9780789751096

Prepare for Cisco CCNA Routing and Switching 200-120 exam success with this Cisco Exam Cram from Pearson IT Certification, a leader in IT.

Cisco CCNA Routing and Switching 200-120 Exam Cram is the perfect study guide to help you pass the Cisco CCNA 200-120 exam, providing coverage and practice questions for every exam topic. The book contains an extensive set of preparation tools such as exam objective mapping; a self-assessment section that helps you evaluate your motivations and exam readiness; concise, easy-to-read exam topic overviews; Exam Alerts that highlight key concepts; bullet lists and summaries for easy review; Cram Savers, Cram Quizzes, and chapter-ending practice questions that help you assess your knowledge and test your understanding; Notes that indicate areas of concern or specialty training; Tips to help you build a better foundation of knowledge; and an extensive glossary of terms and acronyms. The book also contains the extremely useful Cram Sheet tear-out that represents a collection of the most difficult-to-remember facts and numbers you should memorize before taking the test. Complementing all these study tools is the powerful Pearson IT Certification Practice Test software, complete with hundreds of exam-realistic practice questions. This assessment software offers you a wealth of customization option and reporting features, allowing you to test your knowledge in study mode, practice exam mode, or flash card mode.

Covers the critical information you’ll need to know to score higher on your CCNA exam!

· Identify the protocols that operate at specific OSI layers

· Learn the details of custom subnetting with IPv4

· Understand and implement IPv6

· Connect, configure, and manage Cisco routers and switches

· Set up security for routers and switches

· Create VLANs and set up switch-to-switch trunk linksFilter traffic from one network to another with access control lists (ACLs)

· Deploy Network Address Translation (NAT) and IOS router DHCP services

· Learn to predict and verify Spanning Tree Protocol (STP)

· Configure and verify OSPFv2, OSPFv3, and EIGRP

· Leverage redundancy protocols including HSRP and GLBP

· Implement WAN technologies including PPP, HDLC, and Frame Relay

· Troubleshoot switches and routers, including routing protocols

Companion CD

The companion CD contains a digital edition of the Cram Sheet and the powerful Pearson IT Certification Practice Test engine, complete with hundreds of exam-realistic questions. The assessment engine offers you a wealth of customization options and reporting features, laying out a complete assessment of your knowledge to help you focus your study where it is needed most.

Pearson IT Certification Practice Test minimum system requirements:

Windows XP (SP3), Windows Vista (SP2), Windows 7, or Windows 8; Microsoft .NET Framework 4.0 Client; Pentium-class 1GHz processor (or equivalent); 512MB RAM;

650MB disk space plus 50MB for each downloaded practice exam; access to the Internet to register and download your practice exams

Mike Valentine has been in the IT field for 16 years, focusing on network design and implementation. He is a Cisco Certified Systems Instructor (#31461) and specializes in Cisco Unified Communications instruction as well as CCNA and CCNP courses. His accessible, humorous, and effective teaching style has demystified Cisco for hundreds of students since he began teaching in 2002.

Keith Barker, CCIE No. 6783 R/S & Security, is a 27-year veteran of the networking industry. He currently works at CBT Nuggets. His past experience includes EDS, Blue Cross, Paramount Pictures, and KnowledgeNET, and he has delivered CCIE-level training for several years.

Michael Valentine has been in the IT field for 16 years, focusing on network design and implementation. He is a Cisco Certified Systems Instructor (#31461) and specializes in Cisco Unified Communications instruction and in CCNA and CCNP courses. His accessible, humorous, and effective teaching style has demystified Cisco for hundreds of students since he began teaching in 2002. Michael has a Bachelor of Arts degree from the University of British Columbia and currently holds CCNA, CCDA, CCNP, and CCNP-Voice certifications. In addition to the popular Exam Cram 2: CCNA and CCENT books, Michael co-authored the Official Certification Guide for CCNA-Voice and has contributed to and served as technical editor for the Cisco Press titles CCNP ONT Official Exam Certification Guide and CCNA Flashcards, among others. Michael has also developed courseware and lab guides for Official Cisco Curriculum courses and custom classes for individuals and corporations.

Keith Barker, CCIE No. 6783 R/S & Security, is a 27-year veteran of the networking industry. He currently works at CBT Nuggets. His past experience includes EDS, Blue Cross, Paramount Pictures, and KnowledgeNET, and he has delivered CCIE-level training for several years. As part of the original set of Cisco VIPs for the Cisco Learning Network, he continues to give back to the community in many ways. He is CISSP, HP, PaloAlto, Brocade, and Juniper certified, loves to teach, and keeps many of his video tutorials at http://www.youtube.com/keith6783. You can reach him on Facebook at “Keith Barker Networking.”

