Introduction xlii
Chapter 1 Communications in a Connected World 1
Objectives 1
Key Terms 1
Introduction (1.0) 2
Network Types (1.1) 2
Everything Is Online (1.1.2) 2
Who Owns “The Internet”? (1.1.3) 2
Local Networks (1.1.4) 3
Small Home Networks 4
Small Office and Home Office Networks 4
Medium to Large Networks 4
Worldwide Networks 6
Mobile Devices (1.1.5) 6
Smartphone 6
Tablet 7
Smartwatch 8
Smart Glasses 8
Connected Home Devices (1.1.6) 8
Security System 8
Appliances 9
Smart TV 10
Gaming Console 11
Other Connected Devices (1.1.7) 11
Smart Cars 11
RFID Tags 12
Sensors and Actuators 13
Medical Devices 13
Data Transmission (1.2) 14
The Bit (1.2.2) 14
Common Methods of Data Transmission (1.2.3) 15
Bandwidth and Throughput (1.3) 17
Bandwidth (1.3.1) 17
Throughput (1.3.2) 18
Communications in a Connected World Summary (1.4) 18
What Did I Learn in This Chapter? (1.4.1) 19
Reflection Questions (1.4.2) 20
Practice 21
Check Your Understanding Questions 21
Chapter 2 Network Components, Types, and Connections 25
Objectives 25
Key Terms 25
Introduction (2.0) 26
Clients and Servers (2.1) 26
Client and Server Roles (2.1.2) 26
Peer-to-Peer Networks (2.1.3) 27
Peer-to-Peer Applications (2.1.4) 28
Multiple Roles in the Network (2.1.5) 29
Network Components (2.2) 30
Network Infrastructure (2.2.2) 30
End Devices (2.2.3) 32
ISP Connectivity Options (2.3) 33
ISP Services (2.3.1) 33
ISP Connections (2.3.2) 34
Cable and DSL Connections (2.3.3) 35
Additional Connectivity Options (2.3.4) 36
Network Components, Types, and Connections Summary (2.4) 37
What Did I Learn in This Chapter? (2.4.1) 37
Reflection Questions (2.4.2) 38
Practice 39
Check Your Understanding Questions 39
Chapter 3 Wireless and Mobile Networks 41
Objectives 41
Key Terms 41
Introduction (3.0) 42
Wireless Networks (3.1) 42
Other Wireless Networks (3.1.3) 43
Global Positioning System 43
Wi-Fi 43
Bluetooth 43
NFC 43
Mobile Device Connectivity (3.2) 44
Mobile Devices and Wi-Fi (3.2.1) 44
Wi-Fi Settings (3.2.2) 44
Configure Mobile Wi-Fi Connectivity (3.2.3) 46
Configure Cellular Data Settings (3.2.4) 47
Android Cellular Data 47
iOS Cellular Data 48
Simple Connectivity with Bluetooth (3.2.6) 49
Bluetooth Pairing (3.2.7) 50
Explore Your Network Settings on Your Mobile Device (3.2.8) 51
Wireless and Mobile Networks Summary (3.3) 52
What Did I Learn in This Chapter? (3.3.1) 52
Reflection Questions (3.3.2) 53
Practice 54
Check Your Understanding Questions 54
Chapter 4 Build a Home Network 57
Objectives 57
Key Terms 57
Introduction (4.0) 58
Home Network Basics (4.1) 58
Components of a Home Network (4.1.2) 58
Typical Home Network Routers (4.1.3) 59
Network Technologies in the Home (4.2) 60
LAN Wireless Frequencies (4.2.1) 61
Wired Network Technologies (4.2.2) 62
Category 5e Cable 62
Coaxial Cable 62
Fiber-Optic Cable 63
Wireless Standards (4.3) 63
Wi-Fi Networks (4.3.1) 64
Wireless Settings (4.3.2) 64
Network Mode 65
Set Up a Home Router (4.4) 66
First Time Setup (4.4.1) 66
Design Considerations (4.4.2) 67
Build a Home Network Summary (4.5) 69
What Did I Learn in This Chapter? (4.5.1) 69
Reflection Questions (4.5.2) 71
Practice 72
Packet Tracer Activities 72
Check Your Understanding Questions 72
Chapter 5 Communication Principles 75
Objectives 75
Key Terms 75
Introduction (5.0) 76
Networking Protocols (5.1) 76
Communication Protocols (5.1.1) 76
Why Protocols Matter (5.1.2) 78
Communication Standards (5.2) 80
The Internet and Standards (5.2.2) 80
Network Standards Organizations (5.2.3) 80
Network Communication Models (5.3) 81
The TCP/IP Model (5.3.3) 81
The OSI Reference Model (5.3.4) 82
OSI Model and TCP/IP Model Comparison (5.3.5) 83
Communication Principles Summary (5.4) 85
What Did I Learn in This Chapter? (5.4.1) 85
Reflection Questions (5.4.2) 87
Practice 88
Check Your Understanding Questions 88
Chapter 6 Network Media 91
Objectives 91
Key Terms 91
Introduction (6.0) 92
Network Media Types (6.1) 92
Three Media Types (6.1.2) 92
Common Network Cables (6.1.3) 93
Twisted-Pair Cable 93
Coaxial Cable 94
Fiber-Optic Cable 95
Network Media Summary (6.2) 95
What Did I Learn in This Chapter? (6.2.1) 95
Reflection Questions (6.2.2) 96
Practice 97
Check Your Understanding Questions 97
Chapter 7 The Access Layer 101
Objectives 101
Key Terms 101
Introduction (7.0) 102
Encapsulation and the Ethernet Frame (7.1) 102
Encapsulation (7.1.2) 102
The Access Layer (7.2) 104
Ethernet Frame (7.2.1) 104
Access Layer Devices (7.2.2) 105
Ethernet Hubs (7.2.3) 106
Ethernet Switches (7.2.4) 107
The MAC Address Table (7.2.5) 109
The Access Layer Summary (7.3) 111
What Did I Learn in This Chapter? (7.3.1) 111
