CCENT Cisco Certified Entry Networking Technician Study Guide

Todd Lammle, CCSI, CCNA, CCNP, CCSP, CCVP, is the authority on Cisco networking. He has been involved in computers and networking with Fortune 500 companies for almost 30 years. Todd is President of GlobalNet Training, Inc., a networking integration and training firm based in Dallas. He is the bestselling author of numerous Cisco books, including the popular CCNA: Cisco Certified Network Associate Study Guide , with over 200,000 copies in print. He can be reached through his website at www.lammle.com.

Introduction xix Exam Objectives xxvii Assessment Test xxx Chapter 1 Internetworking 1 Internetworking Basics 2 Addressing 3 Internetworking Models 11 The Layered Approach 11 Advantages of Reference Models 12 The OSI Reference Model 12 The Application Layer 15 The Presentation Layer 15 The Session Layer 16 The Transport Layer 16 The Network Layer 22 The Data Link Layer 24 The Physical Layer 27 Ethernet Networking 28 Collision Domain 28 Broadcast Domain 29 CSMA/CD 29 Half- and Full-Duplex Ethernet 31 Ethernet at the Data Link Layer 32 Ethernet at the Physical Layer 38 Ethernet Cabling 43 Straight-Through Cable 43 Crossover Cable 44 Rolled Cable 44 Data Encapsulation 47 Summary 51 Exam Essentials 52 Written Lab 1 54 Written Lab 1.1: OSI Questions 54 Written Lab 1.2: Defining the OSI Layers and Devices 55 Written Lab 1.3: Identifying Collision and Broadcast Domains 56 Written Lab 1.4: Binary/Decimal/Hexadecimal Conversion 57 Review Questions 60 Chapter 2 Internet Protocols 65 TCP/IP and the DoD Model 66 The Process/Application Layer Protocols 68 The Host-to-Host Layer Protocols 75 The Internet Layer Protocols 85 IP Addressing 95 IP Terminology 95 The Hierarchical IP Addressing Scheme 96 Private IP Addresses 101 IPv4 Address Types 102 Layer 2 Broadcasts 103 Layer 3 Broadcasts 103 Unicast Address 103 Multicast Address 104 Summary 104 Exam Essentials 105 Written Lab 2 107 Review Questions 108 Chapter 3 IP Subnetting, Troubleshooting IP, and Introduction to NAT 113 Subnetting Basics 114 IP Subnet-Zero 115 How to Create Subnets 116 Subnet Masks 117 Classless Inter-Domain Routing (CIDR) 118 Subnetting Class C Addresses 120 Subnetting Class B Addresses 130 Subnetting Class A Addresses 137 Troubleshooting IP Addressing 140 Determining IP Address Problems 143 Introduction to Network Address Translation (NAT) 148 Types of Network Address Translation 149 NAT Names 150 How NAT Works 150 Summary 152 Exam Essentials 153 Written Labs 3 154 Written Lab 3.1: Written Subnet Practice #1 154 Written Lab 3.2: Written Subnet Practice #2 155 Written Lab 3.3: Written Subnet Practice #3 155 Review Questions 156 hapter 4 Cisco's Internetworking Operating System (IOS) 161 The IOS User Interface 163 Cisco Router IOS 163 Connecting to a Cisco Router 163 Bringing Up a Router 165 Command-Line Interface (CLI) 169 Entering the CLI 169 Overview of Router Modes 170 CLI Prompts 170 Editing and Help Features 173 Gathering Basic Routing Information 178 Router and Switch Administrative Configurations 179 Hostnames 180 Banners 180 Setting Passwords 182 Setting Interface Descriptions 190 Router Interfaces 192 Bringing Up an Interface 195 Configuring an IP Address on an Interface 196 Viewing, Saving, and Erasing Configurations 201 Deleting the Configuration and