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CompTIA Network+ N10-005 Exam Cram, 4th Edition

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CompTIA Network+ N10-005 Exam Cram, 4th Edition

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  • Copyright 2012
  • Edition: 4th
  • Book
  • ISBN-10: 0-7897-4905-X
  • ISBN-13: 978-0-7897-4905-5

Prepare for CompTIA Network+ N10-005 exam success with this CompTIA Authorized Exam Cram from Pearson IT Certification, a leader in IT Certification learning and a CompTIA Authorized Platinum Partner.

Limited Time Offer: Buy CompTIA Network+ N10-005 Authorized Exam Cram and receive a 10% off discount code for the CompTIA Network+ N10-005 exam.  To receive your 10% off discount code:

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CompTIA® Network+ N10-005 Authorized Exam Cram, Fourth Edition is the perfect study guide to help you pass CompTIA’s new Network+ N10-005 exam. It provides coverage and practice questions for every exam topic, including substantial new coverage of security, wireless, and voice networking. The book contains an extensive set of preparation tools, such as quizzes, Exam Alerts, and a practice exam, while the CD’s state-of-the-art test engine provides real-time practice and feedback.

Covers the critical information you’ll need to know to score higher on your Network+ (N10-005) exam!

  • Understand modern network topologies, protocols, and models
  • Work effectively with DNS and DHCP
  • Monitor and analyze network traffic
  • Understand IP addressing, routing, and switching
  • Perform basic router/switch installation and configuration
  • Manage networks and utilize basic optimization techniques
  • Plan and implement a small office/home office network
  • Master essential LAN, WAN, and wireless technologies
  • Install, configure, secure, and troubleshoot wireless networks
  • Safeguard networks with VPNs, authentication, firewalls, and security appliances
  • Troubleshoot common problems with routers, switches, and physical connectivity

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 and two complete practice exams. 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 Certifcation Practice Test Minimum System Requirements

  • Windows XP (SP3), WIndows Vista (SP2), or Windows 7
  • Microsoft .NET Framework 4.0 Client
  • Pentium-class 1 GHz processor (or equivalent)
  • 512 MB RAM
  • 650 MB disk space plus 50 MB for each downloaded practice exam


EMMETT DULANEY (Network+, A+, Security+) is a columnist for CertCites, an associate professor at Anderson University, and the author of numerous certification guides including CompTIA A+ Complete Study Guide and CompTIA Security+ Study Guide.

MICHAEL HARWOOD (MCSE, A+, Network+, Server+, Linux+) has more than 14 years of IT experience in roles including network administrator, instructor, technical writer, website designer, consultant, and online marketing strategist. He regularly discusses technology topics on Canada’s CBC Radio.

Premium Edition

Limited Time Offer: Buy CompTIA Network+ N10-005 Exam Cram, Premium Edition eBook and Practice Test and receive a 10% off discount code for the CompTIA Network+ N10-005 exam.  To receive your 10% off discount code visit your pearsonITcertification.com Account page, locate the product and click on “Access Bonus Content”.


The exciting new CompTIA Network+ N10-005 Exam Cram, Premium Edition eBook and Practice Test is a digital-only certification preparation product combining an eBook with enhanced Pearson IT Certification Practice Test.  The Premium Edition eBook and Practice Test contains the following items:
  • The Network+ N10-005 Premium Edition Practice Test, including four full practice exams and enhanced practice test features
  • PDF and EPUB formats of the CompTIA Network+ N10-005 Exam Cram from Pearson IT Certification, which are accessible via your PC, tablet, and Smartphone

About the Premium Edition Practice Test

This Premium Edition contains an enhanced version of the Pearson IT Certification Practice Test (PCPT) software with three full practice exams. In addition, it contains all the chapter-opening assessment questions from the book. This integrated learning package:

  • Allows you to focus on individual topic areas or take complete, timed exams
  • Includes direct links from each question to detailed tutorials to help you understand the concepts behind the questions
  • Provides unique sets of exam-realistic practice questions
  • Tracks your performance and provides feedback on a module-by-module basis, 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), or Windows 7;

Microsoft .NET Framework 4.0 Client;

Pentium class 1GHz processor (or equivalent);

512 MB RAM;

650 MB disc space plus 50 MB for each downloaded practice exam

About the Premium Edition eBook

CompTIA Netwrok+ N10-005 Exam Cram is a best-of-breed exam study guide. Best-selling authors Dulaney and Harwood share preparation hints and test-taking tips, helping you identify areas of weakness and improve both your conceptual knowledge and hands-on skills. Material is presented in a concise manner, focusing on increasing your understanding and retention of exam topics.