Reflection Questions (7.3.2) 113
Practice 114
Check Your Understanding Questions 114
Chapter 8 The Internet Protocol 117
Objectives 117
Introduction (8.0) 118
Purpose of an IPv4 Address (8.1) 118
The IPv4 Address (8.1.1) 118
Octets and Dotted-Decimal Notation (8.1.2) 119
The IPv4 Address Structure (8.2) 119
Networks and Hosts (8.2.2) 119
Summary (8.3) 121
What Did I Learn in This Chapter? (8.3.1) 121
Reflection Questions (8.3.2) 121
Practice 122
Packet Tracer Activities 122
Check Your Understanding Questions 122
Chapter 9 IPv4 and Network Segmentation 125
Objectives 125
Key Terms 125
Introduction (9.0) 126
IPv4 Unicast, Broadcast, and Multicast (9.1) 126
Unicast (9.1.2) 126
Broadcast (9.1.4) 127
Multicast (9.1.6) 129
Types of IPv4 Addresses (9.2) 130
Public and Private IPv4 Addresses (9.2.1) 130
Routing to the Internet (9.2.2) 131
Special-Use IPv4 Addresses (9.2.4) 132
Loopback Addresses 132
Link-Local addresses 133
Legacy Classful Addressing (9.2.5) 133
Assignment of IP Addresses (9.2.6) 134
Network Segmentation (9.3) 135
Broadcast Domains and Segmentation (9.3.2) 136
Problems with Large Broadcast Domains (9.3.3) 137
Reasons for Segmenting Networks (9.3.4) 138
IPv4 and Network Segmentation Summary (9.4) 140
What Did I Learn in This Chapter? (9.4.1) 140
Reflection Questions (9.4.2) 143
Practice 144
Check Your Understanding Questions 144
Chapter 10 IPv6 Addressing Formats and Rules 147
Objectives 147
Key Terms 147
Introduction (10.0) 148
IPv4 Issues (10.1) 148
The Need for IPv6 (10.1.1) 148
Internet of Things 149
IPv4 and IPv6 Coexistence (10.1.2) 150
Dual Stack 150
Tunneling 150
Translation 151
IPv6 Addressing (10.2) 152
Hexadecimal Number System (10.2.1) 152
IPv6 Addressing Formats (10.2.2) 152
Preferred Format 153
Rule 1—Omit Leading Zeros (10.2.4) 153
Rule 2—Double Colon (10.2.5) 155
IPv6 Addressing Formats and Rules Summary (10.3) 156
What Did I Learn in This Chapter? (10.3.1) 157
Reflection Questions (10.3.2) 158
Practice 159
Check Your Understanding Questions 159
Chapter 11 Dynamic Addressing with DHCP 163
Objectives 163
Key Term 163
Introduction (11.0) 164
Static and Dynamic Addressing (11.1) 164
Static IPv4 Address Assignment (11.1.1) 164
Dynamic IPv4 Address Assignment (11.1.2) 165
DHCP Servers (11.1.3) 166
DHCPv4 Configuration (11.2) 167
DHCPv4 Operation (11.2.1) 168
DHCP Service Configuration (11.2.3) 169
Dynamic Addressing with DHCP Summary (11.3) 170
What Did I Learn in This Chapter? (11.3.1) 170
Reflection Questions (11.3.2) 171
Practice 172
Packet Tracer Activities 172
Check Your Understanding Questions 172
Chapter 12 Gateways to Other Networks 175
Objectives 175
Key Term 175
Introduction (12.0) 176
Network Boundaries (12.1) 176
Routers as Gateways (12.1.2) 176
Routers as Boundaries Between Networks (12.1.3) 177
Network Address Translation (12.2) 178
NAT Operation (12.2.1) 179
Gateways to Other Networks Summary (12.3) 180
What Did I Learn in This Chapter? (12.3.1) 180
Reflection Questions (12.3.2) 181
Practice 182
Packet Tracer Activities 182
Check Your Understanding Questions 182
Chapter 13 The ARP Process 185
Objectives 185
Key Term 185
Introduction (13.0) 186
MAC and IP (13.1) 186
Destination on Same Network (13.1.1) 186
Destination on Remote Network (13.1.2) 187
Broadcast Containment (13.2) 189
Broadcast Domains (13.2.2) 190
Access Layer Communication (13.2.3) 191
ARP (13.2.5) 192
The ARP Process Summary (13.3) 193
What Did I Learn in This Chapter? (13.3.1) 193
Reflection Questions (13.3.2) 194
Practice 195
Packet Tracer Activities 195
Check Your Understanding Questions 195
Chapter 14 Routing Between Networks 199
Objectives 199
Key Terms 199
Introduction (14.0) 200
The Need for Routing (14.1) 200
Now We Need Routing (14.1.2) 200
The Routing Table (14.2) 201
Routing Table Entries (14.2.4) 202
The Default Gateway (14.2.5) 203
Create a LAN (14.3) 204
Local Area Networks (14.3.1) 205
Local and Remote Network Segments (14.3.2) 205
All Hosts in One Local Segment 206
Hosts on a Remote Segment 206
Routing Between Networks Summary (14.4) 208
What Did I Learn in This Chapter? (14.4.1) 208
Reflection Questions (14.4.2) 210
Practice 211
Packet Tracer Activities 211
Check Your Understanding Questions 211
Chapter 15 TCP and UDP 215
Objectives 215
Key Terms 215
Introduction (15.0) 216
TCP and UDP (15.1) 216
Protocol Operations (15.1.1) 216
TCP and UDP (15.1.2) 217
TCP Reliability (15.1.3) 218
UDP Best Effort Delivery (15.1.4) 218
Port Numbers (15.2) 219
TCP and UDP Port Numbers (15.2.1) 219
Socket Pairs (15.2.2) 222
The netstat Command (15.2.3) 223
TCP and UDP Summary (15.3) 224
What Did I Learn in This Chapter? (15.3.1) 224
