Data Communications & Computer Networks: A Business User’s Approach, Ninth Edition
Jill West & Curt M. White
Contents
Chapter 1
Introduction to Data Communications and Computer Networks 1
1-1: The Language of Computer
Networking 3
Remember this… 4
Self-check 4
1-2: The Big Picture of Networks 5
Remember this… 6
Self-check 6
1-3: Common Network Examples 6
The Desktop Computer and the Internet 6
A Laptop Computer and a Wireless Connection 8
Cellular Network 9
Other Common Network Systems 9
Sensor Networks 10
Business Mainframe Network 11
Satellite Networks 11
Cloud Networks 11
Remember this… 13
Self-check 13
1-4: Network Architectures 14
The TCP/IP Protocol Suite 14
Application Layer 16
Transport Layer 16
Network Layer 16
Data Link Layer 16
Physical Layer 17
The OSI Model 17
Logical and Physical Connections 18
The TCP/IP Protocol Suite in Action 19
Remember this… 22
Self-check 22
1-5: Cloud Computing 22
Cloud Computing Characteristics 22
Cloud Service Models 24
Remember this… 26
Self-check 26
Summary 27
Key Terms 28
Review Questions 29
Hands-On Project 1 31
Reflection Discussion 1 33
Solutions to Self-Check Questions 34
Chapter 2
Conducted and Radiated Media 37
2-1: Cabling Standards 38
Personal Area Network (PAN) Connection Standards 39
Universal Serial Bus (USB) 39
Thunderbolt 40
Lightning 41
Remember this… 41
Self-check 42
2-2: Conducted Media 42
Twisted Pair Cable 42
Types of Twisted Pair Cable 43
Unshielded and Shielded Twisted Pair 45
Coaxial Cable 47
Fiber-Optic Cable 48
Cable Connectors 51
Twisted Pair Cable Connectors 51
Coaxial Connectors 51
Fiber Connectors 52
Summary of Wired LAN Technologies 53
Remember this… 54
Self-check 54
2-3: Radiated Media on LANs 54
Wi-Fi 55
Wireless LAN Standards 57
Bluetooth 58
Zigbee 59
Other Wireless Technologies in a LAN Environment 60
Infrared (IR) 60
Ultra-Wideband (UWB) 61
Near-Field Communication (NFC) 61
Summary of Wireless LAN Technologies 62
Remember this… 62
Self-check 63
2-4: Media Selection Criteria 63
Cost 63
Speed 64
Expandability and Distance 64
Environment 65
Security 65
Remember this… 65
Self-check 65
Summary 66
Key Terms 67
Review Questions 68
Hands-On Project 2 70
Reflection Discussion 2 71
Solutions to Self-Check Questions 72
Chapter 3
Fundamentals of Data and Signals 74
3-1: Data and Signals 75
Analog vs. Digital 75
Analog Data and Signals 76
Digital Data and Signals 77
Fundamentals of Signals 79
Remember this… 83
Self-check 83
3-2: Converting Data into Signals 83
Transmitting Analog Data with Analog Signals 83
Transmitting Digital Data with Square-Wave Digital
Signals: Digital Encoding Schemes 84
Nonreturn to Zero Digital Encoding Schemes 84
Manchester Code Digital Encoding Schemes 85
4B/5B Digital Encoding Scheme 86
Transmitting Digital Data with Discrete
Analog Signals 88
Amplitude Shift Keying 88
Frequency Shift Keying 89
Phase Shift Keying 89
Transmitting Analog Data with Digital Signals 92
Pulse Code Modulation 92
Delta Modulation 94
Remember this… 96
Self-check 97
3-3: Characters and Codes 97
ASCII 97
Unicode 97
Remember this… 99
Self-check 99
Summary 100
Key Terms 101
Review Questions 101
Hands-On Project 3 103
Reflection Discussion 3 105
Solutions to Self-Check Questions 106
Chapter 4
Frames and Errors 108
4-1: Data Link Frames 108
Data Link Responsibilities 109
Frame Components 109
Remember this… 110
Self-check 111
4-2: Noise and Errors 111
Gaussian Noise 111
Impulse Noise 112
Crosstalk 113
Echo 113
Jitter 114
Attenuation 114
