CompTIA.Network+.N10-004.pdf

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Expand your exam prep FEATURED ON THE CD-ROM Deluxe Edition with this Deluxe guide Bonus Content with Network+ Virtual Lab Prepare for CompTIA’s new Network+ exam with this Deluxe version of Sybex’s popular CompTIA Network+ Study Guide. In STUDY GUIDE addition to comprehensive coverage of exam essentials by top Deluxe Edition Includes Real-World Scenarios, Written Labs, networking authority and bestselling author Todd Lammle, this and Leading-Edge Exam Prep Software Featuring: CompTIA Deluxe version includes six practice exams and bonus content featuring the Network+ Virtual Lab. Start your preparation today Custom Test Engine with Six Practice Exams with: Exclusive Network+ Virtual Lab Network Simulator SYBEX TEST ENGINE: Test your knowledge with advanced Full coverage of all exam objectives in a systematic approach, so you testing software. Includes all chapter Hundreds of Sample Questions can be confident you’re getting the instruction you need for the exam review questions and bonus exams. Electronic Flashcards Network+ Virtual Lab to give you hands-on practice and reinforce Entire Book in PDF Network+ critical skills Real-world scenarios that put what you’ve learned in the context of actual job roles Over 300 electronic flashcards to help you practice, practice, practice Challenging review questions in each chapter to prepare you for exam day Exam Essentials, a key feature in each chapter that identifies critical ELECTRONIC FLASHCARDS: Reinforce your understanding with CompTIA Network+ flashcards that can run on your PC. areas you must become proficient in before taking the exam ® A handy tear card that maps every official exam objective to the corresponding chapter in the book, so you can track your exam prep objective by objective Look inside for complete coverage of all exam objectives. Deluxe NETWORK+ VIRTUAL LAB: Get hands-on practice in a virtual network. www.sybex.com Also on CD, you’ll find the entire ABOUT THE AUTHOR ® book in searchable and printable PDF. Study anywhere, any time, and Todd Lammle, CCNA, Network+, is the authority on networking. He has been involved approach the exam with confidence. in computers and networking with Fortune 500 companies for over 25 years. Todd is Presi- dent of GlobalNet Training, Inc., a networking integration and training firm based in Dallas. He is also the bestselling author of numerous Cisco books, including the popular CCNA: Cisco Certified Network Associate Study Guide, with over 200,000 copies in print. You can reach C AT E G O RY COMPUTERS/Certification Guides Lammle STUDY GUIDE Exclusive cutting-edge Network+ Virtual Lab software him through his website at www.lammle.com. Exam N10-004 ISBN 978-0-470-42748-4 Go to www.SybexTestSuccess.com for more information about our online test prep product, powered by ExamWeb. Exam N10-004 Todd Lammle $89.99 US $107.99 CN SERIOUS SKILLS. 27484ffirs.indd 2 3/9/09 8:53:57 AM  CompTIA Network+ ® Deluxe Study Guide 27484ffirs.indd 1 3/9/09 8:53:57 AM 27484ffirs.indd 2 3/9/09 8:53:57 AM  CompTIA Network+ Deluxe ® Deluxe Study Guide Todd Lammle 27484ffirs.indd 3 3/9/09 8:53:58 AM  Acquisitions Editor: Jeff Kellum Development Editor: Susan Herman Technical Editors: Steven Johnson and Derek Lewis Production Editor: Christine O’Connor Copy Editor: Tiffany Taylor Production Manager: Tim Tate Vice President and Executive Group Publisher: Richard Swadley Vice President and Publisher: Neil Edde Project Manager 1: Laura Moss-Hollister Associate Producer: Shawn Patrick Media Quality Assurance: Angie Denny Book Designer: Judy Fung, Bill Gibson Compositor: Craig Woods, Happenstance Type-O-Rama Proofreader: Publication Services, Inc. Indexer: Jack Lewis Project Coordinator, Cover: Lynsey Stanford Cover Designer: Ryan Sneed Copyright © 2009 by Wiley Publishing, Inc., Indianapolis, Indiana Published simultaneously in Canada ISBN: 978-0-470-42748-4 No part of this publication may be reproduced, stored in a retrieval system or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, scanning or otherwise, except as permitted under Sections 107 or 108 of the 1976 United States Copyright Act, without either the prior written permission of the Publisher, or authorization through payment of the appropriate per-copy fee to the Copyright Clearance Center, 222 Rosewood Drive, Danvers, MA 01923, (978) 750-8400, fax (978) 646-8600. Requests to the Publisher for permission should be addressed to the Permissions Department, John Wiley & Sons, Inc., 111 River Street, Hoboken, NJ 07030, (201) 748-6011, fax (201) 748-6008, or online at http://www.wiley.com/go/permissions. 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The fact that an organization or Web site is referred to in this work as a citation and/or a potential source of fur- ther information does not mean that the author or the publisher endorses the information the organization or Web site may provide or recommendations it may make. Further, readers should be aware that Internet Web sites listed in this work may have changed or disappeared between when this work was written and when it is read. For general information on our other products and services or to obtain technical support, please contact our Customer Care Department within the U.S. at (877) 762-2974, outside the U.S. at (317) 572-3993 or fax (317) 572-4002. Wiley also publishes its books in a variety of electronic formats. Some content that appears in print may not be available in electronic books. Library of Congress Cataloging-in-Publication Data. Lammle, Todd. CompTIA Network+ study guide (Exam N10-004) / Todd Lammle. — 1st ed. p. cm. ISBN 978-0-470-42747-7 (paper/cd-rom) -- ISBN 978-0-470-42748-4 (cloth/cd-rom) 1. Computer networks— Examinations—Study guides. 