Reflection Questions (15.3.2) 225
Practice 226
Check Your Understanding Questions 226
Chapter 16 Application Layer Services 229
Objectives 229
Key Terms 229
Introduction (16.0) 230
The Client-Server Relationship (16.1) 230
Client and Server Interaction (16.1.1) 230
Client Requests a Web Page (16.1.2) 231
URI, URN, and URL (16.1.3) 232
Network Application Services (16.2) 233
Common Network Application Services (16.2.1) 233
Domain Name System (16.3) 234
Domain Name Translation (16.3.1) 234
DNS Servers (16.3.2) 235
A Note About Syntax Checker Activities (16.3.3) 236
Web Clients and Servers (16.4) 236
HTTP and HTML (16.4.2) 237
FTP Clients and Servers (16.5) 238
File Transfer Protocol (16.5.1) 238
Virtual Terminals (16.6) 239
Telnet (16.6.2) 240
Security Issues with Telnet (16.6.3) 241
Email and Messaging (16.7) 242
Email Clients and Servers (16.7.1) 242
Email Protocols (16.7.2) 242
Simple Mail Transfer Protocol (SMTP) 243
Post Office Protocol (POP3) 243
Internet Message Access Protocol (IMAP4) 243
Text Messaging (16.7.3) 244
Internet Phone Calls (16.7.4) 245
Application Layer Services Summary (16.8) 245
What Did I Learn in This Chapter? (16.8.1) 245
Reflection Questions (16.8.2) 248
Practice 249
Packet Tracer Activities 249
Check Your Understanding Questions 249
Chapter 17 Network Testing Utilities 253
Objectives 253
Key Terms 253
Introduction (17.0) 254
Troubleshooting Commands (17.1) 254
Overview of Troubleshooting Commands (17.1.1) 254
The ipconfig Command (17.1.2) 254
The ping Command (17.1.4) 258
Ping Results (17.1.5) 259
Network Testing Utilities Summary (17.2) 260
What Did I Learn in This Chapter? (17.2.1) 260
Reflection Questions (17.2.2) 261
Practice 262
Packet Tracer Activities 262
Check Your Understanding Questions 262
Chapter 18 Network Design 265
Objectives 265
Key Terms 265
Introduction (18.0) 266
Reliable Networks (18.1) 266
Network Architecture (18.1.1) 266
Fault Tolerance (18.1.3) 267
Scalability (18.1.4) 267
Quality of Service (18.1.5) 269
Network Security (18.1.6) 270
Hierarchical Network Design (18.2) 271
Physical and Logical Addresses (18.2.1) 271
Hierarchical Analogy (18.2.4) 272
Access, Distribution, and Core (18.2.6) 273
Access Layer 273
Distribution Layer 274
Core Layer 274
Network Design Summary (18.3) 275
What Did I Learn in This Chapter? (18.3.1) 275
Reflection Questions (18.3.2) 276
Practice 277
Labs 277
Check Your Understanding Questions 277
Chapter 19 Cloud and Virtualization 281
Objectives 281
Key Terms 281
Introduction (19.0) 282
Cloud and Cloud Services (19.1) 282
Types of Clouds (19.1.2) 282
Cloud Services (19.1.3) 283
Cloud Computing and Virtualization (19.1.4) 284
Virtualization (19.2) 285
Advantages of Virtualization (19.2.1) 285
Hypervisors (19.2.2) 286
Type 1 Hypervisor—“Bare Metal” Approach 286
Type 2 Hypervisor—“Hosted” Approach 286
Cloud and Virtualization Summary (19.3) 287
What Did I Learn in This Chapter? (19.3.1) 287
Reflection Questions (19.3.2) 289
Practice 290
Labs 290
Check Your Understanding Questions 290
Chapter 20 Number Systems 293
Objectives 293
Key Terms 293
Introduction (20.0) 294
Binary Number System (20.1) 294
Binary and IPv4 Addresses (20.1.1) 294
Decimal to Binary Conversion (20.1.5) 296
Decimal to Binary Conversion Example (20.1.6) 300
IPv4 Addresses (20.1.9) 307
Hexadecimal Number System (20.2) 308
Hexadecimal and IPv6 Addresses (20.2.1) 308
Number Systems Summary (20.3) 311
What Did I Learn in This Chapter? (20.3.1) 311
Reflection Questions (20.3.2) 311
Practice 312
Check Your Understanding Questions 312
Chapter 21 Ethernet Switching 315
Objectives 315
Key Terms 315
Introduction (21.0) 316
Ethernet (21.1) 316
The Rise of Ethernet (21.1.1) 316
Ethernet Evolution (21.1.2) 317
Ethernet Frames (21.2) 318
Ethernet Encapsulation (21.2.1) 318
Data Link Sublayers (21.2.2) 319
MAC Sublayer (21.2.3) 320
Data Encapsulation 321
Accessing the Media 321
Ethernet Frame Fields (21.2.4) 322
Ethernet MAC Address (21.3) 324
MAC Address and Hexadecimal (21.3.1) 324
Unicast MAC Address (21.3.2) 326
Broadcast MAC Address (21.3.3) 327
Multicast MAC Address (21.3.4) 328
The MAC Address Table (21.4) 330
Switch Fundamentals (21.4.1) 330
Switch Learning and Forwarding (21.4.2) 331
Examine the Source MAC Address 331
Find the Destination MAC Address 332
Filtering Frames (21.4.3) 333
Ethernet Switching Summary (21.5) 336
What Did I Learn in This Chapter? (21.5.1) 336
Reflection Questions (21.5.2) 338
Practice 339
Labs 339
Check Your Understanding Questions 339
Chapter 22 Network Layer 343
Objectives 343
Key Terms 343
Introduction (22.0) 344
Network Layer Characteristics (22.1) 344