Error Prevention 114
Remember this… 115
Self-check 116
4-3: Error Detection 116
Parity Checks 116
Simple Parity 116
Longitudinal Parity 117
Arithmetic Checksum 118
Cyclic Redundancy Check 120
Remember this… 121
Self-check 122
4-4: Error Control 122
Toss the Frame or Packet 122
Return the Message 122
Stop-and-Wait Error Control 122
Sliding Window Error Control 123
Correct the Error 126
Remember this… 129
Self-check 129
Summary 130
Key Terms 131
Review Questions 132
Hands-On Project 4 134
Reflection Discussion 4 138
Solutions to Self-Check Questions 139
Chapter 5
Wired and Wireless Local Area Networks 141
5-1: Using LANs 142
Putting LANs to Work 143
Advantages and Disadvantages of LANs 144
Remember this… 145
Self-check 145
5-2: Evolution of LAN Technologies 145
Bus Topology 145
Star-Wired Bus Topology 147
Contention-Based Protocols 148
Star Topology 149
Remember this… 150
Self-check 150
5-3: Switches 151
MAC (Medium Access Control) Addresses 151
Virtual LANs 154
Link Aggregation 155
Spanning Tree Algorithm 156
Quality of Service 157
Remember this… 158
Self-check 158
5-4: Wired LANs 158
Ethernet Standards 158
Wired Ethernet Frame Format 160
Remember this… 162
Self-check 163
5-5: Wireless LANs 163
Wireless CSMA/CA 163
CSMA/CA Frame Format 164
Remember this… 166
Self-check 166
Summary 166
Key Terms 168
Review Questions 168
Hands-On Project 5 170
Reflection Discussion 5 173
Solutions to Self-Check Questions 174
Chapter 6
Network Systems and Software 175
6-1: Network Servers and Software 175
RAID Configurations 176
Storage Types 178
Utilities 179
Software Licensing Models 180
Remember this… 182
Self-check 182
6-2: Server Operating Systems 183
Unix 183
Linux 183
Microsoft Windows Server 184
Remember this… 187
Self-check 187
6-3: Network Devices 187
Command Modes 187
Configuring with Commands 188
Remember this… 189
Self-check 189
6-4: Virtualization 190
Hypervisors 190
Advantages and Disadvantages of Virtualization 191
Virtualizing Network Devices 192
Software-Defined Networking (SDN) 193
Remember this… 194
Self-check 194
6-5: Cloud Computing 194
Popular Cloud Platforms 194
Service Categories 196
Pricing Strategies 197
Cloud Storage 198
Cloud-Native Storage 198
Storage Optimization 199
Cloud-Native Computing 200
Containerization 202
Serverless Computing 203
Remember this… 203
Self-check 204
Summary 204
Key Terms 206
Review Questions 206
Hands-On Project 6 208
Reflection Discussion 6 212
Solutions to Self-Check Questions 213
Chapter 7
The Internet 215
7-1: Internet Protocol (IP) 216
IP Packets 217
Internet Protocol Version 4 (IPv4) 218
IPv4 Addresses 219
Internet Protocol Version 6 (IPv6) 221
IPv6 Addresses 223
Remember this… 223
Self-check 223
7-2: Locating a Resource on the
Internet 223
Uniform Resource Locator (URL) 224
Domain Name System (DNS) 225
Dynamic Host Configuration Protocol (DHCP) 225
Network Address Translation (NAT) 226
Remember this… 228
Self-check 228
7-3: Protocols of the Internet 229
Transmission Control Protocol (TCP) 229
TCP Segment Format 229
User Datagram Protocol (UDP) 230
Address Resolution Protocol (ARP) 231
Internet Control Message Protocol (ICMP) 231
Remember this… 233
Self-check 233
7-4: Internet Services 233
Email 233
File Transfer Protocol (FTP) 234
Intranets and Extranets 236
Remote Login 236
Telnet 236
Secure Remote Login Protocols 237
Voice over IP (VoIP) 238
Media Streaming 240
The Internet of Things (IoT) 240
Data Analytics 242
Remember this… 243
Self-check 243