2. Electronic data processing personnel--Certification. I. Title. TK5105.5.L3555 2009 004.6076—dc22 2009001904 TRADEMARKS: Wiley, the Wiley logo, and the Sybex logo are trademarks or registered trademarks of John Wiley & Sons, Inc. and/or its affiliates, in the United States and other countries, and may not be used without written permission. Network+ is a registered trademark of The Computing Technology Industry Association, Inc. All other trademarks are the property of their respective owners. Wiley Publishing, Inc., is not associated with any product or vendor mentioned in th is book. 10 9 8 7 6 5 4 3 2 1 27484ffirs.indd 4 3/9/09 8:53:58 AM  Sybex is an independent entity from CompTIA and is not affiliated with CompTIA in any manner. Neither CompTIA nor Sybex warrants that use of this publication will ensure passing the relevant exam. Network+ is either a registered trademark or trademark of CompTIA in the United States and/or other countries. The logo of the CompTIA Authorized Quality Curriculum (CAQC) program and the status of this or other training material as “Authorized” under the CompTIA Authorized Quality Curriculum program signifies that, in CompTIA’s opinion, such training material covers the content of the CompTIA’s related certification exam. CompTIA has not reviewed or approved the accuracy of the contents of this training material and specifically disclaims any warranties of merchantability or fitness for a particular purpose. CompTIA makes no guarantee concerning the success of persons using any such “Authorized” or other training material in order to prepare for any CompTIA certification exam. The contents of this training material were created for the CompTIA Network+ exam covering CompTIA certification objectives that were current as of 2008. How to Become CompTIA Certified: This training material can help you prepare for and pass a related CompTIA certification exam or exams. In order to achieve CompTIA certification, you must register for and pass a CompTIA certifica- tion exam or exams. In order to become CompTIA certified, you must: 1. Select a certification exam provider. 2. Register for and schedule a time to take the CompTIA certification exam(s) at a convenient location. 3. Read and sign the Candidate Agreement, which will be presented at the time of the exam(s). 4. Take and pass the CompTIA certification exam(s). For more information about CompTIA’s certification process, and to learn more about their industry acceptance, benefits, or program news, please visit http://www.comptia.org/certification. CompTIA is a non-profit information technology (IT) trade association. CompTIA’s certifications are designed by subject matter experts from across the IT industry. Each CompTIA certification is vendor-neutral, covers multiple technologies, and requires demonstration of skills and knowledge widely sought after by the IT industry. To contact CompTIA with any questions or comments please email them at: [email protected] Sybex is an independent entity from CompTIA and is not affiliated with CompTIA in any manner. Neither CompTIA nor Sybex warrants that use of this publication will ensure passing the relevant exam. Network+ is either a registered trademark or trademark of CompTIA in the United States and/or other countries. 27484ffirs.indd 5 3/9/09 8:53:58 AM 27484ffirs.indd 6 3/9/09 8:53:58 AM  Dear Reader, Thank you for choosing CompTIA Network+ Deluxe Study Guide. This book is part of a family of premium-quality Sybex books, all of which are written by outstanding authors who combine practical experience with a gift for teaching. Sybex was founded in 1976. More than thirty years later, we’re still committed to producing consistently exceptional books. With each of our titles we’re working hard to set a new stan- dard for the industry. From the paper we print on, to the authors we work with, our goal is to bring you the best books available. I hope you see all that reflected in these pages. I’d be very interested to hear your comments and get your feedback on how we’re doing. Feel free to let me know what you think about this or any other Sybex book by sending me an email at [email protected], or if you think you’ve found a technical error in this book, please visit http://sybex.custhelp.com. Cus- tomer feedback is critical to our efforts at Sybex. Best regards, Neil Edde Vice President and Publisher Sybex, an Imprint of Wiley 27484ffirs.indd 7 3/9/09 8:53:58 AM  Acknowledgments Monica Lammle’s writing style, editing ability, encouragement, and dedication to ensuring that my books are concise yet highly readable has been invaluable to the success of this and many other projects. Susan Herman was the development editor of this, the newest book in the Sybex Comp- TIA series. Thank you, Susan, for having the patience of Job, and for working so hard on this book with me. I’m so happy (and relieved) that you took on the job and, most of all, that you didn’t run screaming from the room the next day! Jeff Kellum is instrumental to my success in the Cisco world and is my acquisitions editor for this new CompTIA Network+ book. Jeff, thanks for your guidance and continued patience for all our books we’ve published together! In addition, Christine O’Connor was an excellent production editor and she worked really hard to get the book done as quickly as possible, without missing the small mistakes that are so easy to over look. I am always very