CompTIA Network+ N10-005 Exam Cram presents you with an organized test preparation routine through the use of proven series elements and techniques. Exam topic lists make referencing easy. Exam Alerts, Sidebars, and Notes interspersed throughout the text keep you focused on what you need to know. Cram Quizzes help you assess your knowledge, and the Cram Sheet tearcard is the perfect last minute review.

Well-regarded for its late stage review, assessment features, and challenging review questions and exercises, this approved study guide helps you master the concepts and techniques that will enable you to succeed on the exam the first time.

The approved study guide helps you master all the topics on the Network+ exam, including:

  • Computer networks and the OSI model
  • Network components
  • Ethernet
  • IP addressing
  • Routing traffic
  • Wide Area Networks (WANs)
  • Wireless LANs
  • Network performance
  • Command-line utilities
  • Network management
  • Network security
  • Troubleshooting
Emmett Dulaney  is author of 40+ books on certification and security, including Security+ Study Guide, 5th Edition and i-Net+ Exam Cram. He is certification columnist for CertCities and an associate professor at Anderson University. He has held certifications from almost every vendor including CompTIA (A+, Network+, Security+), Microsoft, Novell, Cisco, IBM, LPI, and many others. He co-founded Mercury Technical Solutions. Michael Harwood (MCSE, A+, Network+, Server+, Linux+) has authored or co-authored three best-selling books on Network+. He is system manager for a multi-site network, and consults for a major networking firm.

Sample Content

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Network+ Exam Cram: Addressing and Routing

Sample Pages

Download the sample pages (includes Chapter 3 and Index)

Table of Contents

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

About Network+ Exam Cram. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

About the Network+ Exam . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

CompTIA Network+ Exam Topics . . . . . . . . . . . . . . . . . . . . . . 2

Booking and Taking the Network+ Certification Exam . . . . . . . . . 4

What to Expect from the Exam . . . . . . . . . . . . . . . . . . . . . . . . 5

A Few Exam Day Details. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

After the Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Last-Minute Exam Tips . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

CHAPTER 1:

Introduction to Networking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

LANs, WANs, and Network Models . . . . . . . . . . . . . . . . . . . . . . . . 10

LANs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

WANs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Network Models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Centralized Computing versus Distributed Computing . . . . . . . . 14

Cram Quiz Answers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

Network Topologies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

Bus Topology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

Ring Topology. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

Star Topology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

Mesh Topology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

Wireless Topologies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

Point-to-Point, Point-to-Multipoint, and Wireless Mesh

Topologies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

Hybrid Topologies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

Cram Quiz Answers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

Going Virtual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

Virtual Private Networks (VPNs) . . . . . . . . . . . . . . . . . . . . . . 32

Virtual Local Area Networks (VLANs) . . . . . . . . . . . . . . . . . . . 35

Cram Quiz Answers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

What Next? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41

CHAPTER 2:

OSI and TCP/IP Models and Network Protocols . . . . . . . . . . . . . . . . . . . 43

The Networking Models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44

The OSI Seven-Layer Model . . . . . . . . . . . . . . . . . . . . . . . . . 44

The TCP/IP Four-Layer Model . . . . . . . . . . . . . . . . . . . . . . . 49

Identifying the OSI Layers at Which Various Network

Components Operate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50

Cram Quiz Answers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51

Protocols . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53

Connection-Oriented Protocols Versus Connectionless Protocols ......54

Internet Protocol (IP) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55

Transmission Control Protocol (TCP) . . . . . . . . . . . . . . . . . . . 55

User Datagram Protocol (UDP) . . . . . . . . . . . . . . . . . . . . . . . 56

File Transfer Protocol (FTP) . . . . . . . . . . . . . . . . . . . . . . . . . 57

