CCNA学习指南（Exam 640-802 英文版）

Part I Introduction to networking

1 Networks 3

Introduction to Networks 4

Network Characteristics 4

Components 5

Network Locations 7

Local Area Networks 7

Wide Area Networks 7

Network Topologies 9

Physical and Logical Topologies 11

Fully and Partially Meshed Topologies 12

Introduction to Network Security 13

Classes of Attacks 14

Common Threats and Mitigation 15

√Two-Minute Drill 21

Q&A Self Test 23

Self Test Answers 25

2 OSI Reference Model 27

Introduction to the OSI Reference Model 28

Layers of the OSI Reference Model 29

Layer 7： The Application Layer 31

Layer 6： The Presentation Layer 31

Layer 5： The Session Layer 32

Layer 4： The Transport Layer 33

Layer 3： The Network Layer 41

Layer 2： The Data Link Layer 46

Layer 1： The Physical Layer 51

Devices 52

Encapsulation and De-encapsulation 53

Going Down the Protocol Stack 55

Going Up the Protocol Stack 56

Layers and Communication 57

√Two-Minute Drill 62

Q&A Self Test 64

Self Test Answers 67

3 Layer 2 LAN Technologies 69

Ethernet Evolution and Standards 70

Ethernet Operation 71

Ethernet Implementations 72

Framing 73

Addressing 78

Bit Values 78

Power of 2 79

Hexadecimal Conversion 80

MAC Addresses 81

Ethernet Connections 82

Cabling Types 82

Ethernet Media Types 89

√Two-Minute Drill 94

Q&A Self Test 95

Self Test Answers 97

4 Bridges and Switches 99

Problems and Limitations of Ethernet 100

Distance and Extension of LANs 100

Collisions， Collision Domains， and Congestion 101

Solutions to Collision Problems 102

Bridges 102

Switches 105

Bridges versus Switches 105

Methods of Switching 107

Duplexing 109

Switching Functions 111

Learning Function 112

Forwarding Function 114

Loops 121

√Two-Minute Drill 124

Q&A Self Test 125

Self Test Answers 127

5 Wireless 129

Wireless LAN Technologies 130

Narrowband， Broadband， and Packet Data Solutions 130

CSMA/CA 131

Radio Frequency Transmission Factors 132

WLAN Standards 133

RF Bands 133

802.11 Standards 134

WLAN Security 136

WLAN Client Access to the Network 136

Security Solutions 137

WLAN Implementation 141

Access Modes 142

Coverage Areas 143

Data Rates 144

WLAN Devices 145

Access Points 145

Clients 146

Troubleshooting 146

√Two-Minute Drill 150

Q&A Self Test 152

Self Test Answers 155

Part II TCP/IP Protocol Suite

6 TCP/IP and the Internet Layer 159

TCP/IP Protocol Stack 160

Internet Layer 160

Introduction to TCP/IP Addressing 163

TCP/IP Internet Protocols 168

DHCP 168

ARP 170

ICMP 176

TCP/IP Tools for Windows PCs 177

ipconfig Command 177

The ping Command 179

The tracert Command 181

The arp Command 182

√Two-Minute Drill 186

Q&A Self Test 188

Self Test Answers 190

7 IP Addressing and Subnetting 193

IP Addressing Review 194

Distinguishing Between Classes of Addresses 195

IP Address Components 196

Subnetting 197

Subnet Masks 198

Subnet Mask Values 199

IP Address Planning 203

Step 1： Determine Network and Host Requirements 204

Step 2： Satisfy Host and Network Requirements 204

Step 3： Determine the Subnet Mask 206

Step 4： Determine the Network Addresses 206

Step 5： Determine the Directed Broadcast Addresses 208

Step 6： Determine the Host Addresses 209

exercise 7-1： Planning IP Addressing Exercise 210

Determining IP Address Components 211

Six-Step Approach for Determining IP Address Components 212

Example #1 for Determining IP Address Components 213

Example #2 for Determining IP Address Components 215

Example #3 for Determining IP Address Components 216

exercise 7-2： Determining Network， Directed Broadcast， and Host　Components 217

√Two-Minute Drill 220

Q&A Self Test 222

Self Test Answers 224

8 VLSM 227

VLSM 228

Features of VLSM 228

Addressing with VLSM 230

VLSM Example 1 232

VLSM Example 2 234

Route Summarization 235

Advantages of Summarization 236

Classless Interdomain Routing 237

Hierarchical Addressing 238

Routing and Subnet Masks 239

The Routing Table 242