pleased when I hear that she will be working with me on a new project. Tiffany Taylor was latest copy editor, and she was patient, helpful, and detailed, but yet worked extremely hard to get this book out the shelf as fast as possible, and for that I thank her tremendously. Steven Johnson literally hashed and rehashed each topic in this guide with me at all hours of the day and night, scrutinizing the material until we both agreed it was verifiably solid. Thank you, Steve! I also want to mention Patrick Conlan, who tech-edited my CCNA book and is writing the Sybex Cisco Network Professional’s Advanced Internetworking Guide. Pat was very helpful in throwing ideas at me for this book, and was the photographer for all the pictures I put in this book. 27484ffirs.indd 8 3/9/09 8:53:59 AM  About the Author Todd Lammle, CompTIA Network+, CCSI, CCNA/CCNP, CCSP/CCVP, MCSE, CEH/ CHFI, FCC RF Licensed, is the authority on Network Certification and internetworking. He is a world-renowned author, speaker, trainer, and consultant. Todd has over 25 years of experience working with LANs, WANs, and large licensed and unlicensed wireless net- works. He’s president and CEO of GlobalNet Training and Consulting, Inc., a network- integration and training firm based in Dallas, Texas. You can reach Todd through his forum at www.lammle.com. 27484ffirs.indd 9 3/9/09 8:53:59 AM 27484ffirs.indd 10 3/9/09 8:53:59 AM  Contents at a Glance Introduction xxvii Assessment Test xlviii Chapter 1 Introduction to Networks 1 Chapter 2 The Open Systems Interconnection Specifications 33 Chapter 3 Networking Topologies, Connectors, and Wiring Standards 61 Chapter 4 The Current Ethernet Specifications 97 Chapter 5 Networking Devices 131 Chapter 6 Introduction to Internet Protocol (IP) 177 Chapter 7 IP Addressing 215 Chapter 8 IP Subnetting, Troubleshooting IP, and Introduction to NAT 241 Chapter 9 Introduction to IP Routing 287 Chapter 10 Routing Protocols 311 Chapter 11 Switching and Virtual LANs (VLANs) 339 Chapter 12 Wireless Technologies 377 Chapter 13 Authentication and Access Control 423 Chapter 14 Network Threats and Mitigation 463 Chapter 15 Physical and Hardware Security 499 Chapter 16 Wide Area Networks 545 Chapter 17 Command-Line Tools 575 Chapter 18 Software and Hardware Tools 629 Chapter 19 Network Troubleshooting 659 Chapter 20 Management, Monitoring, and Optimization 699 Appendix A Subnetting Class A 731 Appendix B About the Companion CD 741 Glossary 745 Index 791 27484ffirs.indd 11 3/9/09 8:53:59 AM 27484ffirs.indd 12 3/9/09 8:53:59 AM  Contents Introduction xxvii Assessment Test xlviii Chapter 1 Introduction to Networks 1 First Things First: What’s a Network? 2 The Local Area Network (LAN) 3 Common Network Components 5 Virtual LANs (VLANs) 8 Wide Area Network (WAN) 9 Virtual Private Networks (VPNs) 10 Network Architecture: Peer-to-Peer or Client/Server? 11 Physical Network Topologies 13 Bus Topology 14 Star Topology 15 Ring Topology 16 Mesh Topology 17 Point-to-Point Topology 18 Point-to-Multipoint Topology 19 Hybrid Topology 20 Topology Selection, Backbones, and Segments 21 Selecting the Right Topology 21 Summary 22 Exam Essentials 23 Written Labs 24 Review Questions 25 Answers to Review Questions 29 Answers to Written Labs 31 Chapter 2 The Open Systems Interconnection Specifications 33 Internetworking Models 34 The Layered Approach 35 Advantages of Reference Models 35 The OSI Reference Model 36 The Application Layer 37 The Presentation Layer 39 The Session Layer 39 The Transport Layer 39 The Network Layer 45 The Data Link Layer 48 The Physical Layer 50 27477book.indd 13 2/25/09 1:14:46 PM  xiv Contents Introduction to Encapsulation 51 Summary 52 Exam Essentials 52 Written Lab 53 Review Questions 54 Answers to Review Questions 58 Answers to Written Lab 60 Chapter 3 Networking Topologies, Connectors, and Wiring Standards 61 Physical Media 63 Coaxial Cable 64 Twisted-Pair Cable 66 Fiber-Optic Cable 69 Serial Cables 73 Properties of Cables 75 Transmission Speeds 75 Distance 76 Duplex 76 Noise Immunity (Security, EMI) 76 Frequency 77 Wiring Standards 77 568A vs. 568B 77 Straight-Through Cable 78 Crossover Cable 78 Rollover Cable 79 Hardware Loopback 80 Installing Wiring Distributions 82 Vertical and Horizontal Cross-Connects 82 Patch Panels 83 Verifying Correct Wiring Installation 86 Verifying Proper Wiring Termination 86 Summary 87 Exam Essentials 87 Written Lab 88 Review Questions 89 Answers to Review Questions 93 Answers to Written Lab 95 Chapter 4 The Current Ethernet Specifications 97 Network Basics 98 Ethernet Basics 100 Collision Domain 100 Broadcast Domain 100 27477book.indd 14 2/25/09 1:14:46 PM  Contents xv CSMA/CD 101 Half- and Full-Duplex Ethernet 102 Ethernet at the Data Link Layer 104 Binary to Decimal and Hexadecimal Conversion 104 Ethernet Addressing 108 Ethernet Frames 108 Channel Bonding 111 Ethernet at the Physical Layer 111 Summary 116 Exam Essentials 116 Written Lab 118 Review Questions 121 Answers to Review Questions 125 Answers to Written Lab 127 Chapter 5 Networking Devices 131 Common Network Connectivity Devices 132 Hub 133 Repeater 134 Modem 134 Network Interface Card (NIC) 136 Transceiver (Media Converter) 137 Bridge 139 Switch 140 Wireless Access Point (AP) 141 Router 142 Firewall 143 Dynamic Host Configuration Protocol (DHCP) Server 144 Other Specialized Devices 147 Multilayer Switch 147 Content Switch 148 Intrusion Detection or Prevention System (IDS/IPS) 148 Load Balancer 149 Multifunction Network Devices 149 Domain Name Service (DNS) Server 149 Bandwidth Shaper 154 Proxy Server 155 Channel Service Unit/Data Service Unit (CSU/DSU) 156 