The Network Layer (22.1.2) 344
IP Encapsulation (22.1.3) 346
Characteristics of IP (22.1.4) 347
Connectionless (22.1.5) 347
Best Effort (22.1.6) 348
Media Independent (22.1.7) 349
IPv4 Packet (22.2) 350
IPv4 Packet Header (22.2.1) 350
IPv4 Packet Header Fields (22.2.2) 350
IPv6 Packet (22.3) 352
Limitations of IPv4 (22.3.1) 352
IPv6 Overview (22.3.2) 353
IPv4 Packet Header Fields in the IPv6 Packet Header (22.3.3) 354
IPv6 Packet Header (22.3.4) 356
Network Layer Summary (22.4) 357
What Did I Learn in This Chapter? (22.4.1) 357
Reflection Questions (22.4.2) 358
Practice 359
Check Your Understanding Questions 359
Chapter 23 IPv4 Address Structure 363
Objectives 363
Key Terms 363
Introduction (23.0) 364
IPv4 Address Structure (23.1) 364
Network and Host Portions (23.1.1) 364
The Subnet Mask (23.1.2) 365
The Prefix Length (23.1.3) 366
Determining the Network: Logical AND (23.1.4) 367
IPv4 Address Structure Summary (23.2) 369
What Did I Learn in This Chapter? (23.2.1) 369
Reflection Questions (23.2.2) 370
Practice 371
Check Your Understanding Questions 371
Chapter 24 Address Resolution 375
Objectives 375
Key Terms 375
Introduction (24.0) 376
ARP (24.1) 376
ARP Overview (24.1.1) 376
ARP Functions (24.1.2) 377
Removing Entries from an ARP Table (24.1.6) 380
ARP Tables on Devices (24.1.7) 381
ARP Issues—ARP Broadcasts and ARP Spoofing (24.1.8) 382
Address Resolution Summary (24.2) 384
What Did I Learn in This Chapter? (24.2.1) 384
Reflection Questions (24.2.2) 385
Practice 386
Labs 386
Packet Tracer Activities 386
Check Your Understanding Questions 386
Chapter 25 IP Addressing Services 391
Objectives 391
Key Terms 391
Introduction (25.0) 392
DNS Services (25.1) 392
Domain Name System (25.1.2) 392
DNS Message Format (25.1.3) 395
DNS Hierarchy (25.1.4) 395
The nslookup Command (25.1.5) 397
DHCP Services (25.2) 398
Dynamic Host Configuration Protocol (25.2.1) 398
DHCP Messages (25.2.3) 399
IP Addressing Services Summary (25.3) 401
What Did I Learn in This Chapter? (25.3.1) 401
Reflection Questions (25.3.2) 402
Practice 403
Labs 403
Check Your Understanding Questions 403
Chapter 26 Transport Layer 407
Objectives 407
Key Terms 407
Introduction (26.0) 408
Transportation of Data (26.1) 408
Role of the Transport Layer (26.1.1) 408
Transport Layer Responsibilities (26.1.2) 409
Transport Layer Protocols (26.1.3) 413
Transmission Control Protocol (TCP) (26.1.4) 413
User Datagram Protocol (UDP) (26.1.5) 414
The Right Transport Layer Protocol for the Right Application (26.1.6) 415
TCP Overview (26.2) 417
TCP Features (26.2.1) 417
TCP Header (26.2.2) 418
TCP Header Fields (26.2.3) 418
Applications That Use TCP (26.2.4) 419
UDP Overview (26.3) 420
UDP Features (26.3.1) 420
UDP Header (26.3.2) 420
UDP Header Fields (26.3.3) 421
Applications That Use UDP (26.3.4) 421
Port Numbers (26.4) 422
Multiple Separate Communications (26.4.1) 422
Socket Pairs (26.4.2) 423
Port Number Groups (26.4.3) 424
The netstat Command (26.4.4) 426
TCP Communication Process (26.5) 427
TCP Server Processes (26.5.1) 427
TCP Connection Establishment (26.5.2) 430
Session Termination (26.5.3) 431
TCP Three-Way Handshake Analysis (26.5.4) 432
Reliability and Flow Control (26.6) 433
TCP Reliability—Guaranteed and Ordered Delivery (26.6.1) 433
TCP Reliability—Data Loss and Retransmission (26.6.3) 435
TCP Flow Control—Window Size and Acknowledgments (26.6.5) 437
TCP Flow Control—Maximum Segment Size (MSS) (26.6.6) 439
TCP Flow Control—Congestion Avoidance (26.6.7) 440
UDP Communication (26.7) 441
UDP Low Overhead Versus Reliability (26.7.1) 441
UDP Datagram Reassembly (26.7.2) 441
UDP Server Processes and Requests (26.7.3) 443
UDP Client Processes (26.7.4) 443
Transport Layer Summary (26.8) 447
What Did I Learn in This Chapter? (26.8.2) 447
Reflection Questions (26.8.3) 449
Practice 450
Packet Tracer Activities 450
Check Your Understanding Questions 450
Chapter 27 The Cisco IOS Command Line 455
Objectives 455
Key Terms 455
Introduction (27.0) 456
Navigate the IOS (27.1) 456
The Cisco IOS Command-Line Interface (27.1.1) 456
Primary Command Modes (27.1.2) 457
A Note About Syntax Checker Activities (27.1.5) 458
The Command Structure (27.2) 458
Basic IOS Command Structure (27.2.1) 458
IOS Command Syntax (27.2.2) 459
Hotkeys and Shortcuts (27.2.4) 460
View Device Information (27.3) 462
show Commands (27.3.2) 463
The Cisco IOS Command Line Summary (27.4) 469
What Did I Learn in This Chapter? (27.4.1) 469
Reflection Questions (27.4.2) 471
Practice 472
Packet Tracer Activities 472
Check Your Understanding Questions 472
Chapter 28 Build a Small Cisco Network 475
Objectives 475
Key Term 475