Secure File Transfer Protocol (SFTP). . . . . . . . . . . . . . . . . . . . 58

Trivial File Transfer Protocol (TFTP) . . . . . . . . . . . . . . . . . . . 59

Simple Mail Transfer Protocol (SMTP) . . . . . . . . . . . . . . . . . . 59

Hypertext Transfer Protocol (HTTP) . . . . . . . . . . . . . . . . . . . 60

Hypertext Transfer Protocol Secure (HTTPS) . . . . . . . . . . . . . . 60

Post Office Protocol Version 3/Internet Message Access Protocol

Version 4 (POP3/IMAP4) . . . . . . . . . . . . . . . . . . . . . . . . . . 61

Telnet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62

Secure Shell (SSH) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62

Internet Control Message Protocol (ICMP). . . . . . . . . . . . . . . . 63

Address Resolution Protocol (ARP)/Reverse Address Resolution

Protocol (RARP) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63

Network Time Protocol (NTP) . . . . . . . . . . . . . . . . . . . . . . . 65

Network News Transfer Protocol (NNTP) . . . . . . . . . . . . . . . . 66

Secure Copy Protocol (SCP) . . . . . . . . . . . . . . . . . . . . . . . . . 66

Lightweight Directory Access Protocol (LDAP) . . . . . . . . . . . . . 66

Internet Group Management Protocol (IGMP) . . . . . . . . . . . . . 67

Transport Layer Security . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67

Session Initiation Protocol (SIP)/Real-Time Transport

Protocol (RTP) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68

TCP/IP Protocol Suite Summary . . . . . . . . . . . . . . . . . . . . . . 69

Cram Quiz Answers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73

Domain Name Service (DNS) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74

The DNS Namespace . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76

Types of DNS Entries. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78

DNS Records . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78

CompTIA Network+ N10-005 Authorized Exam Cram

DNS in a Practical Implementation . . . . . . . . . . . . . . . . . . . . . 79

Cram Quiz Answers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81

Simple Network Management Protocol (SNMP) . . . . . . . . . . . . . . . . 82

Components of SNMP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83

SNMP Management Systems . . . . . . . . . . . . . . . . . . . . . . . . . 83

SNMP Agents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84

Management Information Bases (MIBs) . . . . . . . . . . . . . . . . . . 85

SNMP Communities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85

SNMPv3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86

Cram Quiz Answers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87

Dynamic Host Configuration Protocol (DHCP) . . . . . . . . . . . . . . . . 88

The DHCP Process . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89

DHCP and DNS Suffixes . . . . . . . . . . . . . . . . . . . . . . . . . . . 90

Cram Quiz Answers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91

What Next? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92

CHAPTER 3:

Addressing and Routing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93

IP Addressing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94

IPv4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95

IP Address Classes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95

Subnet Mask Assignment . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96

Subnetting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97

Identifying the Differences Between IPv4 Public and Private

Networks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98

Classless Interdomain Routing (CIDR) . . . . . . . . . . . . . . . . . . 100

Default Gateways . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100

IPv4 Address Types. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102

IPv6 Addressing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102

Comparing IPv4 and IPv6 Addressing. . . . . . . . . . . . . . . . . . . 106

Assigning IP Addresses . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107

Identifying MAC Addresses . . . . . . . . . . . . . . . . . . . . . . . . . 110

Network Address Translation (NAT) and Port Address

Translation (PAT) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 112

Cram Quiz Answers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116

Understanding TCP/UDP Port Functions . . . . . . . . . . . . . . . . . . . 117

Cram Quiz Answers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119

Managing TCP/IP Routing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120

The Default Gateway . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120

Routing Tables. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121

Static Routing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122

Dynamic Routing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123

Routing Metrics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 127

Cram Quiz Answers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128

Configuring Routers and Switches . . . . . . . . . . . . . . . . . . . . . . . . . 129

Power over Ethernet (PoE). . . . . . . . . . . . . . . . . . . . . . . . . . 129

The Spanning Tree Protocol (STP) . . . . . . . . . . . . . . . . . . . . 130

Trunking. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131

Port Mirroring. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132

Port Authentication. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132

Cram Quiz Answers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133

What Next? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 134

CHAPTER 4:

