Published by Cisco Press (April 1, 2022) © 2022
Cisco Networking AcademyNetworking Essentials Companion Guide is the official supplemental textbook for the Networking Essentials course in the Cisco Networking Academy.
Networking is at the heart of the digital transformation. The network is essential to many business functions today, including business-critical data and operations, cybersecurity, and so much more. A wide variety of career paths rely on the network, so it's important to understand what the network can do, how it operates, and how to protect it.
This is a great course for developers, data scientists, cybersecurity specialists, and other professionals looking to broaden their networking domain knowledge. It's also an excellent launching point for students pursuing a wide range of career pathways—from cybersecurity to software development to business and more.
The Companion Guide is designed as a portable desk reference to use anytime, anywhere to reinforce the material from the course and organize your time.
The book's features help you focus on important concepts to succeed in this course:
* Key terms: Refer to the lists of networking vocabulary introduced and highlighted in context in each chapter.
* Glossary: Consult the comprehensive Glossary with more than 250 terms.
* Summary of Activities and Labs: Maximize your study time with this complete list of all associated practice exercises at the end of each chapter.
* Check Your Understanding: Evaluate your readiness with the end-of-chapter questions that match the style of questions you see in the online course quizzes. The answer key explains each answer.
Introduction xxvii
Chapter 1 Communications in a Connected World 1
Objectives 1
Key Terms 1
Introduction (1.0) 2
Network Types (1.1) 3
Everything Is Online (1.1.1) 3
Who Owns "The Internet"? (1.1.2) 3
Local Networks (1.1.3) 3
Mobile Devices (1.1.5) 7
Connected Home Devices (1.1.6) 10
Other Connected Devices (1.1.7) 12
Data Transmission (1.2) 15
Types of Personal Data (1.2.2) 15
Common Methods of Data Transmission (1.2.4) 16
Bandwidth and Throughput (1.3) 17
Bandwidth (1.3.1) 17
Throughput (1.3.3) 18
Clients and Servers (1.4) 19
Client and Server Roles (1.4.1) 19
Peer-to-Peer Networks (1.4.2) 20
Peer-to-Peer Applications (1.4.3) 21
Multiple Roles in the Network (1.4.4) 22
Network Components (1.5) 23
Network Infrastructure (1.5.2) 23
End Devices (1.5.3) 25
Summary (1.6) 26
Practice 27
Check Your Understanding 27
Chapter 2 Online Communications 31
Objectives 31
Key Terms 31
Introduction (2.0) 32
Wireless Networks (2.1) 32
Mobile Telephones (2.1.2) 32
Cell Phone Network (2.1.3) 32
Other Wireless Networks (2.1.5) 33
Local Network Connections (2.2) 34
LAN Components (2.2.2) 34
End Device Addressing (2.2.4) 39
Manual and Automatic Address Assignment (2.2.6) 40
Network Documentation (2.3) 41
Device Names and Address Planning (2.3.1) 41
Network Topologies and Representations (2.3.2) 42
Logical Network Information (2.3.4) 43
Summary (2.4) 45
Practice 46
Check Your Understanding Questions 46
Chapter 3 Explore Networks with Packet Tracer 49
Objectives 49
Key Terms 49
Introduction (3.0) 50
Packet Tracer Network Simulator (3.1) 50
Packet Tracer Installation (3.2) 50
The Packet Tracer User Interface (3.3) 51
Locate and Deploy Devices (3.3.2) 52
Packet Tracer Network Configuration (3.4) 53
GUI and CLI Configuration in Packet Tracer (3.4.2) 54
Summary (3.5) 59
Practice 61
Check Your Understanding Questions 61
Chapter 4 Build a Simple Network 67
Objectives 67
Key Terms 67
Introduction (4.0.1) 68
Network Media Types (4.1) 68
Three Media Types (4.1.2) 68
Common Network Cables (4.1.3) 69
Ethernet Cabling (4.2) 71
Twisted-Pair Cables (4.2.1) 71
Types of Twisted-Pair Cables (4.2.2) 72
Coaxial and Fiber-Optic Cabling (4.3) 75
Cable TV and Satellite Cables (4.3.1) 75
Fiber-Optic Cables (4.3.2) 76
Twisted-Pair Operation (4.4) 78
Twisted-Pair Wiring Schemes (4.4.1) 78