Reloading the Router 202 Verifying Your Configuration 203 Summary 213 Exam Essentials 213 Written Lab 4 216 Hands-on Labs 217 Hands-on Lab 4.1: Erasing an Existing Configuration 217 Hands-on Lab 4.2: Exploring User, Privileged, and Configuration Modes 218 Hands-on Lab 4.3: Using the Help and Editing Features 218 Hands-on Lab 4.4: Saving a Router Configuration 220 Hands-on Lab 4.5: Setting Passwords 220 Hands-on Lab 4.6: Setting the Hostname, Descriptions, IP Address, and Clock Rate 222 Review Questions 225 Chapter 5 Managing a Cisco Internetwork 231 The Internal Components of a Cisco Router 232 The Router Boot Sequence 233 Managing Configuration Register 234 Understanding the Configuration Register Bits 234 Checking the Current Configuration Register Value 236 Changing the Configuration Register 237 Recovering Passwords 238 Boot System Commands 242 Backing Up and Restoring the Cisco IOS 243 Verifying Flash Memory 244 Backing Up the Cisco IOS 245 Restoring or Upgrading the Cisco Router IOS 246 Using the Cisco IOS File System (Cisco IFS) 247 Backing Up and Restoring the Cisco Configuration 252 Backing Up the Cisco Router Configuration 252 Restoring the Cisco Router Configuration 254 Erasing the Configuration 255 Using the Cisco IOS File System to Manage Your Router's Configuration (Cisco IFS) 256 Using Cisco Discovery Protocol 258 Getting CDP Timers and Holdtime Information 258 Gathering Neighbor Information 259 Gathering Interface Traffic Information 264 Gathering Port and Interface Information 264 Documenting a Network Topology Using CDP 267 Using Telnet 270 Telnetting into Multiple Devices Simultaneously 272 Checking Telnet Connections 273 Checking Telnet Users 273 Closing Telnet Sessions 274 Resolving Hostnames 274 Building a Host Table 275 Using DNS to Resolve Names 277 Checking and Troubleshooting Network Connectivity 279 Using the ping Command 280 Using the traceroute Command 280 Debugging 282 Using the show processes Command 284 Summary 285 Exam Essentials 286 Written Lab 5 287 Written Lab 5.1 287 Written Lab 5.2 288 Hands-on Labs 288 Hands-on Lab 5.1: Backing Up Your Router IOS 289 Hands-on Lab 5.2: Upgrading or Restoring Your Router IOS 289 Hands-on Lab 5.3: Backing Up the Router Configuration 290 Hands-on Lab 5.4: Using the Cisco Discovery Protocol (CDP) 290 Hands-on Lab 5.5: Using Telnet 291 Hands-on Lab 5.6: Resolving Hostnames 292 Review Questions 294 Chapter 6 IP Routing 299 Routing Basics 301 The IP Routing Process 303 Testing Your IP Routing Understanding 309 Configuring IP Routing 313 Configuring IP Routing in the Network 327 Static Routing 327 Default Routing 338 Dynamic Routing 341 Routing Protocol Basics 341 Distance-Vector Routing Protocols 343 Routing Loops 345 Routing Information Protocol 347 RIP Timers 348 Configuring RIP Routing 348 Verifying the RIP Routing Tables 351 Configuring RIP Routing Example 2 353 Holding Down RIP Propagations 354 RIP Version 2 355 Verifying Your Configurations 358 The show ip protocols Command 358 The debug ip rip Command 360 Enabling RIPv2 on the Internetwork 363 Summary 367 Exam Essentials 368 Written Lab 6 369 Hands-on Labs 370 Hands-on Lab 6.1: Creating Static Routes 371 Hands-on Lab 6.2: Configuring RIP Routing 372 Review Questions 374 Chapter 7 Layer 2 Switching 381 Before Layer 2 Switching 382 Switching Services 385 Limitations