Network Segmentation 157 Switches and Bridges at the Data Link Layer 163 Hubs at the Physical Layer 165 Summary 166 Exam Essentials 166 Written Lab 168 27477book.indd 15 2/25/09 1:14:46 PM  xvi Contents Review Questions 169 Answers to Review Questions 173 Answers to Written Lab 175 Chapter 6 Introduction to Internet Protocol (IP) 177 Introducing TCP/IP 179 A Brief History of TCP/IP 179 TCP/IP and the DoD Model 180 The Process/Application Layer Protocols 182 The Host-to-Host Layer Protocols 190 The Internet Layer Protocols 195 Data Encapsulation 200 Summary 204 Exam Essentials 205 Written Lab 206 Review Questions 207 Answers to Review Questions 211 Answers to Written Lab 213 Chapter 7 IP Addressing 215 IP Terminology 216 The Hierarchical IP Addressing Scheme 217 Network Addressing 218 Private IP Addresses 222 Broadcast Addresses 223 Internet Protocol Version 6 (IPv6) 225 Why Do We Need IPv6? 225 The Benefits of and Uses for IPv6 226 IPv6 Addressing and Expressions 227 Shortened Expression 228 Address Types 229 Special Addresses 230 Summary 230 Exam Essentials 231 Written Lab 232 Review Questions 233 Answers to Review Questions 237 Answers to Written Lab 239 Chapter 8 IP Subnetting, Troubleshooting IP, and Introduction to NAT 241 Subnetting Basics 242 How to Create Subnets 243 Subnet Masks 244 27477book.indd 16 2/25/09 1:14:47 PM  Contents xvii Classless Inter-Domain Routing (CIDR) 245 Subnetting Class C Addresses 247 Subnetting Class B Addresses 256 Troubleshooting IP Addressing 264 Determining IP Address Problems 267 Introduction to Network Address Translation (NAT) 271 Types of Network Address Translation 273 NAT Names 273 How NAT Works 274 Summary 275 Exam Essentials 276 Written Labs 277 Review Questions 278 Answers to Review Questions 283 Answers to Written Labs 285 Chapter 9 Introduction to IP Routing 287 Routing Basics 288 The IP Routing Process 291 Testing Your IP Routing Understanding 297 Static and Dynamic Routing 298 Summary 301 Exam Essentials 301 Written Lab 303 Review Questions 304 Answers to Review Questions 308 Answers to Written Lab 310 Chapter 10 Routing Protocols 311 Routing Protocol Basics 312 Administrative Distances 313 Classes of Routing Protocols 315 Distance-Vector Routing Protocols 316 Routing Information Protocol (RIP) 317 RIP Version 2 (RIPv2) 318 VLSM and Discontiguous Networks 319 EIGRP 321 Border Gateway Protocol (BGP) 323 Link-State Routing Protocols 324 Open Shortest Path First (OSPF) 325 Intermediate System to Intermediate System (IS-IS) 327 IPv6 Routing Protocols 328 RIPng 329 EIGRPv6 329 OSPFv3 329 27477book.indd 17 2/25/09 1:14:47 PM  xviii Contents Summary 330 Exam Essentials 330 Written Lab 331 Review Questions 332 Answers to Review Questions 336 Answers to Written Lab 338 Chapter 11 Switching and Virtual LANs (VLANs) 339 Networking Before Layer 2 Switching 340 Switching Services 344 Limitations of Layer 2 Switching 345 Bridging vs. LAN Switching 345 Three Switch Functions at Layer 2 346 Spanning Tree Protocol (STP) 351 Spanning-Tree Port States 352 STP Convergence 353 Virtual LANs (VLANs) 354 VLAN Basics 354 VLAN Memberships 358 Static VLANs 358 Dynamic VLANs 359 Identifying VLANs 359 VLAN Identification Methods 360 Switching and Network Security 362 Port Security/Authentication 362 How VLANs Enhance Network Security 362 Two Additional Advanced Features of Switches 363 Power over Ethernet (PoE) 364 Port Mirroring/Spanning 366 Summary 367 Exam Essentials 368 Written Lab 369 Review Questions 370 Answers to Review Questions 374 Answers to Written Lab 376 Chapter 12 Wireless Technologies 377 Introduction to Wireless Technology 378 The 802.11 Standards 381 2.4GHz (802.11b) 382 2.4GHz (802.11g) 383 5GHz (802.11a) 384 5GHz (802.11h) 385 2.4GHz/5GHz (802.11n) 385 27477book.indd 18 2/25/09 1:14:47 PM  Contents xix Comparing 802.11 Standards 387 Wireless LAN Modulation Techniques 387 Range Comparisons 388 Wireless Network Components 389 Wireless Access Points 389 Wireless Network Interface Card (NIC) 390 Wireless Antennas 391 Installing a Wireless Network 393 Ad hoc Mode: Independent Basic Service Set (IBSS) 393 Infrastructure Mode: Basic Service Set (BSS) 394 Design Considerations with Large Wireless Networks 396 Installing and Configuring Hardware 398 Wireless Security 406 Open Access 407 Service Set Identifiers (SSIDs), Wired Equivalent Privacy (WEP), and Media Access Control (MAC) Address Authentication 407 Remote Authentication Dial In User Service (RADIUS) 408 Temporal Key Integrity Protocol (TKIP) 409 Wi-Fi Protected Access (WPA) or WPA 2 Pre-Shared Key 410 Summary 412 Exam Essentials 412 Written Lab 414 Review Questions 415 Answers to Review Questions 419 Answers to Written Lab 421 Chapter 13 Authentication and Access Control 423 Security Filtering 425 Access Control Lists 426 Tunneling 427 Encryption 432 Remote Access 436 Managing User Account and Password Security 439 Network Resource-Sharing Security Models 439 Managing User Accounts 440 Managing Passwords 443 User-Authentication Methods 447 Public Key Infrastructure (PKI) 447 Kerberos 448 Authentication, Authorization, and Accounting (AAA) 449 Network Access Control (NAC) 451 Challenge Handshake Authentication Protocol (CHAP) 451 27477book.indd 19 2/25/09 1:14:47 PM  xx Contents MS-CHAP 452 Extensible Authentication Protocol (EAP) 452 Summary 453 Exam Essentials 453 Written Lab 454 Review Questions 455 Answers to Review Questions 459 Answers to Written Lab 461 Chapter 14 Network Threats and Mitigation 463 Recognizing Security Threats 464 Denial of Service (DoS) 465 Viruses 468 Worms 471 Attackers and Their Tools 471 Rogue Access Points 474 Social