Twisted-Pair Transmit and Receive Pairs (4.4.2) 79
Verify Connectivity (4.5) 79
Using the ping Command (4.5.2) 80
The traceroute Command (4.5.3) 81
Summary (4.6) 83
Practice 85
Check Your Understanding Questions 85
Chapter 5 Communication Principles 89
Objectives 89
Key Terms 89
Introduction (5.0.1) 90
The Rules (5.1) 90
The Three Elements (5.1.1) 90
Communication Protocols (5.1.2) 91
Why Protocols Matter (5.1.3) 93
Communication Standards (5.2) 95
The Internet and Standards (5.2.2) 95
Network Standards Organizations (5.2.3) 95
Network Communication Models (5.3) 96
The Protocol Stack (5.3.3) 97
The TCP/IP Model (5.3.4) 98
The OSI Reference Model (5.3.5) 99
Upper and Lower Layers of the OSI Model (5.3.6) 100
OSI Model and TCP/IP Model Comparison (5.3.7) 101
Ethernet (5.4) 103
The Rise of Ethernet (5.4.1) 103
Ethernet Evolution (5.4.2) 104
The Ethernet MAC Address (5.4.4) 105
Summary (5.5) 107
Practice 108
Check Your Understanding Questions 108
Chapter 6 Network Design and the Access Layer 111
Objectives 111
Key Terms 111
Introduction (6.0.1) 112
Encapsulation and the Ethernet Frame (6.1) 112
Encapsulation (6.1.2) 112
Ethernet Frame (6.1.3) 114
Hierarchical Network Design (6.2) 115
Physical and Logical Addresses (6.2.2) 115
Hierarchical Analogy (6.2.5) 117
Benefits of a Hierarchical Design (6.2.7) 117
Access, Distribution, and Core (6.2.8) 119
The Access Layer (6.3) 120
Access Layer Devices (6.3.1) 121
Ethernet Hubs (6.3.2) 121
Ethernet Switches (6.3.4) 123
The MAC Address Table (6.3.6) 124
Broadcast Containment (6.4) 126
Ethernet Broadcasts in the Local Network (6.4.2) 126
Broadcast Domains (6.4.3) 127
Access Layer Communication (6.4.4) 128
ARP (6.4.6) 129
Summary (6.5) 131
Practice 133
Check Your Understanding Questions 133
Chapter 7 Routing Between Networks 137
Objectives 137
Key Terms 137
Introduction (7.0.1) 138
The Need for Routing (7.1) 138
Criteria for Dividing the Local Network (7.1.2) 138
When Routing Is Needed (7.1.3) 141
The Routing Table (7.2) 142
Path Selection (7.2.2) 142
Packet Forwarding (7.2.5) 143
Routing Table Entries (7.2.7) 145
The Default Gateway (7.2.8) 146
Create a LAN (7.3) 147
Local-Area Networks (7.3.1) 147
Local and Remote Network Segments (7.3.2) 148
Summary (7.4) 152
Practice 153
Check Your Understanding Questions 153
Chapter 8 The Internet Protocol 157
Objectives 157
Key Terms 157
Introduction (8.0.1) 158
Purpose of the IPv4 Address (8.1) 158
The IPv4 Address (8.1.1) 158
Binary Conversion of an IPv4 Address (8.2) 159
IPv4 Addressing (8.2.1) 159
Binary to Decimal (8.2.3) 160
The IPv4 Address Structure (8.3) 162
Networks and Hosts (8.3.2) 162
Logical AND (8.3.5) 163
Calculate Whether the Destination Is Local or Remote (8.3.6) 164
Calculate the Number of Hosts (8.3.7) 165
Classful IPv4 Addressing (8.4) 166
Classful and Classless Addressing (8.4.1) 166
Public and Private IPv4 Addresses (8.5) 168
Private IPv4 Addressing (8.5.1) 168
Assignment of IPv4 Addresses (8.5.2) 169
Unicast, Broadcast, and Multicast Addresses (8.6) 171
Unicast Transmission (8.6.2) 171
Broadcast Transmission (8.6.4) 172
Multicast Transmission (8.6.6) 173
Summary (8.7) 175
Practice 177
Check Your Understanding Questions 177
Chapter 9 Dynamic Addressing with DHCP 181
Objectives 181
Key Terms 181
Introduction (9.0.1) 182
Static and Dynamic Addressing (9.1) 182
Static IPv4 Address Assignment (9.1.1) 182
Dynamic IPv4 Address Assignment (9.1.2) 183
DHCP Servers (9.1.3) 184
DHCPv4 Configuration (9.2) 185
DHCPv4 Operation (9.2.2) 185
DHCP Service Configuration (9.2.4) 186
Summary (9.3) 188
Practice 189
Check Your Understanding Questions 189
Chapter 10 IPv4 and IPv6 Address Management 193
Objectives 193
Key Terms 193
Introduction (10.0.1) 194
Network Boundaries (10.1) 194
Routers as Gateways (10.1.2) 194
Routers as Boundaries Between Networks (10.1.3) 195
Network Address Translation (10.2) 196
NAT Operation (10.2.2) 196
IPv4 Issues (10.3) 198