Introduction (28.0) 476
Basic Switch Configuration (28.1) 476
Basic Switch Configuration Steps (28.1.1) 476
Switch Virtual Interface Configuration (28.1.2) 478
Configure Initial Router Settings (28.2) 479
Basic Router Configuration Steps (28.2.1) 479
Basic Router Configuration Example (28.2.2) 480
Secure the Devices (28.3) 482
Password Recommendations (28.3.1) 482
Secure Remote Access (28.3.2) 483
Enable SSH (28.3.3) 485
Verify SSH (28.3.5) 487
Connecting the Switch to the Router (28.4) 488
Default Gateway for a Host (28.4.1) 488
Default Gateway on a Switch (28.4.2) 490
Build a Small Cisco Network Summary (28.5) 492
What Did I Learn in This Chapter? (28.5.1) 492
Reflection Questions (28.5.2) 495
Practice 496
Packet Tracer Activities 496
Check Your Understanding Questions 496
Chapter 29 ICMP 499
Objectives 499
Introduction (29.0) 500
ICMP Messages (29.1) 500
ICMPv4 and ICMPv6 Messages (29.1.1) 500
Host Reachability (29.1.2) 500
Destination or Service Unreachable (29.1.3) 501
Time Exceeded (29.1.4) 502
ICMPv6 Messages (29.1.5) 502
Ping and Traceroute Tests (29.2) 505
Ping—Test Connectivity (29.2.1) 505
Ping the Local Loopback (29.2.2) 506
Ping the Default Gateway (29.2.3) 507
Ping a Remote Host (29.2.4) 508
Traceroute—Test the Path (29.2.5) 509
Round-Trip Time (RTT) 509
IPv4 TTL and IPv6 Hop Limit 509
ICMP Summary (29.3) 511
What Did I Learn in This Chapter? (29.3.2) 511
Reflection Questions (29.3.3) 513
Practice 514
Packet Tracer Activities 514
Check Your Understanding Questions 514
Chapter 30 Physical Layer 519
Objectives 519
Key Terms 519
Introduction (30.0) 520
Purpose of the Physical Layer (30.1) 520
The Physical Connection (30.1.1) 520
The Physical Layer Process (30.1.2) 522
Physical Layer Characteristics (30.2) 523
Physical Layer Standards (30.2.1) 523
Physical Components (30.2.2) 525
Encoding (30.2.3) 525
Signaling (30.2.4) 525
Bandwidth (30.2.6) 527
Bandwidth Terminology (30.2.7) 528
Latency 528
Throughput 529
Goodput 529
Copper Cabling (30.3) 529
Characteristics of Copper Cabling (30.3.1) 529
Types of Copper Cabling (30.3.2) 531
Unshielded Twisted-Pair (UTP) (30.3.3) 531
Shielded Twisted-Pair (STP) (30.3.4) 533
Coaxial Cable (30.3.5) 533
UTP Cabling (30.4) 535
Properties of UTP Cabling (30.4.1) 535
UTP Cabling Standards and Connectors (30.4.2) 536
Straight-Through and Crossover UTP Cables (30.4.3) 539
Fiber-Optic Cabling (30.5) 541
Properties of Fiber-Optic Cabling (30.5.1) 541
Types of Fiber Media (30.5.2) 541
Single-Mode Fiber 541
Multimode Fiber 542
Fiber-Optic Cabling Usage (30.5.3) 543
Fiber-Optic Connectors (30.5.4) 543
Fiber Patch Cords (30.5.5) 545
Fiber Versus Copper (30.5.6) 547
Summary (30.6) 548
What Did I Learn in This Chapter? (30.6.1) 548
Reflection Questions (30.6.2) 550
Practice 551
Check Your Understanding Questions 551
Chapter 31 Data Link Layer 555
Objectives 555
Key Terms 555
Introduction (31.0) 556
Topologies (31.1) 556
Physical and Logical Topologies (31.1.1) 556
WAN Topologies (31.1.2) 558
Point-to-Point 558
Hub and Spoke 558
Mesh 559
Point-to-Point WAN Topology (31.1.4) 559
LAN Topologies (31.1.5) 560
Legacy LAN Topologies 560
Media Access Control Methods (31.2) 561
Half- and Full-Duplex Communication (31.2.1) 562
Half-Duplex Communication 562
Full-Duplex Communication 562
Access Control Methods (31.2.2) 563
Contention-Based Access 563
Controlled Access 564
Contention-Based Access—CSMA/CD (31.2.3) 564
Contention-Based Access—CSMA/CA (31.2.4) 566
Summary (31.3) 568
What Did I Learn in This Chapter? (31.3.1) 568
Reflection Questions (31.3.2) 568
Practice 569
Check Your Understanding Questions 569
Chapter 32 Routing at the Network Layer 571
Objectives 571
Key Terms 571
Introduction (32.0) 572
How a Host Routes (32.1) 572
Host Forwarding Decision (32.1.1) 572
Default Gateway (32.1.2) 574
A Host Routes to the Default Gateway (32.1.3) 574
Host Routing Tables (32.1.4) 575
Routing Tables (32.2) 576
Router Packet Forwarding Decision (32.2.1) 576
IP Router Routing Table (32.2.2) 577
Static Routing (32.2.3) 579
Dynamic Routing (32.2.4) 580
Introduction to an IPv4 Routing Table (32.2.6) 582
Summary (32.3) 582
What Did I Learn in This Chapter? (32.3.1) 582
Reflection Questions (32.3.2) 583
Practice 584
Check Your Understanding Questions 584
Chapter 33 IPv6 Addressing 587
Objectives 587
Key Terms 587
Introduction (33.0) 588
IPv6 Address Types (33.1) 588
Unicast, Multicast, Anycast (33.1.1) 588
IPv6 Prefix Length (33.1.2) 588
Types of IPv6 Unicast Addresses (33.1.3) 589
A Note About the Unique Local Address (33.1.4) 590
IPv6 GUA (33.1.5) 591
IPv6 GUA Structure (33.1.6) 592
Global Routing Prefix 592