Engineering (Phishing) 475 Understanding Mitigation Techniques 476 Active Detection 476 Passive Detection 476 Proactive Defense 477 Policies and Procedures 477 Security Policies 478 Security Training 483 Patches and Upgrades 484 Updating Antivirus Components 486 Fixing an Infected Computer 488 Summary 488 Exam Essentials 489 Written Lab 490 Review Questions 491 Answers to Review Questions 495 Answers to Written Lab 497 Chapter 15 Physical and Hardware Security 499 Using Hardware and Software Security Devices 500 Defining Firewalls 502 Network-Based Firewalls 503 Host-Based Firewalls 503 Firewall Technologies 503 Access Control Lists (ACL) 504 Demilitarized Zone (DMZ) 506 Protocol Switching 507 27477book.indd 20 2/25/09 1:14:47 PM  Contents xxi Dynamic Packet Filtering 508 Proxy Services 509 Firewalls at the Application Layer vs. the Network Layer 511 Stateful vs. Stateless Network-Layer Firewalls 512 Application-layer Firewalls 513 Scanning Services and Other Firewall Features 514 Content Filtering 515 Signature Identification 515 Zones 516 Intrusion-Detection and -Prevention Systems 518 Network-Based IDS 519 Host-Based IDS 521 VPN Concentrators 522 Understanding Problems Affecting Device Security 523 Physical Security 523 Logical Security Configurations 525 Restricting Local and Remote Access 527 Secure and Unsecure Application Protocols 529 Summary 534 Exam Essentials 534 Written Lab 536 Review Questions 537 Answers to Review Questions 541 Answers to Written Lab 543 Chapter 16 Wide Area Networks 545 What’s a WAN? 547 Defining WAN Terms 547 The Public Switched Telephone Network (PSTN) 548 WAN Connection Types 549 Bandwidth or Speed 551 T-Series Connections 551 The T1 Connection 552 The T3 Connection 553 Transmission Media 553 Wired Connections 554 Wireless Technologies 555 Broadband Services 556 DSL Technology and xDSL 557 Cable Modem 559 WAN Protocols 560 Integrated Services Digital Network (ISDN) 560 Frame Relay Technology 562 27477book.indd 21 2/25/09 1:14:48 PM  xxii Contents Asynchronous Transfer Mode (ATM) 565 Multi Protocol Label Switching (MPLS) 565 Summary 567 Exam Essentials 567 Written Lab 568 Review Questions 569 Answers to Review Questions 572 Answers to Written Lab 574 Chapter 17 Command-Line Tools 575 Using Traceroute 577 Using ipconfig and ifconfig 578 Using the ipconfig Utility 578 Using the ifconfig Utility 582 Using the ping Utility 583 Using the Address Resolution Protocol (ARP) 586 The Windows ARP Table 586 Using the arp Utility 587 Using the nslookup Utility 590 Resolving Names with the Hosts Table 592 Using the Mtr Command 593 Using the Route Command 594 Using the route Command Options 595 Some Examples of the route Command 597 Using the nbtstat Utility 597 The –a Switch 598 The –A Switch 600 The –c Switch 600 The –n Switch 601 The –r Switch 601 The –R Switch 602 The –S Switch 602 The –s Switch 603 Using the netstat Utility 603 The –a Switch 606 The –e Switch 607 The –r Switch 608 The –s Switch 608 The –p Switch 608 The –n Switch 610 Using the File Transfer Protocol (FTP) 612 Starting FTP and Logging In to an FTP Server 613 Downloading Files 614 Uploading Files 616 27477book.indd 22 2/25/09 1:14:48 PM  Contents xxiii Using the Telephone Network (Telnet) Utility 617 How to Enable Telnet in Vista 617 Don’t Use Telnet, Use Secure Shell (SSH) 618 Summary 619 Exam Essentials 619 Written Lab 620 Review Questions 621 Answers to Review Questions 626 Answers to Written Lab 628 Chapter 18 Software and Hardware Tools 629 Understanding Network Scanners 630 Packet Sniffers 630 Intrusion Detection and Prevention Software (IDS/IPS) 632 Port Scanners 634 Identifying Hardware Tools 637 Cable Testers 637 Protocol Analyzer 639 Certifiers 640 Time-Domain Reflectometer (TDR) 640 Optical Time-Domain Reflectometer (OTDR) 641 Multimeter 642 Toner Probe 642 Butt Set 644 Punch-Down Tool 644 Cable Stripper/Snips 646 Voltage Event Recorder 647 Temperature Monitor 648 Summary 649 Exam Essentials 649 Written Lab 650 Review Questions 651 Answers to Review Questions 655 Answers to Written Lab 657 Chapter 19 Network Troubleshooting 659 Narrowing Down the Problem 661 Are There Any Cabling Issues? Did You Check the Super Simple Stuff? 662 Is Hardware or Software Causing the Problem? 665 Is It a Workstation or a Server Problem? 666 Which Segments of the Network Are Affected? 667 Is It Bad Cabling? 667 27477book.indd 23 2/25/09 1:14:48 PM  xxiv Contents Troubleshooting Steps 672 Step 1: Information Gathering—Identify Symptoms and Problems 672 Step 2: Identify the Affected Areas of the Network 673 Step 3: Determine if Anything Has Changed 674 Step 4: Establish the Most Probable Cause 675 Step 5: Determine if Escalation Is Necessary 678 Step 6: Create an Action Plan and Solution, Identifying Potential Effects 680 Step 7: Implement and Test the Solution 683 Step 8: Identify the Results and Effects of the Solution 683 Step 9: Document the Solution and the Entire Process 684 Troubleshooting Tips 685 Don’t Overlook the Small Stuff 685 Prioritize Your Problems 685 Check the Software Configuration 686 Don’t Overlook Physical Conditions 686 Don’t Overlook Cable Problems 687 Check for Viruses 687 Summary 688 Exam Essentials 688 Written Lab 690 Review Questions 691 Answers to Review Questions 695 Answers to Written Lab 697 Chapter 20 Management, Monitoring, and Optimization 699 Managing Network Documentation 702 Schematics and Diagrams 703 Baselines 709 Policies, Procedures, and Regulations 711 Monitoring the Network and Optimizing Its Performance 713 Network Monitoring and Logging 713 Reasons to Optimize Your Network’s Performance 716 How to Optimize Performance 