Components and Devices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135

Common Network Devices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 136

Bridges. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 136

DHCP Server . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 138

Firewalls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139

Hubs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 140

Media Converters. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141

Modems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 142

Network Cards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 142

Routers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145

Switches . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 146

Wireless Access Points. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 149

Encryption Devices. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 150

Cram Quiz Answers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 152

Specialized Network Devices . . . . . . . . . . . . . . . . . . . . . . . . . . . . 153

Bandwidth Shaper. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 154

Content Filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 155

Load Balancer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 155

Multilayer and Content Switches . . . . . . . . . . . . . . . . . . . . . . 155

Proxy Server . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 156

VPN Concentrator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 158

Network Devices Summary . . . . . . . . . . . . . . . . . . . . . . . . . 159

Cram Quiz Answers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 161

Virtual Network Components. . . . . . . . . . . . . . . . . . . . . . . . . . . . 162

Virtual Desktops. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 162

Virtual Servers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 163

Virtual Switches . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 163

Virtual PBX. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 164

Onsite Versus Offsite. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 164

Network as a Service (NaaS) . . . . . . . . . . . . . . . . . . . . . . . . . 165

Cram Quiz Answers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 166

What Next? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 166

CHAPTER 5:

Installation and Configuration. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 167

Creating a SOHO Network . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 168

Cram Quiz Answers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 174

WAN Technologies. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 175

Switching Methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 175

Integrated Services Digital Network (ISDN) . . . . . . . . . . . . . . 178

T-carrier Lines. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 180

SONET/OCx Levels. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 182

X.25 and Frame Relay . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 183

Asynchronous Transfer Mode (ATM) . . . . . . . . . . . . . . . . . . . 186

Summary of WAN Technologies . . . . . . . . . . . . . . . . . . . . . . 187

Cram Quiz Answers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 189

Internet Access Technologies . . . . . . . . . . . . . . . . . . . . . . . . . . . . 191

DSL Internet Access . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 192

Cable Internet Access . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 195

Broadband Security Considerations . . . . . . . . . . . . . . . . . . . . 197

POTS Internet Access . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 198

The Public Switched Telephone Network (PSTN) . . . . . . . . . . 200

Satellite Internet Access . . . . . . . . . . . . . . . . . . . . . . . . . . . . 201

Wireless Internet Access . . . . . . . . . . . . . . . . . . . . . . . . . . . 202

Cellular . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 204

Cram Quiz Answers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 206

What Next? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 207

CHAPTER 6:

Cabling and Wiring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 209

General Media Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . 210

Broadband Versus Baseband Transmissions . . . . . . . . . . . . . . . 211

Simplex, Half Duplex, and Full Duplex Modes . . . . . . . . . . . . . 212

Media Interference . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 212

Attenuation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 213

Data Transmission Rates . . . . . . . . . . . . . . . . . . . . . . . . . . . 213

Types of Network Media . . . . . . . . . . . . . . . . . . . . . . . . . . . 214

Types of Media Connectors . . . . . . . . . . . . . . . . . . . . . . . . . 221

Media Converters. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 226

568A and 568B Wiring Standards . . . . . . . . . . . . . . . . . . . . . 227

Straight-Through Versus Crossover Cables . . . . . . . . . . . . . . . 228

Rollover and Loopback Cables . . . . . . . . . . . . . . . . . . . . . . . 230

Components of Wiring Distribution. . . . . . . . . . . . . . . . . . . . 231

Cram Quiz Answers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 243

Comparing and Contrasting LAN Technologies . . . . . . . . . . . . . . . . 244

IEEE 802.2 Standard. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 245

802.3 Ethernet Standards . . . . . . . . . . . . . . . . . . . . . . . . . . . 249

Cram Quiz Answers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 257

What Next? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 258

CHAPTER 7:

Wireless . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 259

Understanding Wireless Basics . . . . . . . . . . . . . . . . . . . . . . . . . . . 260

Wireless Access Points (APs). . . . . . . . . . . . . . . . . . . . . . . . . 261

Wireless Antennas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 264

Wireless Radio Channels . . . . . . . . . . . . . . . . . . . . . . . . . . . 268