Introduction . . . . . . . . . . . . . . . . . . . 1

Taking a Certification Exam . . . . . . . . . . . . . . . 2

Tracking Your Certification Status . . . . . . . . . . . . 3

How to Prepare for an Exam . . . . . . . . . . . . . . . . 4

What This Book Will Not Do . . . . . . . . . . . . . . . 5

What This Book Is Designed to Do . . . . . . . . . . . . 5

About This Book . . . . . . . . . . . . . . . . . . . 6

CCENT Official Exam Topics . . . .. . . . . 6

Chapter Formats . . . . . . . . . . . . . . . . . 12

Pearson IT Certification Practice Test Engine and Questions on the CD-ROM . . . 14

Install the Software from the CD . . . . . . . . .. . . . . 14

Activate and Download the Practice Exam . . . . . . . . . . 15

Activating Other Exams . . . . . . . . . . . . . . . 16

Contacting the Authors . . . . . . . . . . . 16

Self-Assessment . . . . . . . . . . . . . . . . 17

CCENT in the Real World . . . . . . . . . . . . . 17

The Ideal CCENT Candidate . . . . . . . . . . . . 18

Put Yourself to the Test . . . . . . . . . . 19

CHAPTER 1: Networking Fundamentals . . . . . . . 25

Essential Terms and Components . . . .. . . . . . . . 26

Topologies . . . . . . .. . . . . . . . 27

Ethernet . . . . . . . . . . . . . . 28

WAN Technologies . . . . . . . . . . . 31

Review Questions . . . . . . . . . . . . . . . . . 34

Answers to Review Questions . . . . . . . . . . 36

What Next? . . . . . . . . . . . . . . 37

CHAPTER 2: Network Models . . . . . . . . 39

Cisco Hierarchical Design . . . .. . . . . . . . . . . 40

Access Layer . . . . . . . . . . . . . . . . . 40

Distribution Layer . . . . . . . . . . . . . 41

Core Layer . . . . . . . . . . . . . . . . . 41

Advantages of the Three-Layer Model . . .. . . . . 42

OSI Model . . . . . . . . . . . . . . . . 44

Layer 7: The Application Layer . . . . . . . . . 45

Layer 6: The Presentation Layer . . . . . . . . . 47

Layer 5: The Session Layer . . .. . . . . . . . 47

Layer 4: The Transport Layer . . . . . . . . 47

Layer 3: The Network Layer . . . .. . . . . . . 54

Layer 2: The Data Link Layer . . . . . . . . . . . 56

Layer 1: The Physical Layer . . . . . . . . . . . . . 57

TCP/IP Model . . . . . .. . . . . . . 61

Review Questions . . . . . . . . . .. . . . . . . 64

Answers to Review Questions . . . . . . . . . . . . . 67

CHAPTER 3: Concepts in IP Addressing . . . . . . . 69

Binary . . . . . . . . . . .. . . . . 70

Hexadecimal . . . . . . . .. . . . . . . . 74

Conversion Between Binary, Hex, and Decimal . . . . . . 75

Decimal to Hexadecimal Conversions . . . . . . . . 75

Hexadecimal to Decimal Conversions . . . .. . . . . 75

IP Address Components . . . . . . . . . . . . . 77

Address Class . . . . . . . . . . . . . . 77

Public and Private IP Addresses . . . . . . . . . 78

Default Subnet Mask . . . . . . . . . . . 78

The Network Field . . . . . . .. . . . . . . 79

The Host Field . . . . . . . . . . . . . . . . 80

Nondefault Masks . . . . . . . . . . . . . 80

The Subnet Field . . . . . . . . .. . . . . . 81

Subnetting . . . . . . . . . . . . . . . . . . . . . 82

Address Class and Default Mask . . . . . . . . . . . . . 83

The Increment . . . . . . . . . . . . . . . . . . . 84

Number of Hosts . . . . . . . . .. . . . . . 86

The Broadcast ID . . . . . . . . . . . . . 88

Number of Subnets . . . . . . . . .. . . . . . . 89

Working with Subnetting Questions . . . . . . . 91

The Subnetting Chart . . . . . . . . . . . 93

VLSM . . . . . . . . . . . . . . . . . . . . 96

Route Summarization . . . . . . . . . . . . . . . . 100

Summarization Guidelines . . . . . .. . . . . 102

Determining Summary Addresses . . . . . . . 104

IPv6 . . . . . . . . . . . .. . . . . . . . . 110

IPv6 Address Allocation . . . . . . . . . . . . . . . 112

IPv6 Address Notation . . . . . . . . . . . . 113

Types of IPv6 Addresses . . . . . . . . . . 114

IPv6 Address Configuration . . . . .. . . . 115

IPv6 Router Configuration . . . . . .. . . . . 116

IPv6 Features . . . . . . . . . . . . . . . 117

The IPv6 Header . . . . . . . .. . . . 118

IPv6 Transition Strategies . . . . . . . . . . 119

Review Questions . . . . . . . . . . . .. . . 122