Need for IPv6 (10.3.1) 198
IPv6 Address Size (10.3.2) 200
IPv4 and IPv6 Coexistence (10.3.4) 201
IPv6 Features (10.4) 203
IPv6 Autoconfiguration and Link-Local Addresses (10.4.3) 203
IPv6 Address Representation (10.4.5) 204
Summary (10.5) 206
Practice 207
Check Your Understanding Questions 208
Chapter 11 Transport Layer Services 211
Objectives 211
Key Terms 211
Introduction (11.0.1) 212
The Client/Server Relationship (11.1) 212
Client and Server Interaction (11.1.1) 212
Client Requests a Web Page (11.1.3) 213
URI, URN, and URL (11.1.4) 214
TCP and UDP (11.2) 215
Protocol Operations (11.2.1) 215
TCP and UDP (11.2.3) 216
TCP Reliability (11.2.4) 216
UDP Best Effort Delivery (11.2.5) 217
Port Numbers (11.3) 218
TCP and UDP Port Numbers (11.3.2) 218
Destination and Source Port Numbers (11.3.3) 220
Socket Pairs (11.3.4) 221
The netstat Command (11.3.5) 223
Summary (11.4) 224
Practice 225
Check Your Understanding Questions 225
Chapter 12 Application Layer Services 229
Objectives 229
Key Terms 229
Introduction (12.0.1) 230
Network Application Services (12.1) 230
Common Network Application Services (12.1.1) 230
Domain Name System (12.2) 231
Domain Name Translation (12.2.1) 231
DNS Servers (12.2.3) 232
Web Clients and Servers (12.3) 233
HTTP and HTML (12.3.2) 233
FTP Clients and Servers (12.4) 234
File Transfer Protocol (12.4.1) 235
FTP Client Software (12.4.3) 236
Virtual Terminals (12.5) 237
Telnet (12.5.2) 237
Security Issues with Telnet (12.5.3) 238
Email and Messaging (12.6) 239
Email Clients and Servers (12.6.1) 239
Email Protocols (12.6.2) 240
Text Messaging (12.6.3) 242
Internet Phone Calls (12.6.4) 243
Summary (12.7) 244
Practice 246
Check Your Understanding Questions 246
Chapter 13 Build a Home Network 249
Objectives 249
Key Terms 249
Introduction (13.0.1) 250
Home Network Basics (13.1) 250
Connecting Home Devices (13.1.1) 250
Components of a Home Network (13.1.2) 251
Typical Home Network Routers (13.1.3) 252
Network Technologies in the Home (13.2) 253
The Electromagnetic Spectrum (13.2.1) 253
LAN Wireless Frequencies (13.2.2) 254
Wired Network Technologies (13.2.3) 255
Wireless Standards (13.3) 257
Wi-Fi Networks (13.3.1) 257
Wireless Settings (13.3.2) 257
Wireless Traffic Controls (13.4) 259
Wireless Channels (13.4.1) 259
Wireless as a Shared Media (13.4.2) 260
Set Up a Home Router (13.5) 261
First Time Setup (13.5.1) 261
Design Considerations (13.5.2) 261
MAC Address Filtering (13.5.3) 263
Summary (13.6) 265
Practice 267
Check Your Understanding Questions 267
Chapter 14 Connect to the Internet 271
Objectives 271
Key Terms 271
Introduction (14.0.1) 272
ISP Connectivity Options (14.1) 272
ISP Services (14.1.1) 272
ISP Connections (14.1.2) 273
Cable and DSL Connections (14.1.3) 274
Additional Connectivity Options (14.1.4) 275
Network Virtualization (14.2) 276
Cloud Computing (14.2.2) 276
Types of Clouds (14.2.3) 276
Cloud Services (14.2.4) 277
Cloud Computing and Virtualization (14.2.5) 277
Advantages of Virtualization (14.2.6) 279
Hypervisors (14.2.7) 279
Network Virtualization (14.2.9) 281
Control Plane and Data Plane (14.2.10) 282
Network Virtualization and SDN (14.2.11) 283
SDN Architecture (14.2.12) 283
Mobile Device Connectivity (14.3) 284
Mobile Devices and Wi-Fi (14.3.1) 284
Wi-Fi Settings (14.3.2) 285
Configure Mobile Wi-Fi Connectivity (14.3.3) 286
Configure Cellular Data Settings (14.3.4) 288
Simple Connectivity with Bluetooth (14.3.6) 290
Bluetooth Pairing (14.3.7) 290
Summary (14.4) 293
Practice 295
Check Your Understanding Questions 295
Chapter 15 Security Considerations 299
Objectives 299
Key Terms 299
Introduction (15.0.1) 300
Security Threats (15.1) 300
Types of Threats (15.1.1) 300
Internal and External Threats (15.1.2) 301
Social Engineering Attacks (15.2) 302
Overview of Social Engineering (15.2.1) 302
Types of Social Engineering Attacks (15.2.2) 303
Malware (15.3) 304
Malicious Software (15.3.1) 305
Types of Malware (15.3.2) 305