Data Rate Versus Throughput. . . . . . . . . . . . . . . . . . . . . . . . 271

Beacon Management Frame . . . . . . . . . . . . . . . . . . . . . . . . . 272

Spread-Spectrum Technology . . . . . . . . . . . . . . . . . . . . . . . . 273

Orthogonal Frequency Division Multiplexing. . . . . . . . . . . . . . 274

Infrared Wireless Networking. . . . . . . . . . . . . . . . . . . . . . . . 274

Establishing Communications Between Wireless Devices . . . . . . 275

Configuring the Wireless Connection. . . . . . . . . . . . . . . . . . . 278

Cram Quiz Answers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 283

802.11 Wireless Standards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 284

The Magic Behind 802.11n . . . . . . . . . . . . . . . . . . . . . . . . . 285

A Summary of 802.11 Wireless Standards . . . . . . . . . . . . . . . . 286

Cram Quiz Answers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 288

Securing Wireless Networks. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 289

Wired Equivalent Privacy (WEP) . . . . . . . . . . . . . . . . . . . . . 290

Wi-Fi Protected Access (WPA) . . . . . . . . . . . . . . . . . . . . . . . 292

WPA2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 293

WPA Enterprise. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 294

Cram Quiz Answers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 296

Wireless Troubleshooting Checklist . . . . . . . . . . . . . . . . . . . . . . . . 298

Factors Affecting Wireless Signals . . . . . . . . . . . . . . . . . . . . . 300

Cram Quiz Answers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 302

What Next? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 302

CHAPTER 8:

Network Management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 303

Documentation Management . . . . . . . . . . . . . . . . . . . . . . . . . . . . 305

Wiring Schematics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 307

Physical and Logical Network Diagrams . . . . . . . . . . . . . . . . . 310

Baselines. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 313

Policies, Procedures, Configurations, and Regulations . . . . . . . . 314

Cram Quiz Answers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 321

Monitoring Network Performance. . . . . . . . . . . . . . . . . . . . . . . . . 322

Common Reasons to Monitor Networks . . . . . . . . . . . . . . . . . 323

Packet Sniffers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 324

Throughput Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 325

Port Scanners . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 327

Network Performance, Load, and Stress Testing . . . . . . . . . . . . 329

Tracking Event Logs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 331

Cram Quiz Answers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 337

Networking Tools. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 338

Wire Crimpers, Strippers, and Snips. . . . . . . . . . . . . . . . . . . . 339

Voltage Event Recorder . . . . . . . . . . . . . . . . . . . . . . . . . . . . 340

Environmental Monitors . . . . . . . . . . . . . . . . . . . . . . . . . . . 341

Toner Probes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 342

Protocol Analyzer. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 343

Media/Cable Testers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 344

TDR and OTDR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 344

Multimeter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 345

Network Qualification Tester . . . . . . . . . . . . . . . . . . . . . . . . 346

Butt Set . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 346

Wireless Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 347

Cram Quiz Answers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 349

Working with Command-Line Utilities . . . . . . . . . . . . . . . . . . . . . 350

The Trace Route Utility (tracert/traceroute) . . . . . . . . . . . . . . 352

ping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 355

ARP. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 360

The netstat Command. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 363

nbtstat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 369

The ipconfig Command. . . . . . . . . . . . . . . . . . . . . . . . . . . . 370

ifconfig. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 372

nslookup. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 373

dig. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 375

The host Command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 376

The route Utility . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 376

Cram Quiz Answers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 379

What Next? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 380

CHAPTER 9:

Network Optimization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 381

Uptime and Fault Tolerance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 382

Types of Fault Tolerance . . . . . . . . . . . . . . . . . . . . . . . . . . . 384

Link Redundancy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 392

Common Address Redundancy Protocol (CARP) . . . . . . . . . . . 393

Using Uninterruptible Power Supplies (UPSs) . . . . . . . . . . . . . 393

Cram Quiz Answers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 396

Disaster Recovery. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 397

Full Backups . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 398

Differential Backups . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 398

Incremental Backups . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 399

Tape Rotations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 400

Backup Best Practices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 401

Hot and Cold Spares. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 401

Hot, Warm, and Cold Sites . . . . . . . . . . . . . . . . . . . . . . . . . 403

Cram Quiz Answers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 406

Network Optimization Strategies. . . . . . . . . . . . . . . . . . . . . . . . . . 407