of Layer 2 Switching 386 Bridging vs. LAN Switching 387 Three Switch Functions at Layer 2 387 Address Learning 388 Forward/Filter Decisions 389 Port Security 391 Cisco Catalyst Switches 392 S1 394 S2 395 Core 396 Summary 398 Exam Essentials 399 Written Lab 7 399 Review Questions 400 Chapter 8 Wireless Technologies 407 Introducing Wireless Technology 408 The 802.11 Standards 410 2.4GHz (802.11b) 412 2.4GHz (802.11g) 413 5GHz (802.11a) 414 Comparing 802.11 415 2.4GHz/5GHz (802.11n) 416 Basic Service Sets 417 BSS/IBSS 418 ESS 419 Wireless Security 419 Open Access 420 SSIDs, WEP, and MAC Address Authentication 420 WPA or WPA 2 Pre-Shared Key 421 Summary 422 Exam Essentials 423 Written Lab 8 423 Review Questions 424 Chapter 9 Security 429 Introduction to Security 430 Recognizing Security Threats 431 Common Attack Profiles 432 Mitigating Security Threats 435 Mitigating Password, Router, and Switch Attacks 436 Switch Port Security 437 Virtual Private Networks 440 IPsec 442 Summary 442 Exam Essentials 443 Written Lab 9 443 Review Questions 444 Chapter 10 Introduction to Wide Area Networks 449 Introduction to Wide Area Networks 450 Defining WAN Terms 451 WAN Connection Types 452 WAN Support 453 Cabling the Wide Area Network 455 Serial Transmission 455 Data Terminal Equipment and Data Communication Equipment 456 High-Level Data-Link Control (HDLC) Protocol 457 Point-to-Point Protocol 459 PPP Session Establishment 460 PPP Authentication Methods 461 Configuring PPP on Cisco Routers 462 Configuring PPP Authentication 462 Verifying PPP Encapsulation 463 Summary 464 Exam Essentials 465 Written Lab 10 466 Hands-on Labs 466 Hands-on Lab 10.1: Configuring PPP Encapsulation and Authentication 466 Hands-on Lab 10.2: Configuring and Monitoring HDLC 468 Review Questions 469 Appendix A Answers to Written Labs 475 Chapter 1: Internetworking 476 Written Lab 1.1 476 Written Lab 1.2 477 Written Lab 1.3 477 Written Lab 1.4 478 Chapter 2: Internet Protocols 481 Written Lab 2 481 Chapter 3: IP Subnetting, Troubleshooting IP, and Introduction to NAT 481 Written Lab 3.1 481 Written Lab 3.2 482 Written Lab 3.3 483 Chapter 4: Cisco's Internetworking Operating System (IOS) 484 Written Lab 4 484 Chapter 5: Managing a Cisco Internetwork 485 Written Lab 5.1 485 Written Lab 5.2 485 Chapter 6: IP Routing 486 Written Lab 6 486 Chapter 7: Layer 2 Switching 486 Written Lab 7 486 Chapter 8: Wireless Technologies 487 Written Lab 8 487 Chapter 9: Security 487 Written Lab 9 487 Chapter 10: Introduction to Wide Area Networks 488 Written Lab 10 488 Appendix B Answers to Review Questions 489 Chapter 1: Internetworking 490 Chapter 2: Internet Protocols 492 Chapter 3: IP Subnetting, Troubleshooting IP, and Introduction to NAT 493 Chapter 4: Cisco's Internetworking Operating System (IOS) 496 Chapter 5: Managing a Cisco Internetwork 497 Chapter 6: IP Routing 499 Chapter 7: Layer 2 Switching 501 Chapter 8: Wireless Technologies 503 Chapter 9: Security 504 Chapter 10: Introduction to Wide Area Networks 506 Appendix C About the Additional Study Tools 509 Additional Study Tools 510 Sybex Test Engine 510 Electronic Flashcards 510 Study Sheets 510 Todd Lammle Videos 511 Todd Lammle Audios 511 PDF of Glossary of Terms 511 Adobe Reader 511 System Requirements 511 Using the Study Tools 511 Troubleshooting 512 Customer Care 512 Index 513