Spyware (15.3.3) 306
Adware and Popups (15.3.4) 306
Botnets and Zombies (15.3.5) 307
Denial-of-Service Attacks (15.4) 308
Denial of Service (15.4.1) 308
Distributed Denial of Service (15.4.2) 309
Brute Force (15.4.3) 310
Security Tools (15.5) 310
Security Practices and Procedures (15.5.1) 310
Security Tools and Applications (15.5.2) 312
Patches and Updates (15.5.3) 313
Antimalware Software (15.6) 314
Signs of Infections (15.6.1) 314
Antivirus Software (15.6.2) 315
Antispam Software (15.6.3) 316
Antispyware Software (15.6.4) 316
Additional Safeguards (15.6.5) 317
Summary (15.7) 318
Practice 321
Check Your Understanding Questions 321
Chapter 16 Configure Network and Device Security 325
Objectives 325
Key Terms 325
Introduction (16.0.1) 326
Wireless Security Measures (16.1) 326
Wireless Vulnerabilities (16.1.1) 326
A Comprehensive Security Plan (16.1.2) 327
SSID Broadcasts (16.1.4) 333
Changing Default Settings (16.1.5) 334
MAC Address Filtering (16.1.6) 335
Implement Wireless Security (16.2) 336
Open Authentication (16.2.1) 336
Authentication and Association (16.2.2) 336
Authentication Protocols (16.2.3) 337
Configure a Firewall (16.3) 338
Firewall Overview (16.3.1) 338
Firewall Operation (16.3.2) 338
The DMZ (16.3.3) 339
Port Forwarding (16.3.4) 340
Port Triggering (16.3.5) 341
Summary (16.4) 344
Practice 345
Check Your Understanding Questions 346
Chapter 17 Cisco Switches and Routers 349
Objectives 349
Key Terms 349
Introduction (17.0.1) 350
Cisco Switches (17.1) 350
Connect More Devices (17.1.1) 350
Cisco LAN Switches (17.1.2) 351
LAN Switch Components (17.1.5) 354
Switch Boot Process (17.2) 355
Power Up the Switch (17.2.1) 355
In-Band and Out-of-Band Management (17.2.3) 358
IOS Startup Files (17.2.4) 358
Cisco Routers (17.3) 359
Router Components (17.3.2) 360
Router Interface Ports (17.3.3) 360
Router Boot Process (17.4) 361
Power Up the Router (17.4.1) 361
Management Ports (17.4.2) 365
Summary (17.5) 367
Practice 368
Check Your Understanding Questions 368
Chapter 18 The Cisco IOS Command Line 373
Objectives 373
Key Terms 373
Introduction (18.0.1) 374
Navigate the IOS (18.1) 374
The Cisco IOS Command-Line Interface (18.1.1) 374
Primary Command Modes (18.1.2) 375
A Note About Syntax Checker Activities (18.1.5) 376
The Command Structure (18.2) 376
Basic IOS Command Structure (18.2.1) 376
IOS Command Syntax (18.2.2) 377
Hotkeys and Shortcuts (18.2.4) 378
View Device Information (18.3) 380
Show Commands (18.3.2) 381
Summary (18.4) 387
Practice 388
Check Your Understanding Questions 388
Chapter 19 Build a Small Cisco Network 391
Objectives 391
Key Terms 391
Introduction (19.0.1) 392
Basic Switch Configuration (19.1) 392
Basic Switch Configuration Steps (19.1.1) 392
Switch Virtual Interface Configuration (19.1.2) 394
Configure Initial Router Settings (19.2) 395
Basic Router Configuration Steps (19.2.1) 395
Basic Router Configuration Example (19.2.2) 396
Secure the Devices (19.3) 398
Password Recommendations (19.3.1) 398
Secure Remote Access (19.3.2) 399
Configure SSH (19.3.3) 400
Verify SSH (19.3.5) 402
Connecting the Switch to the Router (19.4) 404
Default Gateway for a Host (19.4.1) 404
Default Gateway on a Switch (19.4.2) 406
Summary (19.5) 409
Practice 411
Check Your Understanding Questions 412
Chapter 20 Troubleshoot Common Network Problems 415
Objectives 415
Key Terms 415
Introduction (20.0.1) 416
The Troubleshooting Process (20.1) 416
Network Troubleshooting Overview (20.1.1) 416
Gather Information (20.1.2) 416
Structured Troubleshooting Methods (20.1.3) 418
Guidelines for Selecting a Troubleshooting Method (20.1.4) 422
Physical Layer Problems (20.2) 423
Common Layer 1 Problems (20.2.1) 423
Wireless Router LEDs (20.2.2) 424
Cabling Problems (20.2.3) 426
Troubleshooting Commands (20.3) 426
Overview of Troubleshooting Commands (20.3.1) 426
The ipconfig Command (20.3.2) 427
The ping Command (20.3.4) 430
Ping Results (20.3.5) 431