Quality of Service (QoS) . . . . . . . . . . . . . . . . . . . . . . . . . . . 407

Traffic Shaping. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 408

Caching Engines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 409

Cram Quiz Answers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 411

What Next? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 412

CHAPTER 10:

Network Security . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 413

Tunneling, Encryption, and Access Control . . . . . . . . . . . . . . . . . . . 414

Internet Security Association and Key Management Protocol

(ISAKMP). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 415

Point-to-Point Tunneling Protocol (PPTP) . . . . . . . . . . . . . . . 415

Layer 2 Tunneling Protocol (L2TP). . . . . . . . . . . . . . . . . . . . 416

IPSec . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 417

Site-to-Site and Client-to-Site. . . . . . . . . . . . . . . . . . . . . . . . 418

Overview of Access Control . . . . . . . . . . . . . . . . . . . . . . . . . 418

Remote-Access Protocols and Services . . . . . . . . . . . . . . . . . . 421

Remote-Control Protocols . . . . . . . . . . . . . . . . . . . . . . . . . . 424

MAC Filtering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 425

TCP/IP Filtering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 426

Cram Quiz Answers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 427

Authentication, Authorization, and Accounting (AAA) . . . . . . . . . . . . 429

Passwords and Password Policies . . . . . . . . . . . . . . . . . . . . . . 431

Kerberos Authentication . . . . . . . . . . . . . . . . . . . . . . . . . . . 433

Public Key Infrastructure . . . . . . . . . . . . . . . . . . . . . . . . . . . 436

RADIUS and TACACS+ . . . . . . . . . . . . . . . . . . . . . . . . . . . 439

Remote Authentication Protocols. . . . . . . . . . . . . . . . . . . . . . 440

Secured Versus Unsecured Protocols . . . . . . . . . . . . . . . . . . . 442

Adding Physical Security to the Mix . . . . . . . . . . . . . . . . . . . . 443

Two-factor and Multifactor Authentication . . . . . . . . . . . . . . . 445

Cram Quiz Answers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 448

Managing Common Security Threats . . . . . . . . . . . . . . . . . . . . . . . 449

Viruses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 450

Worms and Trojan Horses . . . . . . . . . . . . . . . . . . . . . . . . . . 451

Denial of Service and Distributed Denial of Service Attacks . . . . 452

Other Common Attacks. . . . . . . . . . . . . . . . . . . . . . . . . . . . 454

An Ounce of Prevention . . . . . . . . . . . . . . . . . . . . . . . . . . . 456

Cram Quiz Answers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 459

Firewalls and Other Appliances . . . . . . . . . . . . . . . . . . . . . . . . . . . 460

Stateful and Stateless Firewalls . . . . . . . . . . . . . . . . . . . . . . . 462

Packet-Filtering Firewalls. . . . . . . . . . . . . . . . . . . . . . . . . . . 463

Circuit-Level Firewalls . . . . . . . . . . . . . . . . . . . . . . . . . . . . 465

Application Layer Firewalls . . . . . . . . . . . . . . . . . . . . . . . . . 465

Comparing Firewall Types . . . . . . . . . . . . . . . . . . . . . . . . . . 465

Firewall Wrap-Up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 466

Demilitarized Zones (Perimeter Network) . . . . . . . . . . . . . . . . 466

Other Security Devices . . . . . . . . . . . . . . . . . . . . . . . . . . . . 467

Cram Quiz Answers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 473

What Next? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 474

CHAPTER 11:

Network Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 475

Troubleshooting Steps and Procedures . . . . . . . . . . . . . . . . . . . . . . 476

Identify the Problem . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 477

Establish a Theory of Probable Cause. . . . . . . . . . . . . . . . . . . 478

Test the Theory to Determine Cause . . . . . . . . . . . . . . . . . . . 479

Establish a Plan of Action. . . . . . . . . . . . . . . . . . . . . . . . . . . 479