Answers to Review Questions . . . . . . . . . 128

What Next? . . . . . . . . . . . . .. . . . 131

CHAPTER 4: Working with Cisco Equipment. . . . . . . 133

Introducing Your Cisco Gear . . . . . . . . . . . . 134

External Connections . . . . . .. . . . . . . . 135

Other Connections . . . . . . . . . . . . . . . . 139

Connecting and Configuring Cisco Devices . . . . . . . . 141

Device Memory Locations . . . . . . . . . 142

IOS Startup Process . . . . . . .. . . . . 142

Setup Mode . . . . . . . . . . . . . . 144

Configuration Register . . . . .. . . . . 144

Password Recovery . . . . . . . . . . . 145

Command-Line Modes . . . . .. . . . . 146

Command Shortcuts . . . . . . . . . . . . . 148

Context-Sensitive Help . . . . . . . . . 149

Managing IOS Licensing . . . . . . . . . . . 150

Remote Management . . . . . . . . . . . . . . 152

Telnet . . . . . . . . . . . . . . . . . 152

Secure Shell . . . . . . . . . . . . . 154

Cisco Discovery Protocol . . . . . . . . . . . . . . 155

Internet Control Message Protocol . . . . . . 156

Network Time Protocol . . . . . . . . . . . 158

Simple Network Management Protocol. . . . .. . . 158

Syslog . . . . . . . . . . . . . . . . 159

NetFlow . . . . . . . . . . . . . . 159

Basic Switch Configuration . . . . . . . . . . 159

Basic Router Configuration . . . . . . . . . 160

Review Questions . . . . . . . .. . . . . . . 164

Answers to Review Questions . . . . . . . . . . . . . . . 166

What Next? . . . . . . . . . . . . . . . . . . . . 167

CHAPTER 5: Securing Your Cisco Devices . . . . .. . . . . . 169

Securing Routers and Switches . . . . . .. . . . . . . . . . 170

Configuring Password Security . . . . . . . .. . . . 170

Configuring SSH Access to Your Router . . . . . . . . . . 174

External Authentication Methods . . . . . . . . . . . . . 176

Switch Port Security . . . . . . . . . . .. . . . . . . . 178

Security Best Practices for Switches . . . . .. . . . . 178

Review Questions . . . . . . . . . . . . . . . . . . . . 184

Answers to Review Questions . . . . .. . . . . . . . . 186

What Next? . . . . . . . . . . . . . . . . . . . . . . . 187

CHAPTER 6: Basic Switch Operations and Configuration . . . . . . 189

Bridging and Switching . . . . . . . . . . .. . . . . . . . 190

Functions of Bridges and Switches . . . . . . . . . . 191

The Differences Between Switches and Bridges . . . . . . . 195

STP . . . . . . . . . . . . . . .. . . . . . 200

VLAN Concepts and Applications . . . . . . . . . . . . 204

The Definition of a VLAN . . . . . . . . . 206

Benefits of VLANs . . . . . . . .. . . . . . . . 206

Implementing VLANs . . . . . . . . . . 208

VLAN Membership . . . . . . . . . . . . 210

Trunking . . . . . . . . . . . . . . . . . . . . . 212

802.1Q . . . . . . . . . . . . . . . . . . 214

Configuring Switches for Trunking . . . . . . . . . . 215

Review Questions . . . . . . . . . . . . . . . . 219

Answers to Review Questions . . . . . . . . . . . . . 222

What Next? . . . . . . . . . . . . . . . . . 224

CHAPTER 7: Basic Routing . . . . . . 225

Routing Fundamentals . . . . . . . . . . . . . . 226

The Next Hop Concept . . . . . . . . . . 227

Connected Networks . . . . . . . . . . . . 228

Static Routes . . . . . . . . . . . . . . . 229

Default Routes . . . . . . . . . . . . . . 230

Dynamic Routes . . . . . . . . . . 232

Understanding the Router Lookup Process and the IP Route Table . . .. . 235

Inter-VLAN Routing . . . . . . . . . . 242

Router on a Stick . . . . . . . . . 243

L3 Switching . . . . . . . . . . . 245

OSPF . . . . . . . . . . . . . . . . . . . 248

Characteristics . . . . . .. . . . . . . . 249

Configuring Single-Area OSPFv2. . . . . . . . 254

Configuring Single-Area OSPFv3. . . . . . . . . . . 258

Verifying and Troubleshooting OSPF. . . . . . . . 260

Verification of OSPFv3 . . . . . . . . . . . 261

Review Questions . . . . . . . . . . .. . . . . . 265

Answers to Review Questions . . . .. . . . . . 269

CHAPTER 8: Visualizing Data Flow Between Two Hosts on a Network . . . 271

Host-to-Host Direct Communications . . . . . . . . . 272

Host to Host Through a Switch . . . . . . . . . . . 275

