02210 Australia • Canada • Denmark • Japan • Mexico • New Zealand • Philippines • Puerto Rico • Singapore South Africa • Spain • United Kingdom • United States Gary B. Shelly Thomas J. Cashman Harry J. Rosenblatt Executive Editor: Alexandra Arnold Senior Product Manager: Reed Curry Associate Product Manager: Klenda Martinez Editorial Assistant: Jon Farnham Print Buyer: Julio Esperas Senior Content Project Manager: Philippa Lehar Production Assistant: Stephen Greenfield Development Editor: Deb Kaufmann Proofreader: Green Pen Quality Assurance Art Director: Bruce Bond Interior and Text Design: Joel Sadagursky Cover Photos: Jon Chomitz Compositor: GEX Publishing Services Indexer: Rich Carlson Printer: Courier Kendalville COPYRIGHT © 2008 Thomson Course Technology, a division of Thomson Learning, Inc. Thomson Learning™ is a trademark used herein under license. 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All other names used herein are for identification pur- poses only and are trademarks of their respec- tive owners. Thomson Course Technology reserves the right to revise this publication and make changes from time to time in its content with- out notice. ISBN-13: 978-1-4239-1222-4 ISBN-10: 1-4239-1222-5 Systems Analysis and Design Seventh Edition Gary B. Shelly Thomas J. Cashman Harry J. Rosenblatt BRIEF CONTENTS Chapter 1 Introduction to Systems Analysis and Design 2 PHASE 1: SYSTEMS PLANNING 45 Chapter 2 Analyzing the Business Case 46 PHASE 2: SYSTEMS ANALYSIS 91 Chapter 3 Requirements Modeling 92 Chapter 4 Data and Process Modeling 148 Chapter 5 Object Modeling 196 Chapter 6 Development Strategies 232 PHASE 3: SYSTEMS DESIGN 281 Chapter 7 Output and User Interface Design 282 Chapter 8 Data Design 338 Chapter 9 System Architecture 398 PHASE 4: SYSTEMS IMPLEMENTATION 447 Chapter 10 Systems Implementation 448 PHASE 5: SYSTEMS OPERATION, SUPPORT, AND SECURITY 505 Chapter 11 Systems Operation, Support, and Security 506 THE SYSTEMS ANALYST’S TOOLKIT 559 Toolkit 1 Communication Tools 560 Toolkit 2 CASE Tools 578 Toolkit 3 Financial Analysis Tools 596 Toolkit 4 Project Management Tools 616 Toolkit 5 Internet Resource Tools 646 Glossary/Index 674 iii iv Objectives 2 Introduction 2 The Impact of Information Technology 4 The Future of IT 4 The Role of Systems Analysis and Design 4 Who Develops Information Systems? 5 Information System Components 5 Hardware 6 Software 6 Data 7 Processes 7 People 7 Understanding the Business 8 Business Profile 8 Business Models 8 New Kinds of Companies 9 Case in Point 1.1: Cloud Nine Financial Advisors 9 Impact of the Internet 9 B2C (Business-to-Consumer) 10 B2B (Business-to-Business) 10 Web-Based System Development 11 How Business Uses Information Systems 12 Enterprise Computing Systems 12 Transaction Processing Systems 12 Business Support Systems 13 Knowledge Management Systems 14 User Productivity Systems 14 Information Systems Integration 14 Information System Users and Their Needs 15 Top Managers 15 Middle Managers and Knowledge Workers 15 Supervisors and Team Leaders 16 Operational Employees 16 Systems Development Tools and Techniques 16 Modeling 16 Prototyping 17 Computer-Aided Systems Engineering (CASE) Tools 17 Systems Development Methods 18 Structured Analysis 18 Object-Oriented Analysis 19 Planning and Modeling a Systems Development Project 19 Comparison of Predictive and Adaptive Models 20 The SDLC Waterfall Model 20 Adaptive Methods and Models 23 Joint Application Development and Rapid Application Development Methods and Models 24 Other Development Methods and Models 24 The Importance of Project Management 24 Systems Development Guidelines 25 Planning 25 Involve the Users Throughout the Development Process 25 Listening Is Very Important 25 Use Project Management Tools to Identify Tasks and Milestones 25 Remain Flexible 25 Develop Accurate Cost and Benefit Information 25 Information Technology Department 26 Application Development 26 Systems Support and Security 26 Case in Point 1.2: Global Hotels and Momma’s Motels 27 User Support 27 Database Administration 27 Network Administration 27 Web Support 27 Quality Assurance (QA) 28 Case in Point 1.3: What Should Lisa Do? 28 The Systems Analyst Position 28 Responsibilities 28 Required Skills and Background 28 Certification 29 Career Opportunities 29 Case in Point 1.4: Just-in-Time Airfreight, Inc. 30 Chapter Summary 30 Key Terms and Phrases 32 Learn It Online 33 Case-Sim: SCR Associates 34 Chapter Exercises 35 Apply Your Knowledge 36 Case Studies 38 New Century Health Clinic 38 Personal Trainer, Inc. 39 Original Kayak Adventures 40 Chapter Capstone Case: SoftWear, Limited 42 PHASE 1: SYSTEMS PLANNING Objectives 46 Introduction 46 Strategic Planning — A Framework for IT Systems Development 48 Strategic Planning Overview 48 From Strategic Plans to Business Results 49 Case in Point 2.1: Lo Carb Meals 51 A Business Example 51 The Role of the IT Department in Project Evaluation 51 The Future 52 Case in Point 2.2: Attaway Airlines, Part One 53 What is a Business Case? 53 Information Systems Projects 54 Main Reasons for Systems Projects 54 Case in Point 2.3: Trent College 56 Factors that Affect Systems Projects 56 Internal Factors 57 External Factors 57 Project Management Tools 59 Risk Management 59 TABLE OF CONTENTS Chapter 1 Introduction to Systems Analysis and Design Chapter 2 Analyzing the Business Case Table of Contents Evaluation of Systems Requests 60 Systems Request Forms 60 Systems Review Committee 61 Overview of Feasibility 61 Operational Feasibility 62 Technical Feasibility 62 Economic Feasibility 63 Schedule Feasibility 64 Evaluating Feasibility 64 Setting Priorities 64 Factors that Affect Priority 65 Discretionary and Nondiscretionary Projects 65 Case in Point 2.4: Attaway Airlines, Part Two 66 Preliminary Investigation Overview 66 Interaction with Managers and Users 66 Planning the Preliminary Investigation 67 Step 1: Understand the Problem or Opportunity 68 Step 2: Define the Project Scope and Constraints 69 Step 3: Perform Fact-Finding 71 Step 4: Evaluate Feasibility 72 Step 5: Estimate Project Development Time and Cost 73 Step 6: Present Results and Recommendations to Management 73 Chapter Summary 74 Key Terms and Phrases 75 Learn It Online 76 Case-Sim: SCR Associates 77 Chapter Exercises 78 Apply Your Knowledge 79 Case Studies 81 New Century Health Clinic 81 Personal Trainer, Inc. 81 Original Kayak Adventures 82 Town of Eden Bay 83 Chapter Capstone Case: SoftWear, Limited 85 PHASE 2: SYSTEMS ANALYSIS Objectives 92 Introduction 92 Systems Analysis Phase Overview 94 Systems Analysis Activities 94 Systems Analysis Skills 95 Team-Oriented Methods and Techniques 95 Joint Application Development 95 User Involvement 95 JAD Participants and Roles 96 JAD Advantages and Disadvantages 97 Rapid Application Development 97 RAD Phases and Activities 98 RAD Objectives 98 RAD Advantages and Disadvantages 99 Case in Point 3.1: North Hills College 100 Modeling Tools and Techniques 100 CASE Tools 100 Functional Decomposition Diagrams 100 Data Flow Diagrams 101 Unified Modeling Language 101 System Requirements Checklist 103 Output Examples 103 Input Examples 104 Process Examples 104 Performance Examples 104 Control Examples 104 Future Growth, Costs, and Benefits 105 Scalability 105 Total Cost of Ownership 105 Fact-Finding 106 Fact-Finding Overview 106 Who,What,Where,When, How, and Why? 107 The Zachman Framework 108 Interviews 109 Step 1: Determine the People to Interview 109 Step 2: Establish Objectives for the Interview 109 Step 3: Develop Interview Questions 110 Step 4: Prepare for the Interview 111 Step 5: Conduct the Interview 112 Step 6: Document the Interview 112 Step 7: Evaluate the Interview 113 Case in Point 3.2: Deep River College 113 Unsuccessful Interviews 113 Case in Point 3.3: FastPak Overnight Package System 114 Other Fact-Finding Techniques 114 Document Review 114 Observation 114 Questionnaires and Surveys 116 Sampling 117 Research 118 Interviews versus Questionnaires 120 Case in Point 3.4: CyberStuff 120 Documentation 121 The Need for Recording the Facts 121 Software Tools 121 Preview of Logical Modeling 125 Chapter Summary 125 Key Terms and Phrases 126 Learn It Online 127 Case-Sim: SCR Associates 128 Chapter Exercises 129 Apply