Subnet ID 592
Interface ID 593
IPv6 LLA (33.1.7) 593
GUA and LLA Static Configuration (33.2) 595
Static GUA Configuration on a Router (33.2.1) 595
Static GUA Configuration on a Windows Host (33.2.2) 596
Static Configuration of a Link-Local Unicast Address (33.2.3) 598
Dynamic Addressing for IPv6 GUAs (33.3) 599
RS and RA Messages (33.3.1) 599
Method 1: SLAAC (33.3.2) 601
Method 2: SLAAC and Stateless DHCPv6 (33.3.3) 602
Method 3: Stateful DHCPv6 (33.3.4) 603
EUI-64 Process vs. Randomly Generated (33.3.5) 604
EUI-64 Process (33.3.6) 605
Randomly Generated Interface IDs (33.3.7) 606
Dynamic Addressing for IPv6 LLAs (33.4) 607
Dynamic LLAs (33.4.1) 607
Dynamic LLAs on Windows (33.4.2) 608
Dynamic LLAs on Cisco Routers (33.4.3) 609
Verify IPv6 Address Configuration (33.4.4) 609
IPv6 Multicast Addresses (33.5) 612
Assigned IPv6 Multicast Addresses (33.5.1) 612
Well-Known IPv6 Multicast Addresses (33.5.2) 613
Solicited-Node IPv6 Multicast Addresses (33.5.3) 614
Summary (33.6) 615
What Did I Learn in This Chapter? (33.6.1) 615
Reflection Questions (33.6.2) 616
Practice 617
Packet Tracer Activities 617
Check Your Understanding Questions 617
Chapter 34 IPv6 Neighbor Discovery 621
Objectives 621
Key Terms 621
Introduction (34.0) 622
Neighbor Discovery Operation (34.1) 622
IPv6 Neighbor Discovery Messages (34.1.2) 622
IPv6 Neighbor Discovery—Address Resolution (34.1.3) 623
Summary (34.2) 625
What Did I Learn in This Chapter? (34.2.1) 625
Practice 626
Packet Tracer Activities 626
Check Your Understanding Questions 626
Chapter 35 Cisco Switches and Routers 629
Objectives 629
Key Terms 629
Introduction (35.0) 630
Cisco Switches (35.1) 630
Connect More Devices (35.1.1) 630
Cisco LAN Switches (35.1.2) 631
Type of Ports 632
Speed Required 632
Expandability 633
Manageability 633
LAN Switch Components (35.1.5) 634
Switch Speeds and Forwarding Methods (35.2) 635
Frame Forwarding Methods on Cisco Switches (35.2.1) 635
Cut-Through Switching (35.2.2) 636
Memory Buffering on Switches (35.2.3) 638
Duplex and Speed Settings (35.2.4) 638
Auto-MDIX (35.2.5) 640
Switch Boot Process (35.3) 641
Power Up the Switch (35.3.1) 642
In-Band and Out-of-Band Management (35.3.3) 644
Out-of-Band Management 644
In-Band Management 644
IOS Startup Files (35.3.4) 645
Cisco Routers (35.4) 646
Router Components (35.4.2) 646
Router Interface Ports (35.4.3) 647
Router Boot Process (35.5) 648
Power Up the Router (35.5.1) 648
Management Ports (35.5.2) 651
Summary (35.6) 653
What Did I Learn in This Chapter? (35.6.1) 653
Reflection Questions (35.6.2) 654
Practice 655
Check Your Understanding Questions 655
Chapter 36 Troubleshoot Common Network Problems 659
Objectives 659
Introduction (36.0) 660
The Troubleshooting Process (36.1) 660
Network Troubleshooting Overview (36.1.2) 660
Gather Information (36.1.3) 660
Structured Troubleshooting Methods (36.1.4) 662
Bottom-Up 662
Top-Down 663
Divide-and-Conquer 664
Follow-the-Path 664
Substitution 665
Comparison 665
Educated Guess 665
Guidelines for Selecting a Troubleshooting Method (36.1.5) 665
Physical Layer Problems (36.2) 667
Common Layer 1 Problems (36.2.1) 667
The Sense of Sight 667
The Senses of Smell and Taste 668
The Sense of Touch 668
The Sense of Hearing 668
Wireless Router LEDs (36.2.2) 668
Cabling Problems (36.2.3) 670
Troubleshoot Wireless Issues (36.3) 671
Causes of Wireless Issues (36.3.1) 671
Authentication and Association Errors (36.3.2) 672
Common Internet Connectivity Issues (36.4) 674
DHCP Server Configuration Errors (36.4.1) 674
Check Internet Configuration (36.4.2) 674
Check Firewall Settings (36.4.3) 677
Divide and Conquer with ping (36.4.5) 678
The tracert Command (36.4.6) 678
The netstat Command (36.4.7) 680
The nslookup Command (36.4.8) 682
Customer Support (36.5) 683
Sources of Help (36.5.1) 683
When to Call for Help (36.5.2) 684
Support Desk Interaction (36.5.3) 685
Issue Resolution (36.5.4) 686
Support Desk Tickets and Work Orders (36.5.5) 686
Troubleshoot Common Network Problems Summary (36.6) 688
What Did I Learn in This Chapter? (36.6.1) 688
Practice 692
Packet Tracer Activities 692
Check Your Understanding Questions 692
Chapter 37 Network Support 697
Objectives 697
Key Terms 697
Introduction (37.0) 698
Diagnostics and Troubleshooting Methodologies (37.1) 698
Troubleshooting Process Review (37.1.1) 698
Seven-Step Troubleshooting Process (37.1.2) 699
Define the Problem 699
Gather Information 700
Analyze Information 700
Eliminate Possible Causes 700
Propose Hypothesis 700
Test Hypothesis 700
Solve the Problem 700
Troubleshooting with Layered Models (37.1.3) 701
Structured Troubleshooting Methods (37.1.4) 701