Performing Summarization 243

exercise 8-1： Performing Route Summarization 247

exercise 8-2： Verifying Route Summarization 248

√Two-Minute Drill 252

Q&A Self Test 253

Self Test Answers 256

9 TCP/IP and the Transport Layer 259

Transport Layer Functions 260

Flow Control 260

Reliability 261

Multiplexing 262

Segmentation 262

Transport Layer Protocols 262

Transmission Control Protocol 262

User Datagram Protocol 264

TCP and UDP Applications 266

Ports 267

Application Mapping 268

Session Establishment 270

TCP’s Three-Way Handshake 270

TCP’s Sequencing and Acknowledgments 272

TCP’s Flow Control and Windowing 273

√Two-Minute Drill 276

Q&A Self Test 278

Self Test Answers 280

10 Sending and Receiving TCP/IP Packets 281

Network Components and Addressing Review 282

Layer 1 Components 282

Layer 2 Components 282

Layer 3 Components 283

End-to-End Delivery Example 285

PC-A Acquires Addressing Information 286

PC-A Opens Up a Session to PC-B 287

√Two-Minute Drill 294

Q&A Self Test 295

Self Test Answers 297

Part III Cisco Catalyst Switches

11 Cisco IOS Software 301

Introduction to Cisco Device Configuration 302

Router and Switch Connections 303

Device Startup 307

Command-Line Interface (CLI) 308

CLI Access Modes 310

IOS Basics 312

Command Abbreviation and Completion 312

Context-Sensitive Help 313

Error Messages 314

Entering Commands 315

IOS Feature Example 319

exercise 11-1： Using IOS Features 320

Basic IOS Configuration 321

Accessing Configuration Mode 322

Device Identification 322

Subconfiguration Modes 323

Line Configuration 324

Interface Configuration 327

Basic IOS Security Configuration 331

Physical and Environmental Threats 331

Passwords 332

Login Banners 335

IOS Operation and Verification 337

Show and Debug Command Overview 337

Running and Startup Configuration 338

Device Version Information 341

Interface Information 342

exercise 11-2： Using the CLI to Set Up a Basic Router　Configuration 346

√Two-Minute Drill 351

Q&A Self Test 353

Self Test Answers 355

12 Initial Switch Configuration 357

2960 Overview 358

2960 Chassis 359

2960 LEDs and MODE Button 360

MODE Button 360

Switch Startup 361

Switch Bootup Process 362

System Configuration Dialog 364

Basic Switch Configuration 367

IP Address and Default Gateway 367

Example Configuration 368

exercise 12-1： Configuring the Switches 370

Basic Switch Operation and Verification 372

MAC Address Table 372

Static MAC Addresses 373

exercise 12-2： CAM Tables 374

Port Security Feature 375

Port Security Configuration 375

Port Security Verification 377

√Two-Minute Drill 381

Q&A Self Test 383

Self Test Answers 385

13 VLANs and Trunks 387

VLAN Overview 388

Subnets and VLANs 391

Scalability 392

VLANs and Traffic Types 393

VLAN Membership 394

VLAN Connections 395

Access-Link Connections 396

Trunk Connections 396

VLAN Trunk Protocol 403

VTP Modes 405

VTP Messages 406

VTP Pruning 408

VLAN Configuration 412

Configuring VTP 412

Configuring Trunks 415

exercise 13-1： Configuring Trunks on Your Switches 418

Creating VLANs 419

Basic Troubleshooting of VLANs and Trunks 422

exercise 13-2： Configuring VLANs on Your Switches 424

√Two-Minute Drill 428

Q&A Self Test 430

Self Test Answers 432

14 Switches and Redundancy 433

Layer 2 Redundancy 434

Hierarchical Campus Design 434

Layer 2 Issues 436

Spanning Tree Protocol 438

Bridge Protocol Data Units 439

Root Switch 440

Root Port 442

Designated Port 444

Port States 445

Layer 2 Convergence 447

Per-VLAN STP Plus 449

Simple STP Example 450

Rapid Spanning Tree Protocol 454

Additional Port Roles 455

RSTP BPDUs 455

RSTP Convergence Features 456

RSTP Configuration 457

PVST+ and RSTP Optimization 459

exercise 14-1： Examining STP Information on Your Switches 461

EtherChannels 462

EtherChannel Overview 462

EtherChannel Configuration 464

STP Troubleshooting 465

Loop Identification 465

Configuration Remedies 465

√Two-Minute Drill 468

Q&A Self Test 470