Your Knowledge 130 Case Studies 132 New Century Health Clinic 132 Personal Trainer, Inc. 133 Baxter Community College 134 Town of Eden Bay 134 Chapter Capstone Case: SoftWear, Limited 135 Objectives 148 Introduction 148 v Chapter 3 Requirements Modeling Chapter 4 Data and Process Modeling vi Overview of Data and Process Modeling Tools 150 Data Flow Diagrams 150 DFD Symbols 150 Creating a Set of DFDs 156 Guidelines for Drawing DFDs 156 Step 1: Draw a Context Diagram 157 Step 2: Draw a Diagram 0 DFD 159 Step 3: Draw the Lower-Level Diagrams 162 Case in Point 4.1: Big Ten University 167 Data Dictionary 167 Documenting the Data Elements 168 Documenting the Data Flows 169 Documenting the Data Stores 170 Documenting the Processes 171 Documenting the Entities 172 Documenting the Records 172 Data Dictionary Reports 172 Process Description Tools 173 Modular Design 173 Structured English 174 Decision Tables 175 Case in Point 4.2: Rock Solid Outfitters (Part 1) 177 Decision Trees 177 Case in Point 4.3: Rock Solid Outfitters (Part 2) 178 Logical Versus Physical Models 178 Sequence of Models 178 Four-Model Approach 178 Case in Point 4.4: Tip Top Staffing 179 Chapter Summary 179 Key Terms and Phrases 180 Learn It Online 181 Case-Sim: SCR Associates 182 Chapter Exercises 183 Apply Your Knowledge 184 Case Studies 186 New Century Health Clinic 186 Personal Trainer, Inc. 187 Chapter Capstone Case: SoftWear, Limited 188 Objectives 196 Introduction 196 Object-Oriented Terms and Concepts 198 Overview of O-O Analysis 198 Objects 199 Attributes 201 Methods 202 Messages 203 Classes 204 Relationships Among Objects and Classes 206 Object Relationship Diagram 206 Object Modeling with the Unified Modeling Language 207 Use Case Modeling 207 Case in Point 5.1: Hilltop Motors 209 Use Case Diagrams 209 Class Diagrams 210 Case in Point 5.2: Train the Trainer, Inc. 212 Sequence Diagrams 212 State Transition Diagrams 213 Activity Diagrams 214 Case in Point 5.3: Travel Biz 214 CASE Tools 214 Organizing the Object Model 215 Case in Point 5.4: Cyber Associates 215 Chapter Summary 215 Key Terms and Phrases 216 Learn It Online 217 Case-Sim: SCR Associates 218 Chapter Exercises 219 Apply Your Knowledge 220 Case Studies 222 New Century Health Clinic 222 Personal Trainer, Inc. 222 Chapter Capstone Case: SoftWear, Limited 223 Objectives 232 Introduction 232 Development Strategies Overview 234 The Impact of the Internet 234 Software as a Service 234 Traditional vs.Web-Based Systems Development 235 Outsourcing 237 The Growth of Outsourcing 237 Outsourcing Fees 238 Outsourcing Issues and Concerns 239 Offshore Outsourcing 240 Case in Point 6.1: Turnkey Services 241 In-House Software Development Options 241 Make or Buy Decision 241 Developing Software In-House 242 Purchasing a Software Package 243 Customizing a Software Package 244 Creating User Applications 245 Role of the Systems Analyst 246 Analyzing Cost and Benefits 247 Financial Analysis Tools 247 Case in Point 6.2: Sterling Associates 247 Cost-Benefit Analysis Checklist 248 The Software Acquisition Process 249 Step 1: Evaluate the Information System Requirements 249 Step 2: Identify Potential Vendors or Outsourcing Options 252 Step 3: Evaluate the Alternatives 254 Step 4: Perform Cost-Benefit Analysis 255 Step 5: Prepare a Recommendation 255 Step 6: Implement the Solution 256 Table of Contents Chapter 5 Object Modeling Chapter 6 Development Strategies Table of Contents Case in Point 6.3: Doug’s Sporting Goods 256 Completion of Systems Analysis Tasks 257 System Requirements Document 257 Presentation to Management 257 The Transition to Systems Design 258 Preparing for Systems Design Tasks 258 The Relationship between Logical and Physical Design 259 Systems Design Guidelines 259 Systems Design Objectives 260 Case in Point 6.4: Downtown! 