Implement the Solution or Escalate . . . . . . . . . . . . . . . . . . . . 480

Verify Full System Functionality . . . . . . . . . . . . . . . . . . . . . . 481

Document the Findings, Actions, and Outcomes. . . . . . . . . . . . 482

Cram Quiz Answers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 484

Troubleshooting the Network . . . . . . . . . . . . . . . . . . . . . . . . . . . . 485

Common Problems to Be Aware Of . . . . . . . . . . . . . . . . . . . . 485

Troubleshooting Wiring . . . . . . . . . . . . . . . . . . . . . . . . . . . 490

Wiring Issues. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 492

Troubleshooting Infrastructure Hardware . . . . . . . . . . . . . . . . 496

Configuring and Troubleshooting Client Connectivity . . . . . . . . 498

Troubleshooting an Incorrect VLAN . . . . . . . . . . . . . . . . . . . 503

Topology Errors. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 504

Cram Quiz Answers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 510

What Next? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 511

Practice Exam 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 513

Exam Questions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 513

Answers to Practice Exam 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 537

Answers at a Glance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 537

Answers and Explanations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 538

Practice Exam 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 561

Exam Questions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 561

Answers to Practice Exam 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 585

Answers at a Glance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 585

Answers and Explanations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 586

Glossary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 607

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Overview


Pearson Education, Inc., 221 River Street, Hoboken, New Jersey 07030, (Pearson) presents this site to provide information about products and services that can be purchased through this site.

This privacy notice provides an overview of our commitment to privacy and describes how we collect, protect, use and share personal information collected through this site. Please note that other Pearson websites and online products and services have their own separate privacy policies.

Collection and Use of Information


To conduct business and deliver products and services, Pearson collects and uses personal information in several ways in connection with this site, including:

Questions and Inquiries

For inquiries and questions, we collect the inquiry or question, together with name, contact details (email address, phone number and mailing address) and any other additional information voluntarily submitted to us through a Contact Us form or an email. We use this information to address the inquiry and respond to the question.

Online Store

For orders and purchases placed through our online store on this site, we collect order details, name, institution name and address (if applicable), email address, phone number, shipping and billing addresses, credit/debit card information, shipping options and any instructions. We use this information to complete transactions, fulfill orders, communicate with individuals placing orders or visiting the online store, and for related purposes.

Surveys

Pearson may offer opportunities to provide feedback or participate in surveys, including surveys evaluating Pearson products, services or sites. Participation is voluntary. Pearson collects information requested in the survey questions and uses the information to evaluate, support, maintain and improve products, services or sites, develop new products and services, conduct educational research and for other purposes specified in the survey.

Contests and Drawings

Occasionally, we may sponsor a contest or drawing. Participation is optional. Pearson collects name, contact information and other information specified on the entry form for the contest or drawing to conduct the contest or drawing. Pearson may collect additional personal information from the winners of a contest or drawing in order to award the prize and for tax reporting purposes, as required by law.

Newsletters

If you have elected to receive email newsletters or promotional mailings and special offers but want to unsubscribe, simply email information@informit.com.

Service Announcements

On rare occasions it is necessary to send out a strictly service related announcement. For instance, if our service is temporarily suspended for maintenance we might send users an email. Generally, users may not opt-out of these communications, though they can deactivate their account information. However, these communications are not promotional in nature.

Customer Service

We communicate with users on a regular basis to provide requested services and in regard to issues relating to their account we reply via email or phone in accordance with the users' wishes when a user submits their information through our Contact Us form.

Other Collection and Use of Information


Application and System Logs

Pearson automatically collects log data to help ensure the delivery, availability and security of this site. Log data may include technical information about how a user or visitor connected to this site, such as browser type, type of computer/device, operating system, internet service provider and IP address. We use this information for support purposes and to monitor the health of the site, identify problems, improve service, detect unauthorized access and fraudulent activity, prevent and respond to security incidents and appropriately scale computing resources.

Web Analytics

Pearson may use third party web trend analytical services, including Google Analytics, to collect visitor information, such as IP addresses, browser types, referring pages, pages visited and time spent on a particular site. While these analytical services collect and report information on an anonymous basis, they may use cookies to gather web trend information. The information gathered may enable Pearson (but not the third party web trend services) to link information with application and system log data. Pearson uses this information for system administration and to identify problems, improve service, detect unauthorized access and fraudulent activity, prevent and respond to security incidents, appropriately scale computing resources and otherwise support and deliver this site and its services.