718 Summary 721 Exam Essentials 722 Written Lab 723 Review Questions 724 Answers to Review Questions 728 Answers to Written Lab 730 27477book.indd 24 2/25/09 1:14:48 PM  Contents xxv Appendix A Subnetting Class A 731 Subnetting Practice Examples: Class A Addresses 732 Practice Example #1A: 255.255.0.0 (/16) 733 Practice Example #2A: 255.255.240.0 (/20) 733 Practice Example #3A: 255.255.255.192 (/26) 734 Subnetting in Your Head: Class A Addresses 734 Written Lab 1 736 Written Lab 2 737 Answers to Written Lab 1 738 Answers to Written Lab 2 739 Appendix B About the Companion CD 741 What You’ll Find on the CD 742 Sybex Test Engine 742 PDF of the Book 742 Adobe Reader 742 Electronic Flashcards 743 System Requirements 743 Using the CD 743 Troubleshooting 743 Customer Care 744 Glossary 745 Index 791 27477book.indd 25 2/25/09 1:14:48 PM 27477flast.indd 26 2/27/09 6:27:27 AM  Introduction If you’re like most of us in the networking community, you probably have one or more network certifications. If that’s you, you’re very wise in choosing to go for a Network+ cer- tification to proudly add to your repertoire, because that achievement will make you all the more valuable as an employee. And in these challenging economic times, keeping ahead of the competition—even standing out among your present colleagues—could make a big dif- ference in whether you gain a promotion or possibly keep your job instead of being the one who gets laid off! Or maybe this is your first attempt at certification because you’ve decided to venture into a new career in information technology (IT). You’ve realized that getting into the IT sector is a good way to go because as the Information Age marches on, the demand for knowledgeable professionals in this dynamic field will only be intensify dramatically. Either way, certification is one of the best things you can do for your career if you are work- ing in, or want to break into, the networking profession, because it proves that you know what you’re talking about regarding the subjects you’re certified in. It also powerfully endorses you as a professional in a way that’s very similar to a physician being “board certified” in a certain area of expertise. In this book, you’ll find out what the Network+ exam is all about, because each chapter covers a part of the exam. I’ve included some great review questions at the end of each chapter to help crystallize the information you learned and solidly prepare you to ace the exam. A really cool thing about working in IT is that it’s constantly evolving so there are always new things to learn and fresh challenges to master. Once you obtain your Network+ certification and discover that you’re interested in taking it further by getting into more complex networking (and make more money), the Cisco CCNA certification is definitely your next step; you can get the skinny on that and even more in-depth certifications on my blog at www.lammle.com. What Is the Network+ Certification? Network+ is a certification developed by the Computing Technology Industry Association (CompTIA) that exists to provide resources and education for the computer and technology community. This is the same body that developed the A+ exam for computer technicians. Way back in 1995, members of the organization got together to develop a new certification that tests skills for IT. To ensure industry-wide support, it was sponsored by many past and present IT industry leaders like these: NN Compaq Computers NN Digital Equipment Corporation (a part of Compaq) NN IBM NN Lotus 27477flast.indd 27 2/27/09 6:27:28 AM  xxviii Introduction NN Microsoft NN Novell NN TSS NN U.S. Robotics NN US West NN Wave Technologies The Network+ exam was designed to test the skills of network technicians with 18 to 24 months of experience in the field. It tests areas of networking technologies such as the defini- tion of a protocol, the Open Systems Interconnect (OSI) model and its layers, and the con- cepts of network design and implementation—the minimum knowledge required for working on a network and some integral prerequisites for network design and implementation. Why Become Network+ Certified? The Network+ certification is a relatively new certification, and it’s the next certification in the lineup of CompTIA certifications beginning with the A+ certification. Because CompTIA is a well-respected developer of vendor-neutral industry certifications, becoming Network+ certified proves you’re competent in the specific areas tested by Network+. Three major benefits are associated with becoming Network+ certified: NN Proof of professional achievement NN Opportunity for advancement NN Fulfillment of training requirements Proof of Professional Achievement Networking professionals are pretty competitive when it comes to collecting more certifica- tions than their peers. And because the Network+ certification broadly covers the entire field of networking, technicians want this certification a lot more than having just Microsoft certs—Net+ is a lot more prestigious and valuable. Because it’s rare to gain something that’s worth a lot with little effort, I’ll be honest—preparing for the Network+ exam isn’t exactly a lazy day at the beach. (However, beaches do happen to be really high on my personal list of great places to study!) And people in IT know that it isn’t all that easy to pass the Net+ exam, so they’ll definitely respect you more and know that you’ve achieved a certain level of expertise about vendor-independent networking-related subjects. Opportunity for Advancement We all like to get ahead in our careers—advancement results in more responsibility and prestige, and it usually means a fatter paycheck, greater opportunities, and added options. 