262 Design Trade-Offs 263 Prototyping 264 Prototyping Methods 264 Prototyping Tools 265 Limitations of Prototypes 266 Future Trends In Software Development 266 Chapter Summary 267 Key Terms and Phrases 269 Learn It Online 270 Case-Sim: SCR Associates 271 Chapter Exercises 272 Apply Your Knowledge 273 Case Studies 275 New Century Health Clinic 275 Personal Trainer, Inc. 276 Cutting Edge 277 Chapter Capstone Case: SoftWear, Limited 278 PHASE 3: SYSTEMS DESIGN Objectives 282 Introduction 282 Output Design 284 Types of Output 284 Printed and Screen Output 287 Reports 287 User Involvement in Report Design 289 Report Design Principles 290 Report Design Issues 292 Designing Character-Based Reports 293 Case in Point 7.1: Lazy Eddie 293 Printing Volume and Time Requirements 294 Output Control and Security 296 User Interface Design 297 Evolution of the User Interface 297 Human-Computer Interaction 299 Case in Point 7.2: Casual Observer Software 301 Basic Principles of User-Centered Design 303 Guidelines for User Interface Design 304 User Interface Controls 310 Case in Point 7.3: Trustworthy Insurance Company 312 Input Design 312 Input and Data Entry Methods 312 Input Volume 314 Designing Data Entry Screens 315 Input Errors 317 Source Documents 318 Input Control 320 Case in Point 7.4: Boolean Toys 321 Chapter Summary 321 Key Terms and Phrases 323 Learn It Online 324 Case-Sim: SCR Associates 325 Chapter Exercises 326 Apply Your Knowledge 327 Case Studies 329 New Century Health Clinic 329 Personal Trainer, Inc. 329 Video Superstore 330 Chapter Capstone Case: SoftWear, Limited 331 Objectives 338 Introduction 338 Data Design Concepts 340 Data Structures 340 Overview of File Processing 341 The Evolution from File Systems to Database Systems 342 Some Database Tradeoffs 343 Dbms Components 344 Interfaces for Users, Database Administrators, and Related Systems 345 Data Manipulation Language 345 Schema 345 Physical Data Repository 346 Web-Based Database Design 346 Characteristics of Web-Based Design 347 Internet Terminology 347 Connecting a Database to the Web 348 Data Security 349 Data Design Terminology 349 Definitions 349 Key Fields 350 Referential Integrity 352 Entity-Relationship Diagrams 353 Drawing an ERD 354 Types of Relationships 354 Cardinality 356 Case in Point 8.1: TopText Publishing 358 Normalization 358 Standard Notation Format 359 Repeating Groups and Unnormalized Designs 359 First Normal Form 360 Second Normal Form 361 Third Normal Form 363 A Normalization Example 365 Case in Point 8.2: CyberToys 367 Using Codes During Data Design 369 Overview of Codes 369 Types of Codes 370 Developing a Code 371 Case in Point 8.3: DotCom Tools 373 vii Chapter 7 Output and User Interface Design Chapter 8 Data Design viii Steps in Database Design 373 Database Models 374 Relational Databases 374 Object-Oriented Databases 377 Data Storage and Access 377 Strategic Tools for Data Storage and Access 377 Logical and Physical Storage 379 Data Storage Formats 380 Selecting a Data Storage Format 381 Date Fields 382 Data Control 382 Case in Point 8.4: SoccerMom 383 Chapter Summary 384 Key Terms and Phrases 386 Learn It Online 387 Case-Sim: SCR Associates 388 Chapter Exercises 389 Apply Your Knowledge 390 Case Studies 392 New Century Health Clinic 392 Personal Trainer, Inc. 392 FastFlight Airlines 392 Chapter Capstone Case: SoftWear, Limited 394 Objectives 398 Introduction 398 System Architecture Checklist 400 Enterprise Resource Planning 400 Case in Point 9.1: ABC Systems 401 Initial Cost and TCO 401 Scalability 402 Web Integration 403 Legacy System Interface Requirements 403 Processing Options 404 Security Issues 404 Planning the Architecture 404 Servers 405 Clients 406 Client/Server Architecture 407 Overview 407 Client/Server Design Styles 409 Types of Clients: Fat and Thin 410 Client/Server Tiers 410 Middleware 411 Cost-Benefit Issues 411 Client/Server Performance Issues 412 Internet-Based Architecture 413 Developing E-Commerce Solutions In-House 414 Case in Point 9.2: Small Potatoes, Inc. 415 Packaged Solutions and E-Commerce Service Providers 415 Corporate Portals 416 Processing Methods 418 Online Processing 418 Batch Processing 419 Case in Point 9.3: R/Way Trucking Company 419 Combined Online and Batch Processing 419 Network Models 420 The OSI Reference Model 420 Network Modeling Tools 421 Network Topology 421 Network Protocols and Licensing Issues 424 Wireless Networks 424 Case in Point 9.4: Spider IT