Cookies and Related Technologies

This site uses cookies and similar technologies to personalize content, measure traffic patterns, control security, track use and access of information on this site, and provide interest-based messages and advertising. Users can manage and block the use of cookies through their browser. Disabling or blocking certain cookies may limit the functionality of this site.

Do Not Track

This site currently does not respond to Do Not Track signals.

Security


Pearson uses appropriate physical, administrative and technical security measures to protect personal information from unauthorized access, use and disclosure.

Children


This site is not directed to children under the age of 13.

Marketing


Pearson may send or direct marketing communications to users, provided that

  • Pearson will not use personal information collected or processed as a K-12 school service provider for the purpose of directed or targeted advertising.
  • Such marketing is consistent with applicable law and Pearson's legal obligations.
  • Pearson will not knowingly direct or send marketing communications to an individual who has expressed a preference not to receive marketing.
  • Where required by applicable law, express or implied consent to marketing exists and has not been withdrawn.

Pearson may provide personal information to a third party service provider on a restricted basis to provide marketing solely on behalf of Pearson or an affiliate or customer for whom Pearson is a service provider. Marketing preferences may be changed at any time.

Correcting/Updating Personal Information


If a user's personally identifiable information changes (such as your postal address or email address), we provide a way to correct or update that user's personal data provided to us. This can be done on the Account page. If a user no longer desires our service and desires to delete his or her account, please contact us at customer-service@informit.com and we will process the deletion of a user's account.

Choice/Opt-out


Users can always make an informed choice as to whether they should proceed with certain services offered by InformIT. If you choose to remove yourself from our mailing list(s) simply visit the following page and uncheck any communication you no longer want to receive: www.informit.com/u.aspx.

Sale of Personal Information


Pearson does not rent or sell personal information in exchange for any payment of money.

While Pearson does not sell personal information, as defined in Nevada law, Nevada residents may email a request for no sale of their personal information to NevadaDesignatedRequest@pearson.com.

Supplemental Privacy Statement for California Residents


California residents should read our Supplemental privacy statement for California residents in conjunction with this Privacy Notice. The Supplemental privacy statement for California residents explains Pearson's commitment to comply with California law and applies to personal information of California residents collected in connection with this site and the Services.

Sharing and Disclosure


Pearson may disclose personal information, as follows:

  • As required by law.
  • With the consent of the individual (or their parent, if the individual is a minor)
  • In response to a subpoena, court order or legal process, to the extent permitted or required by law
  • To protect the security and safety of individuals, data, assets and systems, consistent with applicable law
  • In connection the sale, joint venture or other transfer of some or all of its company or assets, subject to the provisions of this Privacy Notice
  • To investigate or address actual or suspected fraud or other illegal activities
  • To exercise its legal rights, including enforcement of the Terms of Use for this site or another contract
  • To affiliated Pearson companies and other companies and organizations who perform work for Pearson and are obligated to protect the privacy of personal information consistent with this Privacy Notice
  • To a school, organization, company or government agency, where Pearson collects or processes the personal information in a school setting or on behalf of such organization, company or government agency.

Links


This web site contains links to other sites. Please be aware that we are not responsible for the privacy practices of such other sites. We encourage our users to be aware when they leave our site and to read the privacy statements of each and every web site that collects Personal Information. This privacy statement applies solely to information collected by this web site.

Requests and Contact


Please contact us about this Privacy Notice or if you have any requests or questions relating to the privacy of your personal information.

Changes to this Privacy Notice


We may revise this Privacy Notice through an updated posting. We will identify the effective date of the revision in the posting. Often, updates are made to provide greater clarity or to comply with changes in regulatory requirements. If the updates involve material changes to the collection, protection, use or disclosure of Personal Information, Pearson will provide notice of the change through a conspicuous notice on this site or other appropriate way. Continued use of the site after the effective date of a posted revision evidences acceptance. Please contact us if you have questions or concerns about the Privacy Notice or any objection to any revisions.

Last Update: November 17, 2020