Divide and Conquer with ping (20.3.7) 432
The tracert Command (20.3.8) 433
The netstat Command (20.3.9) 434
The nslookup Command (20.3.10) 436
Troubleshoot Wireless Issues (20.4) 438
Causes of Wireless Issues (20.4.1) 438
Authentication and Association Errors (20.4.2) 439
Common Internet Connectivity Issues (20.5) 441
DHCP Server Configuration Errors (20.5.1) 441
Check Internet Configuration (20.5.2) 442
Check Firewall Settings (20.5.3) 444
Customer Support (20.6) 444
Sources of Help (20.6.1) 445
When to Call for Help (20.6.2) 445
Support Desk Interaction (20.6.3) 446
Issue Resolution (20.6.4) 447
Support Desk Tickets and Work Orders (20.6.5) 448
Summary (20.7) 450
Practice 453
Check Your Understanding Questions 454
Appendix A Answers to the "Check Your Understanding" Questions 459
Glossary 471
9780137660483 TOC 1/25/2022
Chapter 1 Communications in a Connected World 1
Objectives 1
Key Terms 1
Introduction (1.0) 2
Network Types (1.1) 3
Everything Is Online (1.1.1) 3
Who Owns "The Internet"? (1.1.2) 3
Local Networks (1.1.3) 3
Mobile Devices (1.1.5) 7
Connected Home Devices (1.1.6) 10
Other Connected Devices (1.1.7) 12
Data Transmission (1.2) 15
Types of Personal Data (1.2.2) 15
Common Methods of Data Transmission (1.2.4) 16
Bandwidth and Throughput (1.3) 17
Bandwidth (1.3.1) 17
Throughput (1.3.3) 18
Clients and Servers (1.4) 19
Client and Server Roles (1.4.1) 19
Peer-to-Peer Networks (1.4.2) 20
Peer-to-Peer Applications (1.4.3) 21
Multiple Roles in the Network (1.4.4) 22
Network Components (1.5) 23
Network Infrastructure (1.5.2) 23
End Devices (1.5.3) 25
Summary (1.6) 26
Practice 27
Check Your Understanding 27
Chapter 2 Online Communications 31
Objectives 31
Key Terms 31
Introduction (2.0) 32
Wireless Networks (2.1) 32
Mobile Telephones (2.1.2) 32
Cell Phone Network (2.1.3) 32
Other Wireless Networks (2.1.5) 33
Local Network Connections (2.2) 34
LAN Components (2.2.2) 34
End Device Addressing (2.2.4) 39
Manual and Automatic Address Assignment (2.2.6) 40
Network Documentation (2.3) 41
Device Names and Address Planning (2.3.1) 41
Network Topologies and Representations (2.3.2) 42
Logical Network Information (2.3.4) 43
Summary (2.4) 45
Practice 46
Check Your Understanding Questions 46
Chapter 3 Explore Networks with Packet Tracer 49
Objectives 49
Key Terms 49
Introduction (3.0) 50
Packet Tracer Network Simulator (3.1) 50
Packet Tracer Installation (3.2) 50
The Packet Tracer User Interface (3.3) 51
Locate and Deploy Devices (3.3.2) 52
Packet Tracer Network Configuration (3.4) 53
GUI and CLI Configuration in Packet Tracer (3.4.2) 54
Summary (3.5) 59
Practice 61
Check Your Understanding Questions 61
Chapter 4 Build a Simple Network 67
Objectives 67
Key Terms 67
Introduction (4.0.1) 68
Network Media Types (4.1) 68
Three Media Types (4.1.2) 68
Common Network Cables (4.1.3) 69
Ethernet Cabling (4.2) 71
Twisted-Pair Cables (4.2.1) 71
Types of Twisted-Pair Cables (4.2.2) 72
Coaxial and Fiber-Optic Cabling (4.3) 75
Cable TV and Satellite Cables (4.3.1) 75
Fiber-Optic Cables (4.3.2) 76
Twisted-Pair Operation (4.4) 78
Twisted-Pair Wiring Schemes (4.4.1) 78
Twisted-Pair Transmit and Receive Pairs (4.4.2) 79
Verify Connectivity (4.5) 79
Using the ping Command (4.5.2) 80
The traceroute Command (4.5.3) 81
Summary (4.6) 83
Practice 85
Check Your Understanding Questions 85
Chapter 5 Communication Principles 89
Objectives 89
Key Terms 89
Introduction (5.0.1) 90
The Rules (5.1) 90
The Three Elements (5.1.1) 90
Communication Protocols (5.1.2) 91
Why Protocols Matter (5.1.3) 93
Communication Standards (5.2) 95
The Internet and Standards (5.2.2) 95
Network Standards Organizations (5.2.3) 95
Network Communication Models (5.3) 96
The Protocol Stack (5.3.3) 97
The TCP/IP Model (5.3.4) 98
The OSI Reference Model (5.3.5) 99
Upper and Lower Layers of the OSI Model (5.3.6) 100
OSI Model and TCP/IP Model Comparison (5.3.7) 101
Ethernet (5.4) 103
The Rise of Ethernet (5.4.1) 103