Summary 244
Key Terms 245
Review Questions 246
Hands-On Project 7 248
Reflection Discussion 7 251
Solutions to Self-Check Questions 253
Chapter 8
Risk, Security, and Compliance 255
8-1: Network Security Risks 256
Common Vulnerabilities and Attack Types 256
Compromise Users 256
Compromise Software 256
Compromise Availability 256
Compromise Accounts 257
Other Attack Strategies 257
Risk and Security Assessments 259
Risk Response 261
Security Policies 261
Incident Response 261
Remember this… 262
Self-check 262
8-2: Network Security Technologies 262
Physical Security 263
Prevention Methods 263
Detection Methods 263
Anti-Malware 264
Proxy Server 264
Access Control Lists (ACLs) 265
Firewalls 265
Firewall Effectiveness 265
Firewall Functionality in the Cloud 266
Firewall Limitations 267
Intrusion Detection and Prevention Systems 267
Remember this… 268
Self-check 269
8-3: Data Security Technologies 269
CIA Triad 269
Data Security Regulations and Compliance 270
Encryption 271
Monoalphabetic Substitution-Based Ciphers 272
Polyalphabetic Substitution-Based Ciphers 272
Transposition-Based Ciphers 273
DES (Data Encryption Standard) and AES
(Advanced Encryption Standard) 274
Public Key Cryptography 275
Public Key Infrastructure (PKI) 275
Technologies That Use Encryption 278
Digital Signatures 278
Tunneling Protocols 278
Remember this… 279
Self-check 279
8-4: IAM (Identity and Access
Management) 279
Access Rights 280
Authentication 280
Hashing 281
Blockchain 284
Single Sign-On (SSO) and Federated Identity
Management (FIM) 284
Authorization 285
Accounting 285
Remember this… 286
Self-check 287
8-5: Wireless Security 288
Securing Wireless LANs 288
Spread Spectrum Technology 288
Frequency Hopping Spread Spectrum 288
Direct Sequence Spread Spectrum 290
Remember this… 290
Self-check 290
Summary 291
Key Terms 293
Review Questions 294
Hands-On Project 8 295
Reflection Discussion 8 300
Solutions to Self-Check Questions 301
Chapter 9
Wide Area Networks 303
9-1: Networks That Connect LANs 304
Campus Area Networks (CANs) 304
Metropolitan Area Networks (MANs) 304
WAN Topology 305
Remember this… 306
Self-check 306
9-2: Routing 306
Best Paths 307
Dynamic Versus Static Routing 308
Routing Protocols 309
Routing Information Protocol (RIP) 309
Open Shortest Path First (OSPF) 311
Intermediate System to Intermediate
System (IS-IS) 311
Enhanced Interior Gateway Routing
Protocol (EIGRP) 311
Border Gateway Protocol (BGP) 311
Remember this… 312
Self-check 312
9-3: Multiplexing 312
Time Division Multiplexing (TDM) 313
Synchronous Time Division Multiplexing 313
Statistical Time Division Multiplexing 314
Frequency Division Multiplexing (FDM) 315
Wavelength Division Multiplexing (WDM) 316
Wi-Fi Multiplexing 316
Cellular Network Multiplexing 318
Global System for Mobile
Communications (GSM) 318
Code Division Multiplexing (CDM) 318
Orthogonal Frequency Division Multiplexing
(OFDM) 319
Remember this… 319
Self-check 320
9-4: Compression 320
Lossless Compression 320
Run-Length Encoding 321
Lempel-Ziv Technique 321
Lossy Compression 322
MP3 (MPEG [Moving Picture Experts
Group] Audio Layer-3) 322
JPEG (Joint Photographic Experts Group) 322
MPEG (Moving Picture Experts Group) 325
Remember this… 325
Self-check 326
Summary 326
Key Terms 328
Review Questions 329
Hands-On Project 9 330
Reflection Discussion 9 334
Solutions to Self-Check Questions 335
Chapter 10
Connecting Networks and Resources 336
10-1: Small Business and
Consumer-Grade WAN Services 337