Services 426 System Management and Support 426 Performance Management 426 Fault Management, Backup, and Disaster Recovery 426 Systems Design Completion 430 System Design Specification 430 User Approval 431 Presentations 432 Chapter Summary 432 Key Terms and Phrases 435 Learn It Online 436 Case-Sim: SCR Associates 437 Chapter Exercises 438 Apply Your Knowledge 439 Case Studies 441 New Century Health Clinic 441 Personal Trainer, Inc. 441 Chapter Capstone Case: SoftWear, Limited 443 PHASE 4: SYSTEMS IMPLEMENTATION Objectives 448 Introduction 448 Software Quality Assurance 450 Software Engineering 450 International Organization for Standardization (ISO) 451 Overview of Application Development 453 Creation of the System Design 453 Application Development Steps 453 Project Management 454 Structured Application Development 454 Structure Charts 454 Cohesion and Coupling 455 Drawing a Structure Chart 457 Other Structured Development Tools 460 Object-Oriented Application Development 461 Object-Oriented Application Development Compared to Structured Development 461 Implementation of Object-Oriented Designs 462 Coding 463 Programming Environments 463 Generating Code 463 Testing the System 463 Unit Testing 464 Table of Contents Chapter 9 System Architecture Chapter 10 Systems Implementation Table of Contents Case in Point 10.1: Your Move, Inc. 465 Integration Testing 465 System Testing 466 Case in Point 10.2: WebTest, Inc. 467 Documentation 467 Program Documentation 468 System Documentation 468 Operations Documentation 469 User Documentation 470 Management Approval 474 System Installation and Evaluation 474 Operational and Test Environments 474 Training 475 Training Plan 476 Vendor Training 477 Webinars and Podcasts 477 Outside Training Resources 478 In-House Training 478 Data Conversion 482 Data Conversion Strategies 482 Data Conversion Security and Controls 482 System Changeover 482 Direct Cutover 483 Parallel Operation 483 Pilot Operation 484 Phased Operation 484 Case in Point 10.3: Global Cooling 485 Post-Implementation Tasks 485 Post-Implementation Evaluation 485 Case in Point 10.4: Yorktown Industries 487 Final Report to Management 488 Chapter Summary 488 Key Terms and Phrases 490 Learn It Online 491 Case-Sim: SCR Associates 492 Chapter Exercises 493 Apply Your Knowledge 494 Case Studies 496 New Century Health Clinic 496 Personal Trainer, Inc. 496 Fanciful Crystal 497 Chapter Capstone Case: SoftWear, Limited 498 PHASE 5: SYSTEMS OPERATION, SUPPORT,AND SECURITY Objectives 506 Introduction 506 Overview of Systems Support and Maintenance 508 User Support Activities 508 User Training 508 Help Desks 508 Online Chat Support 509 Maintenance Activities 510 Corrective Maintenance 512 Adaptive Maintenance 513 Perfective Maintenance 513 Preventive Maintenance 514 Case in Point 11.1: Outback Outsourcing, Inc. 515 Managing System Support 515 Maintenance Team 515 Case in Point 11.2: Brightside Insurance, Inc. 517 Managing Maintenance Requests 517 Establishing Priorities 519 Configuration Management 519 Maintenance Releases 519 Version Control 521 Baselines 522 Managing System Performance 522 Performance and Workload Measurement 523 Capacity Planning 525 System Maintenance Tools 527 System Security 528 Physical Security 528 Case in Point 11.3: Outer Banks County 531 Network Security 532 Application Security 534 File Security 536 User Security 536 Case in Point 11.4: Chain Link Consulting, Inc. 539 Data Backup and Recovery 540 Backup Options 540 Disaster Recovery Issues 541 System Obsolescence 541 Facing the Future: Challenges and Opportunities 542 Predictions 543 Strategic Planning for IT Professionals 544 IT Credentials and Certification 544 Chapter Summary 545 Key Terms and Phrases 547 Learn It Online 548 Case-Sim: SCR Associates 549 Chapter Exercises 550 Apply Your Knowledge 551 Case Studies 553 New Century Health Clinic 553 Personal Trainer, Inc. 553 Tarheel Industries 554 Mills Imports 555 Chapter Capstone Case: SoftWear, Limited 556 THE SYSTEMS ANALYST’S TOOLKIT Objectives 560 Introduction 560 ix Chapter 11 Systems Operation, Support, and Security Toolkit 1 Communication Tools