Guidelines for Selecting a Troubleshooting Method (37.1.5) 702
Document Findings, Actions, and Outcomes (37.1.6) 703
Network Documentation (37.2) 704
Documentation Overview (37.2.1) 704
Network Topologies and Descriptions (37.2.2) 704
PAN 704
LAN 705
VLAN 706
WLAN 706
WMN 707
CAN 708
MAN 708
WAN 709
VPN 710
Enterprise Network Topologies (37.2.4) 710
Network Cloud Services and Applications (37.2.5) 713
SaaS (Software as a Service) 713
PaaS (Platform as a Service) 713
IaaS (Infrastructure as a Service) 714
XaaS (Anything/Everything as a Service) 714
Wireless Standards (37.2.6) 714
Licensed and Unlicensed Bands 716
Network Device Documentation (37.2.8) 717
Router Device Documentation 717
LAN Switch Device Documentation 717
End-System Documentation 718
Establish a Network Baseline (37.2.9) 718
Cisco Discovery Protocol (CDP) Overview (37.2.10) 719
Discover Devices Using CDP (37.2.11) 720
Help Desks (37.3) 723
The Security Policy (37.3.1) 723
Help Desks (37.3.2) 725
Ticketing Systems (37.3.3) 727
Question End Users (37.3.4) 729
Active Listening (37.3.6) 731
Gather Information for Host-Related Tickets (37.3.8) 733
Beep Codes 733
BIOS Information 733
Event Viewer 733
Device Manager 734
Task Manager 735
Diagnostic Tools 736
Gather Information for Cisco Device-Related Tickets (37.3.9) 736
Analyze the Information (37.3.10) 737
Troubleshoot Endpoint Connectivity (37.4) 738
Windows Network Setup (37.4.1) 738
Verify Connectivity in Windows (37.4.2) 740
Linux Network Setup (37.4.3) 741
Verify Connectivity in Linux (37.4.4) 742
macOS Network Setup (37.4.5) 743
Verify Connectivity in macOS (37.4.6) 744
Set Up and Verify Networking in iOS (37.4.7) 746
Set Up and Verify Networking in Android (37.4.8) 747
Troubleshoot a Network (37.5) 750
Network Devices as Sources of Network Information (37.5.1) 750
Packet Capture and Protocol Analysis (37.5.2) 752
Measuring Network Throughput (37.5.5) 754
Troubleshoot Connectivity Remotely (37.6) 755
Supporting Remote Users (37.6.1) 756
Remote Access with Telnet, SSH, and RDP (37.6.2) 757
Understanding VPNs (37.6.4) 760
Site-to-Site VPN 760
Remote-Access VPN 761
Network Management Systems (37.6.5) 763
Network Support Summary (37.7) 765
What Did I Learn in This Chapter? (37.7.1) 765
Reflection Questions (37.7.2) 769
Practice 770
Labs 770
Packet Tracer Activities 770
Check Your Understanding Questions 770
Chapter 38 Cybersecurity Threats, Vulnerabilities, and Attacks 775
Objectives 775
Key Terms 775
Introduction (38.0) 776
Common Threats (38.1) 776
Threat Domains (38.1.1) 776
Types of Cyber Threats (38.1.2) 777
Internal vs. External Threats (38.1.3) 777
User Threats and Vulnerabilities (38.1.5) 778
Threats to Devices (38.1.6) 780
Threats to the Local Area Network (38.1.7) 780
Threats to the Private Cloud (38.1.8) 781
Threats to the Public Cloud (38.1.9) 781
Threats to Applications (38.1.10) 781
Threat Complexity (38.1.12) 782
Backdoors and Rootkits (38.1.13) 782
Backdoors 782
Rootkits 783
Threat Intelligence and Research Sources (38.1.14) 783
The Dark Web 783
Indicator of Compromise (IOC) 783
Automated Indicator Sharing (AIS) 783
Deception (38.2) 784
Social Engineering (38.2.1) 784
Pretexting 784
Something for Something (Quid Pro Quo) 784
Identity Fraud 784
Social Engineering Tactics (38.2.2) 785
Shoulder Surfing and Dumpster Diving (38.2.4) 786
Impersonation and Hoaxes (38.2.5) 786
Impersonation 786
Hoaxes 786
Piggybacking and Tailgating (38.2.6) 787
Other Methods of Deception (38.2.7) 787
Defending Against Deception (38.2.9) 788
Cyber Attacks (38.3) 788
Malware (38.3.1) 788
Viruses 789
Worms 789
Trojan Horse 789
Logic Bombs (38.3.2) 789
Ransomware (38.3.3) 790
Denial of Service Attacks (38.3.4) 790
Overwhelming Quantity of Traffic 790
Maliciously Formatted Packets 791
Domain Name System (38.3.5) 791
Domain Reputation 791
DNS Spoofing 791
Domain Hijacking 791
Uniform Resource Locator (URL) Redirection 792
Layer 2 Attacks (38.3.6) 792
Spoofing 792
MAC Flooding 792
Man-in-the-Middle and Man-in-the-Mobile Attacks (38.3.8) 793
Man-in-the-Middle (MitM) 793
Man-in-the-Mobile (MitMo) 793
Zero-Day Attacks (38.3.9) 793
Keyboard Logging (38.3.10) 793
Defending Against Attacks (38.3.12) 794
Wireless and Mobile Device Attacks (38.4) 794
Grayware and SMiShing (38.4.1) 794
Rogue Access Points (38.4.2) 795
Radio Frequency Jamming (38.4.3) 795
Bluejacking and Bluesnarfing (38.4.4) 796
Bluejacking 796
Bluesnarfing 796
Attacks Against Wi-Fi Protocols (38.4.5) 796
Wi-Fi and Mobile Defense (38.4.6) 797
Application Attacks (38.5) 797
Cross-Site Scripting (38.5.1) 797
Code Injection (38.5.2) 798
XML Injection Attack 798