27477flast.indd 28 2/27/09 6:27:29 AM  Introduction xxix In the IT sector, a great way to make sure all that good stuff happens is by earning a lot of technology certifications, including Network+. Network+, because of its wide-reaching industry support, is recognized as a baseline of networking information. Some companies actually specify the possession of both Network+ and A+ certifications as job requirements before they’ll even consider hiring you, or maybe before your next review. And often, gaining a Network+ certification will get you a pay raise at review time. How to Become Network+ Certified The simplest way to become Network+ certified is to take the exam. It is administered by Pearson VUE and Thomson Prometric, which you’re already familiar with if you’ve taken other computer certification exams. If you haven’t, surprise—the test is adminis- tered by a computer. The test is 90 minutes long, with 100 questions. That is less than one minute per question, but as of the time of this writing, all question are multiple choice, so that makes it somewhat of an easier test then a test with simulations and drag and drop questions. Also to your ben- efit, you can review your answers before you finish your test, which gives you a review period if you finish before 90 minutes. You need to get a score of 720 out of 1000 To register to take the exam, call Thomson Prometric (not the testing center) at 888-895-6116 or Pearson VUE at 877-551-PLUS. Be prepared to pay for the exam at registration time with a major credit card like Visa or MasterCard. Check CompTIA’s website, because prices may vary. This book covers everything about CompTIA Network+. For up-to-date infor- mation about Todd Lammle CompTIA bootcamps, audio training, and train- ing videos, please see www.lammle.com and/or www.globalnettraining.com. You can take the CompTIA exam at any of the more than 800 Prometric Authorized Testing Centers around the world (www.2test.com), or call 800-204-EXAM (3926). You can also register and take the exams at a Pearson VUE authorized center (www.vue.com) or call (877) 404-EXAM (3926). To register for a CompTIA exam, do the following: 1. Determine the number of the exam you want to take—the CompTIA Network+ exam number is N10-004. 2. Register with the nearest Prometric Registration Center or Pearson VUE testing center. Like I said, you have to pay for the exam in advance; at this writing, the exam costs $239 and must be taken within one year of payment. You can schedule an exam up to six weeks in advance or as late as the same day you want to take it. If something comes up and you need to cancel or reschedule your exam appointment, contact Prometric or Pearson VUE at least 24 hours in advance. 27477flast.indd 29 2/27/09 6:27:29 AM  xxx Introduction 3. When you schedule the exam, you’ll get instructions regarding all appointment and cancellation procedures, the ID requirements, and information about the testing-center location. At the end of the exam, your score report will be displayed on the screen and printed out so that you have a hard copy. Who Should Buy This Book? You—if want to pass the Network+ exam, and pass it confidently, that is! This book is chock full of the exact information you need that directly maps to Net+ exam objectives; so if you use it to study for the exam, your odds of passing shoot way up. And in addition to including every bit of knowledge you need to learn to pass the exam, I’ve also included some really great tips and solid wisdom to equip you even fur- ther to successfully work in the real IT world. What Does This Book Cover? This book covers everything you need to know in order to pass the CompTIA Network+ (N10-004) exam. But in addition to studying the book, it’s a good idea to practice on an actual network if you can. Here’s a list of the 20 chapters in this book. At the end each of them, I’ve included a written lab and some key review questions to help you hone your skills: Chapter 1, Introduction to Networks ​ ​An introduction to what a network is, and an overview of the most common physical network topologies you’ll find in today’s networks. Chapter 2, The Open Systems Interconnection Specifications ​ ​This chapter covers the OSI model, what it is, what happens at each of its layers, and how each layer works. Chapter 3, Networking Topologies, Connectors, and Wiring Standards ​ ​This chapter covers the various networking media and topologies, plus the cable types and properties used in today’s networks. Chapter 4, The Current Ethernet Specifications ​ ​This chapter covers how a basic Ethernet LAN works, and describes and categorizes the different Ethernet specifications. Chapter 5, Networking Devices ​ ​It’s important for you to understand all the various devices used in today’s networks, and this chapter will describe how hubs, routers, and switches and some other devices work within a network. Chapter 6, Introduction to Internet Protocol (IP) ​ ​This is your introduction to the all- important IP protocol stack. 