Host to Host Through a Router . . . . . . . . . . 278

Review Questions . . . . . . . . . . . . . . . . . . . 283

Answers to Review Questions . . . . . . . . . . . . . 286

What Next? . . . . . . . . . . . . . . 288

CHAPTER 9: IP Access Lists . . . . . . . 289

IP Access Lists as Packet Filters . . . . . . . . . . . . . 290

Types of ACLs . . . . . . . . . . . . . . . 293

Configuring and Implementing . . . . . . . . . . . . . . 296

Configuring Standard ACLs . . . . . . . . . . 297

Configuring Extended ACLs . . . . . . . . . . . 300

Filtering Telnet and SSH Access . . . . . . . . . . 302

Troubleshooting and Verifying ACL Configurations. . . . .. . . . 308

Review Questions . . . . . . . . . . . . . 311

Answers to Review Questions . . . . . . . . . . . . . 316

What Next? . . . . . . . . . . . . . . 318

CHAPTER 10: IP Services . . . . . 319

Network Address Translation . . .. . . . . . . . 320

NAT Terminology . . . . . . . . . . 321

Applications, Advantages, and Disadvantages of NAT . . . . . . . . . 323

Static NAT . . . . . . . . . . . . . . . . . . . 324

Dynamic NAT . . . . .. . . . . . . . . . . 326

PAT . . . . . . . . . . . . . . . . . 328

Verification and Troubleshooting NAT and PAT . . . . . 330

Network Time Protocol . . . . . . . . . . . 334

Configuring an IOS Router as an NTP Client . . . . . . . 335

Verification of NTP . . . . .. . . . . . . . 336

DHCP . . . . . . . . .. . . . . . . . . 338

Configuring an IOS Router as a DHCP Client . . . . . . 338

Configuring an IOS Router as a DHCP Server . . .. . . . 339

Verification of DHCP Operation . . . . . . . . 340

Review Questions . . . . . . .. . . . . . . . . . 343

Answers to Review Questions . . . . . . . . . . . . 345

CHAPTER 11: Troubleshooting . . . . 347

Troubleshoot Layer 1 Problems . . .. . . . . . . . . . . 348

Problems with the Wiring . . . . .. . . . . . . 348

Duplex . . . . . . . . . . . . . . . . . . 349

Finding the Errors . . . . . . .. . . . . . 349

Verify and Troubleshoot VLANs and Port Membership . . . .. . . . 353

Troubleshooting VLANs . . . . .. . . . . . 354

Verify Trunk Configuration and Operation . . . .. . . . . . 357

Is the Link Up and Configured? . . . . . . . . . . 357

VLANs Must Exist for the Trunk to Support Them . . . . . . 357

Administrative Versus Operational . . . . . . . . . 358

Troubleshoot Problems with IP Addressing and Host Configurations . . 361

Verify Hosts Have Correct IP Addresses . . . . . . . . . . 362

How to Remotely Change a Cisco IP Address . . . . . . . . 362

Making Sure That We Have a Default Gateway on Hosts . . . . . . 362

Troubleshooting NAT . . . . . . . .. . . . . . . . . 363

Troubleshoot ACL Issues . . . . . . . . . . . . 365

Review Questions . . . . . . . . . . . . . . . . . . . 368

Answers to Review Questions . . . . . . . . . . . . 375

CHAPTER 12: Advanced Switching Concepts . . . . . . . 381

Spanning Tree Protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 382

Root Election . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 385

STP Communication with BPDUs . . . . . . . . . . . . . . . . . . . . . . 386

Port Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 386

Port Role Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 390

Convergence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 390

RSTP Enhancements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 392

Understanding Per-VLAN Spanning Tree (PVST) . . . . . . . . . . 393

Setting the Spanning-Tree Mode . . . . . . . . . . . . . . . . . . . . . . . 395

Configuring and Verifying PVST . . . . . . . . . . . . . . . . . . . . . . . 395

EtherChannel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 402

Configuring EtherChannel . . . . . . . . . . . . . . . . . . . . . . . . . . . 404

Verifying EtherChannel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 407

Review Questions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 414

Answers to Review Questions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 417

CHAPTER 13: Advanced Router Operation . . . . . . . . . 419

Router IOS and Configuration File Management . . . . . . . . . . . . . . . . 420