SQL Injection Attack 798
DLL Injection Attack 798
LDAP Injection Attack 798
Buffer Overflow (38.5.3) 799
Remote Code Executions (38.5.4) 799
Other Application Attacks (38.5.5) 799
Defending Against Application Attacks (38.5.7) 801
Spam (38.5.8) 801
Phishing (38.5.9) 802
Phishing 802
Spear Phishing 802
Vishing, Pharming, and Whaling (38.5.10) 802
Vishing 802
Pharming 803
Whaling 803
Defending Against Email and Browser Attacks (38.5.12) 803
Physical Attacks 804
Adversarial Artificial Intelligence Attacks 804
Supply Chain Attacks 804
Cloud-Based Attacks 804
Cybersecurity Threats, Vulnerabilities, and Attacks
Summary (38.6) 805
What Did I Learn in This Chapter? (38.6.1) 805
Reflection Questions (38.6.2) 810
Practice 811
Labs 811
Check Your Understanding Questions 811
Chapter 39 Network Security 813
Objectives 813
Key Terms 813
Introduction (39.0) 814
Security Foundations (39.1) 814
The Cybersecurity Cube (39.1.1) 814
Confidentiality, Integrity, and Availability (39.1.2) 816
CIA Triad—The Principle of Confidentiality (39.1.3) 816
Data Integrity (39.1.5) 817
Ensuring Availability (39.1.7) 819
Access Control (39.2) 820
Physical Access Controls (39.2.1) 820
Logical Access Controls (39.2.2) 821
Administrative Access Controls (39.2.3) 821
Authentication, Authorization, and Accounting (AAA) (39.2.4) 822
Authentication 822
Authorization 822
Accounting 823
What Is Identification? (39.2.5) 823
Federated Identity Management (39.2.6) 823
Authentication Methods (39.2.7) 824
What You Know 824
What You Have 824
Who You Are 825
Passwords (39.2.8) 825
Password Managers 826
Multi-Factor Authentication 827
Multi-Factor Authentication (39.2.9) 827
Authorization (39.2.10) 827
When to Implement Authorization 827
How to Implement Authorization 828
Accounting (39.2.11) 828
Defending Systems and Devices (39.3) 829
Operating System Security (39.3.1) 829
A Good Administrator 829
A Systematic Approach 829
A Baseline 830
Types of Antimalware (39.3.3) 830
Watch Out for Rogue Antivirus Products 830
Fileless Attacks Are Difficult to Detect and Remove 830
Scripts Can also Be Malware 830
Always Remove Unapproved Software 830
Patch Management (39.3.4) 831
What Are Patches? 831
What Do You Need to Do? 831
A Proactive Approach 831
Endpoint Security (39.3.5) 832
Host-Based Firewalls 832
Host Intrusion Detection Systems (HIDSs) 832
Host Intrusion Prevention Systems (HIPSs) 832
Endpoint Detection and Response (EDR) 832
Data Loss Prevention (DLP) 833
Next-Generation Firewall (NGFW) 833
Host Encryption (39.3.6) 833
Boot Integrity (39.3.7) 834
What Is Boot Integrity? 834
How Does Secure Boot Work? 834
What Is Measured Boot? 834
Apple System Security Features (39.3.8) 835
Physical Protection of Devices (39.3.9) 836
Computer Equipment 836
Door Locks 836
Radio Frequency Identification (RFID) Systems 836
Antimalware Protection (39.4) 836
Endpoint Threats (39.4.1) 837
Endpoint Security (39.4.2) 837
Host-Based Malware Protection (39.4.3) 839
Antivirus/Antimalware Software 839
Host-Based Firewall 840
Host-Based Security Suites 840
Network-Based Malware Protection (39.4.4) 841
Firewalls and Host-Based Intrusion Prevention (39.5) 842
Firewalls (39.5.1) 842
Common Firewall Properties 843
Firewall Benefits 843
Firewall Limitations 843
Types of Firewalls (39.5.2) 843
Packet Filtering (Stateless) Firewall 843
Stateful Firewall 844
Application Gateway Firewall 844
Next-Generation Firewall 846
Packet Filtering Firewall Benefits and Limitations (39.5.4) 847
Stateful Firewall Benefits and Limitations (39.5.5) 848
Host-Based Firewalls (39.5.6) 849
Windows Defender Firewall 850
iptables 850
nftables 850
TCP Wrappers 850
Antimalware Programs (39.5.7) 850
Windows Defender Firewall (39.5.8) 851
Secure Wireless Access (39.6) 854
Wireless Security Overview (39.6.2) 854
DoS Attacks (39.6.3) 854
Rogue Access Points (39.6.4) 855
Man-in-the-Middle Attack (39.6.5) 856
SSID Cloaking and MAC Address Filtering (39.6.8) 858
SSID Cloaking 859
MAC Addresses Filtering 859
802.11 Original Authentication Methods (39.6.9) 860
Shared Key Authentication Methods (39.6.10) 860
Authenticating a Home User (39.6.11) 861
Encryption Methods (39.6.12) 862
Authentication in the Enterprise (39.6.13) 863
WPA3 (39.6.14) 864
WPA3-Personal 864
WPA3-Enterprise 864
Open Networks 865
IoT Onboarding 865
Network Security Summary (39.7) 865
What Did I Learn in This Chapter? (39.7.1) 865
Reflection Questions (39.7.2) 870
Practice 871
Packet Tracer Activities 871
Check Your Understanding Questions 871
Appendix A Answers to the “Check Your Understanding” Questions 875
Online Element
Glossary



9780138321338 TOC 1/8/2024