Ethernet Evolution (5.4.2) 104
The Ethernet MAC Address (5.4.4) 105
Summary (5.5) 107
Practice 108
Check Your Understanding Questions 108
Chapter 6 Network Design and the Access Layer 111
Objectives 111
Key Terms 111
Introduction (6.0.1) 112
Encapsulation and the Ethernet Frame (6.1) 112
Encapsulation (6.1.2) 112
Ethernet Frame (6.1.3) 114
Hierarchical Network Design (6.2) 115
Physical and Logical Addresses (6.2.2) 115
Hierarchical Analogy (6.2.5) 117
Benefits of a Hierarchical Design (6.2.7) 117
Access, Distribution, and Core (6.2.8) 119
The Access Layer (6.3) 120
Access Layer Devices (6.3.1) 121
Ethernet Hubs (6.3.2) 121
Ethernet Switches (6.3.4) 123
The MAC Address Table (6.3.6) 124
Broadcast Containment (6.4) 126
Ethernet Broadcasts in the Local Network (6.4.2) 126
Broadcast Domains (6.4.3) 127
Access Layer Communication (6.4.4) 128
ARP (6.4.6) 129
Summary (6.5) 131
Practice 133
Check Your Understanding Questions 133
Chapter 7 Routing Between Networks 137
Objectives 137
Key Terms 137
Introduction (7.0.1) 138
The Need for Routing (7.1) 138
Criteria for Dividing the Local Network (7.1.2) 138
When Routing Is Needed (7.1.3) 141
The Routing Table (7.2) 142
Path Selection (7.2.2) 142
Packet Forwarding (7.2.5) 143
Routing Table Entries (7.2.7) 145
The Default Gateway (7.2.8) 146
Create a LAN (7.3) 147
Local-Area Networks (7.3.1) 147
Local and Remote Network Segments (7.3.2) 148
Summary (7.4) 152
Practice 153
Check Your Understanding Questions 153
Chapter 8 The Internet Protocol 157
Objectives 157
Key Terms 157
Introduction (8.0.1) 158
Purpose of the IPv4 Address (8.1) 158
The IPv4 Address (8.1.1) 158
Binary Conversion of an IPv4 Address (8.2) 159
IPv4 Addressing (8.2.1) 159
Binary to Decimal (8.2.3) 160
The IPv4 Address Structure (8.3) 162
Networks and Hosts (8.3.2) 162
Logical AND (8.3.5) 163
Calculate Whether the Destination Is Local or Remote (8.3.6) 164
Calculate the Number of Hosts (8.3.7) 165
Classful IPv4 Addressing (8.4) 166
Classful and Classless Addressing (8.4.1) 166
Public and Private IPv4 Addresses (8.5) 168
Private IPv4 Addressing (8.5.1) 168
Assignment of IPv4 Addresses (8.5.2) 169
Unicast, Broadcast, and Multicast Addresses (8.6) 171
Unicast Transmission (8.6.2) 171
Broadcast Transmission (8.6.4) 172
Multicast Transmission (8.6.6) 173
Summary (8.7) 175
Practice 177
Check Your Understanding Questions 177
Chapter 9 Dynamic Addressing with DHCP 181
Objectives 181
Key Terms 181
Introduction (9.0.1) 182
Static and Dynamic Addressing (9.1) 182
Static IPv4 Address Assignment (9.1.1) 182
Dynamic IPv4 Address Assignment (9.1.2) 183
DHCP Servers (9.1.3) 184
DHCPv4 Configuration (9.2) 185
DHCPv4 Operation (9.2.2) 185
DHCP Service Configuration (9.2.4) 186
Summary (9.3) 188
Practice 189
Check Your Understanding Questions 189
Chapter 10 IPv4 and IPv6 Address Management 193
Objectives 193
Key Terms 193
Introduction (10.0.1) 194
Network Boundaries (10.1) 194
Routers as Gateways (10.1.2) 194
Routers as Boundaries Between Networks (10.1.3) 195
Network Address Translation (10.2) 196
NAT Operation (10.2.2) 196
IPv4 Issues (10.3) 198
Need for IPv6 (10.3.1) 198
IPv6 Address Size (10.3.2) 200
IPv4 and IPv6 Coexistence (10.3.4) 201
IPv6 Features (10.4) 203
IPv6 Autoconfiguration and Link-Local Addresses (10.4.3) 203
IPv6 Address Representation (10.4.5) 204
Summary (10.5) 206
Practice 207
Check Your Understanding Questions 208
Chapter 11 Transport Layer Services 211
Objectives 211
Key Terms 211
Introduction (11.0.1) 212
The Client/Server Relationship (11.1) 212
Client and Server Interaction (11.1.1) 212
Client Requests a Web Page (11.1.3) 213
URI, URN, and URL (11.1.4) 214
TCP and UDP (11.2) 215
Protocol Operations (11.2.1) 215
TCP and UDP (11.2.3) 216
TCP Reliability (11.2.4) 216
UDP Best Effort Delivery (11.2.5) 217
Port Numbers (11.3) 218
TCP and UDP Port Numbers (11.3.2) 218
Destination and Source Port Numbers (11.3.3) 220
Socket Pairs (11.3.4) 221