Back Up and Restore IOS . . . . . . . . . . . . . . . . . . . . . . . . . . . . 421

OSPF . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 423

Advanced OSPF Concepts . . . . . . . . . . . . . . . . . . . . . . . . . . . . 424

Multi-Area OSPF . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 429

Implementing Multi-Area OSPFv2 . . . . . . . . . . . . . . . . . . . . . . 432

Verifying and Troubleshooting OSPFv2 . . . . . . . . . . . . . . . . . . 435

Configuring Multi-Area OSPFv3 . . . . . . . . . . . . . . . . . . . . . . . 437

EIGRP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 442

Characteristics of EIGRP . . . . . . . . . . . . . . . . . . . . . . . . . . . . 443

Implementing EIGRP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 447

Verifying and Troubleshooting EIGRP . . . . . . . . . . . . . . . . . . . 448

Review Questions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 452

Answers to Review Questions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 455

CHAPTER 14: Advanced IP Services . . . . . . . . . 457

Recognize High Availability (FHRP) . . . . . . . . . . . . . . . . . . . . . . . . . 458

Hot Standby Router Protocol . . . . . . . . . . . . . . . . . . . . . . . . . 458

Gateway Load Balancing Protocol (GLBP) . . . . . . . . . . . . . . . . 461

Virtual Router Redundancy Protocol (VRRP) . . . . . . . . . . . . . . 462

Configure and Verify Syslog . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 464

Describe SNMP v2 and v3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 468

Utilize Netflow Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 470

Review Questions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 473

Answers to Review Questions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 477

CHAPTER 15: WAN Operation . . . .. . . . . . . 479

WAN Technologies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 480

Encapsulation Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 482

Frame Relay . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 489

Review Questions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 501

Answers to Review Questions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 503

CHAPTER 16: Advanced Troubleshooting . . . . .. . . . 505

Troubleshoot and Resolve Spanning Tree Operation Issues . . . . . . . . . 506

Troubleshoot and Resolve Routing Issues . . . . . . . . . . . . . . . . . . . . . 511

Troubleshoot and Resolve OSPF Problems . . . . . . . . . . . . . . . . . . . . 514

Troubleshoot and Resolve EIGRP Problems . . . . . . . . . . . . . . . . . . . 519

Troubleshoot and Resolve Inter-VLAN Routing Problems . . . . . . . . . 523

Troubleshoot and Resolve WAN Implementation Issues . . . . . . . . . . . 525

Monitor NetFlow Statistics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 529

Troubleshoot EtherChannel Problems . . . . . . . . . . . . . . . . . . . . . . . 531

Review Questions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 535

Answers to Review Questions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 537

Practice Exam 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 539

Answer Key to Practice Exam 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 575

Answers at a Glance to Practice Exam 1 . . . . . . . . . . . . . . . . . . . . . . 575

Answers with Explanations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 576

Practice Exam 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 587

Answer Key to Practice Exam 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 625

Answers at a Glance to Practice Exam 2 . . . . . . . . . . . . . . . . . . . . . . 625

Answers with Explanations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 626

Glossary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 635

Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 653

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CCNA Routing and Switching 200-120 Exam Cram

CCNA Routing and Switching 200-120 Exam Cram

0789751097

Summary

Author Biography

Table of Contents

Supplemental Materials