Digital Subscriber Line (DSL) 337
DSL Basics 337
DSL Formats 339
Cable Modems 339
Fiber Internet 341
Satellite 342
Cellular Networks 344
Remember this… 346
Self-check 347
10-2: Enterprise-Grade WAN Services 347
Legacy WAN Technologies 347
MPLS 348
Ethernet 349
Virtual Private Network (VPN) 351
Cloud Connectivity 354
Remember this… 355
Self-check 355
10-3: WAN Virtualization 355
Software-Defined WAN (SD-WAN) 356
Software-Defined Branch (SD-Branch) 357
Secure Access Service Edge (SASE) 358
Remember this… 358
Self-check 358
10-4: Cloud-Supported Technologies 359
Digital Marketing 359
Remote Workers 360
Edge Computing 361
Remember this… 362
Self-check 362
Summary 363
Key Terms 365
Review Questions 365
Hands-On Project 10 367
Reflection Discussion 10 369
Solutions to Self-Check Questions 370
Chapter 11
Network Design and Management 372
11-1: Planning for Changes 373
Project Management 373
Application Lifecycle Management (ALM) 374
Change Management 376
Remember this… 378
Self-check 378
11-2: Analyzing Design 378
Network Modeling 378
Wide Area Connectivity Map 379
Metropolitan Area Connectivity Map 379
Local Area Connectivity Map 379
Gap Analysis 381
Feasibility Studies 381
Capacity Planning 382
Testing Environments 383
Remember this… 384
Self-check 385
11-3: Network Monitoring and
Management 385
Network Monitoring Tools 385
Monitoring Network Hardware 385
Monitoring Network Traffic 386
Alerts and Logs 387
Syslog 387
Simple Network Management
Protocol (SNMP) 388
NetFlow 389
Creating a Baseline 390
Remember this… 392
Self-check 393
11-4: Cloud Deployment and
Management 393
Cloud Migration 393
Migration Phases 394
Migration Strategies 395
Cloud Provisioning and Configuration
Management 396
Automation 396
Infrastructure as Code (IaC) 398
Automation and Orchestration Tools 399
Cloud Monitoring and Optimization 401
Remember this… 403
Self-check 403
Summary 404
Key Terms 406
Review Questions 406
Hands-On Project 11 408
Reflection Discussion 11 411
Solutions to Self-Check Questions 412
Chapter 12
Business Principles in IT 414
12-1: People Resources 415
Network Administrator Skills and Certifications 415
Professional Development 416
Training Users 418
Policies and Procedures 419
Remember this… 420
Self-check 420
12-2: Vendor Relations 420
Vendor Services 421
Support Plans 421
Time to Market 422
Managed Services 422
Vendor Lock-In 422
Vendor Documentation 423
Request for Information (RFI) 423
Statement of Work (SOW) 423
Service Level Agreement (SLA) 423
Project Evaluations 424
Remember this… 425
Self-check 425
12-3: Financial Aspects of Cloud 426
CapEx vs. OpEx 426
Tracking Cloud Expenses 427
Cloud Cost Optimization 428
Instance Pricing Options 429
Data Replication Cost vs. Benefit 430
Licensing in the Cloud 430
Remember this… 431
Self-check 432
12-4: Continuity and Recovery 432
Business Continuity 432
Disaster Recovery 433
MTBF and MTTR 433
Backups 435
RTO and RPO 437
Remember this… 438
Self-check 439
Summary 439
Key Terms 441
Review Questions 442
Hands-On Project 12 443
Reflection Discussion 12 446
Solutions to Self-Check Questions 447
Appendix A
CompTIA Cloud Essentials+ CLO-002 Certification Exam Objectives 449
Domain 1.0 Cloud Concepts—24%
of Exam 450
Domain 2.0 Business Principles of
Cloud Environments—28% of Exam 451
Domain 3.0 Management and
Technical Operations—26% of Exam 453
Domain 4.0 Governance, Risk,
Compliance, and Security for the
Cloud—22% of Exam 454
Glossary 457
Index 478