The netstat Command (11.3.5) 223
Summary (11.4) 224
Practice 225
Check Your Understanding Questions 225
Chapter 12 Application Layer Services 229
Objectives 229
Key Terms 229
Introduction (12.0.1) 230
Network Application Services (12.1) 230
Common Network Application Services (12.1.1) 230
Domain Name System (12.2) 231
Domain Name Translation (12.2.1) 231
DNS Servers (12.2.3) 232
Web Clients and Servers (12.3) 233
HTTP and HTML (12.3.2) 233
FTP Clients and Servers (12.4) 234
File Transfer Protocol (12.4.1) 235
FTP Client Software (12.4.3) 236
Virtual Terminals (12.5) 237
Telnet (12.5.2) 237
Security Issues with Telnet (12.5.3) 238
Email and Messaging (12.6) 239
Email Clients and Servers (12.6.1) 239
Email Protocols (12.6.2) 240
Text Messaging (12.6.3) 242
Internet Phone Calls (12.6.4) 243
Summary (12.7) 244
Practice 246
Check Your Understanding Questions 246
Chapter 13 Build a Home Network 249
Objectives 249
Key Terms 249
Introduction (13.0.1) 250
Home Network Basics (13.1) 250
Connecting Home Devices (13.1.1) 250
Components of a Home Network (13.1.2) 251
Typical Home Network Routers (13.1.3) 252
Network Technologies in the Home (13.2) 253
The Electromagnetic Spectrum (13.2.1) 253
LAN Wireless Frequencies (13.2.2) 254
Wired Network Technologies (13.2.3) 255
Wireless Standards (13.3) 257
Wi-Fi Networks (13.3.1) 257
Wireless Settings (13.3.2) 257
Wireless Traffic Controls (13.4) 259
Wireless Channels (13.4.1) 259
Wireless as a Shared Media (13.4.2) 260
Set Up a Home Router (13.5) 261
First Time Setup (13.5.1) 261
Design Considerations (13.5.2) 261
MAC Address Filtering (13.5.3) 263
Summary (13.6) 265
Practice 267
Check Your Understanding Questions 267
Chapter 14 Connect to the Internet 271
Objectives 271
Key Terms 271
Introduction (14.0.1) 272
ISP Connectivity Options (14.1) 272
ISP Services (14.1.1) 272
ISP Connections (14.1.2) 273
Cable and DSL Connections (14.1.3) 274
Additional Connectivity Options (14.1.4) 275
Network Virtualization (14.2) 276
Cloud Computing (14.2.2) 276
Types of Clouds (14.2.3) 276
Cloud Services (14.2.4) 277
Cloud Computing and Virtualization (14.2.5) 277
Advantages of Virtualization (14.2.6) 279
Hypervisors (14.2.7) 279
Network Virtualization (14.2.9) 281
Control Plane and Data Plane (14.2.10) 282
Network Virtualization and SDN (14.2.11) 283
SDN Architecture (14.2.12) 283
Mobile Device Connectivity (14.3) 284
Mobile Devices and Wi-Fi (14.3.1) 284
Wi-Fi Settings (14.3.2) 285
Configure Mobile Wi-Fi Connectivity (14.3.3) 286
Configure Cellular Data Settings (14.3.4) 288
Simple Connectivity with Bluetooth (14.3.6) 290
Bluetooth Pairing (14.3.7) 290
Summary (14.4) 293
Practice 295
Check Your Understanding Questions 295
Chapter 15 Security Considerations 299
Objectives 299
Key Terms 299
Introduction (15.0.1) 300
Security Threats (15.1) 300
Types of Threats (15.1.1) 300
Internal and External Threats (15.1.2) 301
Social Engineering Attacks (15.2) 302
Overview of Social Engineering (15.2.1) 302
Types of Social Engineering Attacks (15.2.2) 303
Malware (15.3) 304
Malicious Software (15.3.1) 305
Types of Malware (15.3.2) 305
Spyware (15.3.3) 306
Adware and Popups (15.3.4) 306
Botnets and Zombies (15.3.5) 307
Denial-of-Service Attacks (15.4) 308
Denial of Service (15.4.1) 308
Distributed Denial of Service (15.4.2) 309
Brute Force (15.4.3) 310
Security Tools (15.5) 310
Security Practices and Procedures (15.5.1) 310
Security Tools and Applications (15.5.2) 312
Patches and Updates (15.5.3) 313
Antimalware Software (15.6) 314
Signs of Infections (15.6.1) 314
Antivirus Software (15.6.2) 315
Antispam Software (15.6.3) 316
Antispyware Software (15.6.4) 316
Additional Safeguards (15.6.5) 317
Summary (15.7) 318
Practice 321
Check Your Understanding Questions 321
Chapter 16 Configure Network and Device Security 325
Objectives 325
Key Terms 325
Introduction (16.0.1) 326
Wireless Security Measures (16.1) 326
Wireless Vulnerabilities (16.1.1) 326