Self Test Answers 472

Part IV Cisco Routers and LANs

15 Routers and Routing 477

Routing Introduction 479

Types of Routes 479

Autonomous Systems 480

Administrative Distance 481

Dynamic Routing Protocols 482

Routing Metrics 483

Distance Vector Protocols 484

Link State Protocols 486

Hybrid Protocols 489

Distance Vector Protocol Problems and Solutions 490

Problem： Convergence 490

Problem： Routing Loops 496

√Two-Minute Drill 504

Q&A Self Test 506

Self Test Answers 508

16 Initial Router Configuration 511

Router Hardware Components 512

Read-Only Memory (ROM) 512

Other Components 513

Router Bootup Process 514

Bootstrap Program 516

System Configuration Dialog 519

Configuration Register 522

AutoSecure 526

Router Configuration 531

Interface Configuration 532

Subnet Zero Configuration 536

Static Host Configuration 536

exercise 16-1： Using IOS Features 538

Router-on-a-Stick 540

Subinterface Configuration 540

Interface Encapsulation 541

Router-on-a-Stick Example Configuration 542

√Two-Minute Drill 546

Q&A Self Test 548

Self Test Answers 550

17 IOS Device Management 553

Router Configuration Files 554

Saving Configuration Files 554

Restoring Configuration Files 556

Creating and Deleting Configuration Files 557

Configuration File Nomenclature 558

Review of Configuration Files 559

exercise 17-1： Manipulating Your Router’s Configuration Files 560

Changes in Your Network 561

Adding Devices 562

Changing Devices 562

IOS Image Files 563

Naming Conventions for IOS Images 564

Before Upgrading the IOS Image 565

Backing Up an IOS Image 566

Loading an IOS Image 566

Remote Access to Your IOS Device 568

SSH vs Telnet Access 569

SSH Configuration 570

Basic Troubleshooting 571

Local ARP Table 572

Cisco Discovery Protocol (CDP) 573

Layer 3 Connectivity Testing 577

Layer 7 Connectivity Testing 584

Debug Overview 587

exercise 17-2： Using the Router’s Troubleshooting Tools 589

√Two-Minute Drill 592

Q&A Self Test 594

Self Test Answers 596

18 Security Device Manager 599

Introduction to SDM 600

PC Requirements 601

Router Requirements and SDM Files 602

Necessary Router Configuration 603

Accessing SDM 605

Basic Router Configuration Using SDM 609

Configure Screens 609

Interfaces 613

DHCP Setup 615

Basic Router Monitoring Using SDM 620

√Two-Minute Drill 624

Q&A Self Test 625

Self Test Answers 627

Part V Routing

19 Basic Routing 631

Static Routes 632

Static Route Configuration 633

Default Route Configuration 634

Default Routes and Distance Vector Protocols 635

Static Route Verification and Troubleshooting 636

exercise 19-1： Static Route Configuration 637

exercise 19-2： Basic IP and Routing Troubleshooting 639

Dynamic Routing Protocol Basics 642

The router Command 643

The network Command 644

RIP 646

RIP Operation 646

RIP Configuration 649

RIP Verification and Troubleshooting 652

exercise 19-3： Configuring RIP 656

exercise 19-4： Basic RIP Troubleshooting 659

√Two-Minute Drill 664

Q&A Self Test 665

Self Test Answers 667

20 OSPF Routing 669

OSPF Overview 670

Hierarchical Design： Areas 671

Metric Structure 673

OSPF Operation 674

Router Identities 674

Finding Neighbors 675

Designated and Backup Designated Routers 676

Sharing Routing Information 678

OSPF Configuration 681

Loopback Interfaces 683

Default Route Propagation 684

OSPF Metric Values 685

OSPF Authentication 686

OSPF Troubleshooting 688

The show ip protocolsCommand 688

The show ip route Command 689

The show ip ospf Command 690

The show ip ospf interface Command 691

The show ip ospf neighbor Command 692

The debug ip ospf adj Command 693

The debug ip ospf events Command 693

The debug ip ospf packet Command 694

exercise 20-1： Configuring OSPF 695

exercise 20-2： Troubleshooting OSPF 697

√Two-Minute Drill 702

Q&A Self Test 704

Self Test Answers 706

21 EIGRP Routing 709

EIGRP Overview 710

Metrics and Interoperability 711

Routing Tables and Updates 711

EIGRP Operation 712