27477flast.indd 30 2/27/09 6:27:29 AM  Introduction xxxi Chapter 7, IP Addressing ​ ​This chapter will take up from where Chapter 6 left off and move into IP addressing. It also contains information about public versus private addressing and DHCP. Chapter 8, IP Subnetting, Troubleshooting IP, And Introduction to NAT ​ ​Beginning where Chapter 7 ends, we’ll be tackling IP subnetting in this one. But no worries here— I’ve worked hard to make this not-so-popular yet vital topic as painless as possible. Chapter 9, Introduction to IP Routing ​ ​This is an introduction to routing that basically covers what routers do and how they do it. This chapter, along with Chapters 10 and 11, cover routing and switching in much more detail than what is necessary to meet the CompTIA Network+ objectives, because this knowledge is so critical to grasp when working with today’s networks. Chapter 10, Routing Protocols ​ ​This chapter goes into detail describing the protocols that run on routers and that update routing tables to create a working map of the network. Chapter 11, Switching and Virtual LANs (VLANs) ​ ​This chapter covers Layer 2 switching, the Spanning Tree Protocol (STP), and Virtual LANs. Just as I went in deeper than needed for the exam with the routing chapters, I’ll cover switching and virtual LANs (which are also vital in today’s corporate networks) more thoroughly as well. Chapter 12, Wireless Technologies ​ ​Because wireless is so important for both home and business networks today, this chapter is loaded with all the information you need to be successful at wireless networking at home and work. Chapter 13, Authentication and Access Control ​ ​This is the first of three security chapters. There are tons of exam objectives about network security that are so important that I took three chapters to cover all of them. In this chapter, I’ll introduce security, security filtering, tunneling, and user authentication. Chapter 14, Network Threats and Mitigation ​ ​This is probably the most fun of the three security chapters because I’ll tell you all about security threats and how to stop them. The only way to get good at network security is to implement it, and this chapter shows you how. Chapter 15, Physical and Hardware Security ​ ​This chapter’s focus is on explaining basic firewalls, security devices, and device security. Chapter 16, Wide Area Networks ​ ​In this chapter, you get to learn all about things like frame relay, E1/T1, DSL, cable modems, and more. All the CompTIA Network+ WAN objectives are covered in this chapter. Chapter 17, Command-Line Tools ​ ​This is also a fun chapter because again, you can follow along and run all the commands yourself. And I repeat, it’s a really good idea to do that! Chapter 18, Software and Hardware Tools ​ ​This chapter introduces you to the network tools you will use to help you run your networks. Both software and hardware tools will be discussed. 27477flast.indd 31 2/27/09 6:27:29 AM  xxxii Introduction Chapter 19, Network Troubleshooting ​ ​In almost every chapter, I discuss how to verify and fix problems, but this chapter will get really into the nuts and bolts of detailed network troubleshooting and documentation. Chapter 20, Management, Monitoring, and Optimization ​ ​This last chapter will provide configuration-management documentation and covers wiring, logical diagrams, baselines, policies, and regulations. How to Use This Book If you want a solid foundation for the serious effort of preparing for the CompTIA Network+ (N10-004) exam, then look no further, because I’ve spent countless hours putting together this book with the sole intention of helping you to pass the Network+ exam! This book is loaded with valuable information, and you will get the most out of your study time if you understand how I put the book together. Here’s a list that describes how to approach studying so you get the most out of it: 1. Take the assessment test immediately following this introduction. (The answers are at the end of the test, but no peeking!) It’s okay if you don’t know any of the answers— that’s what this book is for. Carefully read over the explanations for any question you get wrong, and make note of the chapters where that material is covered. 2. Study each chapter carefully, making sure that you fully understand the information and the test objectives listed at the beginning of each one. Again, pay extra-close attention to any chapter that includes material covered in questions you missed on the assessment test. 3. Complete the Written Lab at the end of each chapter. Do not skip these written exercises, because they directly map to the CompTIA objectives and what you’ve got to have nailed down to meet them. 4. Answer all the Review Questions related to each chapter. (The answers appear at the end of the chapters—no cheating!) Specifically note any questions that confuse you, and study those sections of the book again. And don’t just skim these questions—make sure you understand each answer completely. 5. Try your hand at the bonus exams included on the companion CD. The questions in these exams appear only on the CD. Check out www.lammle.com for more CompTIA Network+ exam prep questions. The questions found at www.lammle.com will be updated at least monthly, maybe weekly or even daily. Before you take your test, be sure and visit my website for questions, videos, audios, and other useful information. 6. Test yourself using all the flashcards on the CD. These are brand-new and updated flashcard programs to help you prepare for the latest CompTIA Network+ exam, and they’re really great study tools. 27477flast.indd 32 2/27/09 6:27:30 AM  Introduction xxxiii I tell you no lies—learning every bit of the material in this book is going to require apply- ing yourself with a good measure of discipline. So try to set aside the same time period every day to study, and select a comfortable and quiet place to do so. If you work hard, you will be surprised at how quickly you learn this material. If you follow the steps listed here, study, and practice the Review Questions, bonus exams, electronic flashcards, and all t