A Comprehensive Security Plan (16.1.2) 327
SSID Broadcasts (16.1.4) 333
Changing Default Settings (16.1.5) 334
MAC Address Filtering (16.1.6) 335
Implement Wireless Security (16.2) 336
Open Authentication (16.2.1) 336
Authentication and Association (16.2.2) 336
Authentication Protocols (16.2.3) 337
Configure a Firewall (16.3) 338
Firewall Overview (16.3.1) 338
Firewall Operation (16.3.2) 338
The DMZ (16.3.3) 339
Port Forwarding (16.3.4) 340
Port Triggering (16.3.5) 341
Summary (16.4) 344
Practice 345
Check Your Understanding Questions 346
Chapter 17 Cisco Switches and Routers 349
Objectives 349
Key Terms 349
Introduction (17.0.1) 350
Cisco Switches (17.1) 350
Connect More Devices (17.1.1) 350
Cisco LAN Switches (17.1.2) 351
LAN Switch Components (17.1.5) 354
Switch Boot Process (17.2) 355
Power Up the Switch (17.2.1) 355
In-Band and Out-of-Band Management (17.2.3) 358
IOS Startup Files (17.2.4) 358
Cisco Routers (17.3) 359
Router Components (17.3.2) 360
Router Interface Ports (17.3.3) 360
Router Boot Process (17.4) 361
Power Up the Router (17.4.1) 361
Management Ports (17.4.2) 365
Summary (17.5) 367
Practice 368
Check Your Understanding Questions 368
Chapter 18 The Cisco IOS Command Line 373
Objectives 373
Key Terms 373
Introduction (18.0.1) 374
Navigate the IOS (18.1) 374
The Cisco IOS Command-Line Interface (18.1.1) 374
Primary Command Modes (18.1.2) 375
A Note About Syntax Checker Activities (18.1.5) 376
The Command Structure (18.2) 376
Basic IOS Command Structure (18.2.1) 376
IOS Command Syntax (18.2.2) 377
Hotkeys and Shortcuts (18.2.4) 378
View Device Information (18.3) 380
Show Commands (18.3.2) 381
Summary (18.4) 387
Practice 388
Check Your Understanding Questions 388
Chapter 19 Build a Small Cisco Network 391
Objectives 391
Key Terms 391
Introduction (19.0.1) 392
Basic Switch Configuration (19.1) 392
Basic Switch Configuration Steps (19.1.1) 392
Switch Virtual Interface Configuration (19.1.2) 394
Configure Initial Router Settings (19.2) 395
Basic Router Configuration Steps (19.2.1) 395
Basic Router Configuration Example (19.2.2) 396
Secure the Devices (19.3) 398
Password Recommendations (19.3.1) 398
Secure Remote Access (19.3.2) 399
Configure SSH (19.3.3) 400
Verify SSH (19.3.5) 402
Connecting the Switch to the Router (19.4) 404
Default Gateway for a Host (19.4.1) 404
Default Gateway on a Switch (19.4.2) 406
Summary (19.5) 409
Practice 411
Check Your Understanding Questions 412
Chapter 20 Troubleshoot Common Network Problems 415
Objectives 415
Key Terms 415
Introduction (20.0.1) 416
The Troubleshooting Process (20.1) 416
Network Troubleshooting Overview (20.1.1) 416
Gather Information (20.1.2) 416
Structured Troubleshooting Methods (20.1.3) 418
Guidelines for Selecting a Troubleshooting Method (20.1.4) 422
Physical Layer Problems (20.2) 423
Common Layer 1 Problems (20.2.1) 423
Wireless Router LEDs (20.2.2) 424
Cabling Problems (20.2.3) 426
Troubleshooting Commands (20.3) 426
Overview of Troubleshooting Commands (20.3.1) 426
The ipconfig Command (20.3.2) 427
The ping Command (20.3.4) 430
Ping Results (20.3.5) 431
Divide and Conquer with ping (20.3.7) 432
The tracert Command (20.3.8) 433
The netstat Command (20.3.9) 434
The nslookup Command (20.3.10) 436
Troubleshoot Wireless Issues (20.4) 438
Causes of Wireless Issues (20.4.1) 438
Authentication and Association Errors (20.4.2) 439
Common Internet Connectivity Issues (20.5) 441
DHCP Server Configuration Errors (20.5.1) 441
Check Internet Configuration (20.5.2) 442
Check Firewall Settings (20.5.3) 444
Customer Support (20.6) 444
Sources of Help (20.6.1) 445
When to Call for Help (20.6.2) 445
Support Desk Interaction (20.6.3) 446
Issue Resolution (20.6.4) 447
Support Desk Tickets and Work Orders (20.6.5) 448
Summary (20.7) 450
Practice 453
Check Your Understanding Questions 454
Appendix A Answers to the "Check Your Understanding" Questions 459
Glossary 471
9780137660483 TOC 1/25/2022