Building Neighbor Relationships 713

Choosing Routes 714

EIGRP Configuration 716

EIGRP Configuration Example 716

Other EIGRP Commands 718

EIGRP Troubleshooting 723

The show ip protocols Command 723

The show ip route Command 724

The show ip eigrp neighbors Command 725

The show ip eigrp topology Command 727

The show ip eigrp interfaces Command 728

The show ip eigrp traffic Command 729

The debug ip eigrpCommand 729

The debug eigrp packetsCommand 730

√Two-Minute Drill 733

Q&A Self Test 734

Self Test Answers 736

Part VI Advanced Cisco Router Features

22 Access Control Lists 739

ACL Overview 740

Definition 740

Types 741

Processing 742

Basic ACL Configuration 745

Creating an ACL 745

Matching on Addresses： Wildcard Masks 746

Activating an ACL 749

ACL Types 751

Standard Numbered ACLs 751

exercise 22-1： Configuring Standard Numbered ACLs 756

Extended Numbered ACLs 759

Named ACLs 765

ACL Remarks 767

Access List Verification 768

ACL Changes 770

ACL Placement 772

Standard ACLs 772

Extended ACLs 774

√Two-Minute Drill 777

Q&A Self Test 779

Self Test Answers 781

23 Address translation 783

Address Translation Overview 784

Running Out of Addresses 784

Private Addresses 785

Address Translation 786

Address Translation Types 787

Terms and Definitions 787

Network Address Translation 787

Port Address Translation 790

Advantages of Address Translation 793

Disadvantages of Address Translation 794

Address Translation Configuration 795

NAT Configuration 795

PAT Configuration 799

Address Translation Verification 800

Translation Process and Troubleshooting 803

Local-to-Global Translation 803

Global-to-Local Translation 804

Address Translation Troubleshooting 805

exercise 23-1： Configuring Static Address Translation 806

exercise 23-2： Configuring Dynamic Address Translation 808

√Two-Minute Drill 812

Q&A Self Test 814

Self Test Answers 817

24 IPv6 819

Necessity of IPv6 820

Growth Issues 820

IPv6 Features 821

IPv6 Addressing 823

IPv6 Address Format 823

Types of IPv6 Addresses 824

Address Assignment 829

Static Address Assignment 829

DHCPv6 829

Stateless Autoconfiguration 830

Routing and IPv6 830

Supported Routing Protocols 831

IPv6 Configuration 834

Enabling IPv6 and Assigning Addresses 834

RIPng 835

√Two-Minute Drill 839

Q&A Self Test 841

Self Test Answers 843

Part VII Cisco Routers and WANs

25 WAN Introduction 847

Wide Area Networking Overview 848

Equipment and Components 848

Connection Types 850

WAN Interfaces on Cisco Routers 856

WAN Cabling 856

Encapsulation Methods 856

HDLC 858

Frame Type 858

Configuring HDLC 859

PPP 860

PPP Components 861

Configuring PPP 863

Troubleshooting PPP 864

PPP Authentication 866

exercise 25-1： Configuring PPP 872

exercise 25-2： Basic PPP Troubleshooting 874

Virtual Private Networks 876

Benefits 877

VPN Types 877

IPSec 880

√Two-Minute Drill 888

Q&A Self Test 890

Self Test Answers 892

26 Frame Relay 895

Virtual Circuits 896

Fully Meshed Design 896

Advantages of VCs 898

Types of VCs 900

Supported Serial Connections 902

Frame Relay Terms 903

LMI 905

DLCIs 907

VC Data Rates 911

Congestion Control 914

Frame Relay Configuration 915

Encapsulation Configuration 915

LMI Configuration 917

Troubleshooting LMI 917

PVC Configuration 920

exercise 26-1： Configuring Frame Relay 927

Non-Broadcast Multi-Access Environments 930

Topology Types 931

Split Horizon Issues 931

Solutions to Split Horizon Problems 933

Subinterfaces 934

exercise 26-2： Configuring Frame Relay with Subinterfaces 941

√Two-Minute Drill 946

Q&A Self Test 948

Self Test Answers 950

Part VIII Appendixes

A About the CD 955

System Requirements 956

Installing and Running the Boson NetSim LE and BEE 956

Boson NetSim LE 956

BEE and Practice Exams 957

CertCams 958

Help 958

Removing Installation(s) 958

Technical Support 958

B Exam Readiness Checklist 959

ICNDv1 (642–822) Exam 960

ICNDv2 (642-816) Exam 965

Index 967

Glossary 985