NETWORKING QUIZ

Mike Meyers’

CompTIA Network+® Guide to Managing and

Troubleshooting Networks

Third Edition

(Exam N10-005)

 

 

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Mike Meyers’

CompTIA Network+® Guide to Managing and

Troubleshooting Networks

Third Edition

(Exam N10-005)

Mike Meyers

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About the Author■■ Michael Meyers is the industry’s leading authority on CompTIA Network+ certifica- tion. He is the president and founder of Total Seminars, LLC, a major provider of PC and network repair seminars for thousands of organizations throughout the world, and a member of CompTIA.

Mike has written numerous popular textbooks, including the best-selling Mike Meyers’ CompTIA A+® Guide to Managing & Troubleshooting PCs, Mike Meyers’ CompTIA A+® Guide to Essentials, and Mike Meyers’ CompTIA A+® Guide to Operating Systems.

About the Contributor Scott Jernigan wields a mighty red pen as Editor in Chief for Total Seminars. With a Master of Arts degree in Medieval History, Scott feels as much at home in the musty archives of London as he does in the warm CRT glow of Total Seminars’ Houston head- quarters. After fleeing a purely academic life, he dove headfirst into IT, working as an instructor, editor, and writer.

Scott has written, edited, and contributed to dozens of books on computer liter- acy, hardware, operating systems, networking, and certification, including Computer Literacy—Your Ticket to IC3 Certification, and co-authoring with Mike Meyers the All-in- One CompTIA Strata® IT Fundamentals Exam Guide.

Scott has taught computer classes all over the United States, including stints at the United Nations in New York and the FBI Academy in Quantico. Practicing what he preaches, Scott is a CompTIA A+ and CompTIA Network+ certified technician, a Microsoft Certified Professional, a Microsoft Office User Specialist, and Certiport Inter- net and Computing Core Certified.

About the Technical Editor Jonathan S. Weissman earned his master’s degree in Computer and Information Science from Brooklyn College (CUNY), and holds nineteen industry certifications, including Cisco CCNA, CompTIA Security+, CompTIA i-Net+, CompTIA Network+, CompTIA A+, CompTIA Linux+, Novell CNE, Novell CNA, Microsoft Office Master, Microsoft MCAS Word, Microsoft MCAS PowerPoint, Microsoft MCAS Excel, Microsoft MCAS Access, Microsoft MCAS Outlook, and Microsoft MCAS Vista.

Jonathan is a tenured Assistant Professor of Computing Sciences at Finger Lakes Community College, in Canandaigua, NY, and also teaches graduate and under- graduate computer science courses at nearby Rochester Institute of Technology. In addi- tion, Jonathan does computer, network, and security consulting for area businesses and individuals.

Between FLCC and RIT, Jonathan has taught nearly two dozen different computer science courses, including networking, security, administration, forensics, program- ming, operating systems, hardware, and software.

Students evaluating his teaching emphasize that he simplifies their understanding of difficult topics, while at the same time makes the class interesting and entertaining.

Jonathan completely designed and configured FLCC’s newest Networking & Secu- rity Lab. Serving as IT Program Coordinator, he rewrote FLCC’s Information Technol- ogy course requirements for the degree, keeping it current with the changes in industry over the years.

This textbook is just one of the many that Jonathan has edited for thoroughness and accuracy.

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vii

Acknowledgments■■ I’d like to acknowledge the many people who contributed their talents to make this book possible:

To Tim Green, my acquisitions editor at McGraw-Hill: Didn’t think I’d get the book out this quickly, did you? Thanks for your superb support and encouragement, as always.

To my in-house Editor-in-Chief, Scott Jernigan: Didn’t think we’d get the book out that fast, did you? How many 85s do you have now? Pelape still smokes them all in DPS.

To Jonathan Weissman, technical editor: Holy crap, you kicked my butt. Thanks for making my book dramatically better than it has ever been.

To LeeAnn Pickrell, copy editor: u made me write good, thx. To Michael Smyer, Total Seminars’ resident tech guru and photogra-

pher: Glad to see you staying focused. And your photos rocked as always! To Ford Pierson, graphics maven and editor: Superb conceptual art?

Check! Great editing? Check! Beating the boss in Unreal Tournament over and over again? Check, unfortunately.

To Aaron Verber, editor extraordinaire: Your quiet toils in the dark cor- ner of the office have once again paid outstanding dividends!

To Dudley Lehmer, my partner at Total Seminars: As always, thanks for keeping the ship afloat while I got to play on this book!

To Stephanie Evans, acquisitions coordinator at McGraw-Hill: You are my favorite South African ambassador since the Springboks. Thanks for keeping track of everything and (gently) smacking Scott when he forgot things.

To Molly Sharp and Jody McKenzie, project editors: It was a joy to work with you, Molly, and again with you, Jody. I couldn’t have asked for a better team! (Didn’t think I could resist making the pun, did you?)

To Andrea Fox, proofreader: You did a super job, thank you To Tom and Molly Sharp, compositors: The layout was excellent,

thanks!

To Staci Lynne ■■ Davis, vegan chef and

punk rocker: Thanks for showing me your world

and, in the process, expanding mine.

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Key Terms, identified in red, point out important vocabulary and definitions that you need to know.

Tech Tip sidebars provide inside information from experienced IT professionals.

Cross Check questions develop reasoning skills: ask, compare, contrast, and explain.

Engaging and Motivational— Using a conversational style and proven instructional approach, the author explains technical concepts in a clear, interesting way using real-world examples.

Makes Learning Fun!— Rich, colorful text and enhanced illustrations bring technical subjects to life.

10BaseT also introduced the networking world to the RJ-45 connector (Figure 4.9). Each pin on the RJ-45 connects to a single wire inside the cable; this enables de- vices to put voltage on the indi- vidual wires within the cable. The pins on the RJ-45 are numbered from 1 to 8, as shown in Figure 4.10.

The 10BaseT standard designates some of these numbered wires for specific purposes. As mentioned earlier, although the cable has four pairs, 10BaseT uses only two of the pairs. 10BaseT devices use pins 1 and 2 to send data, and pins 3 and 6 to receive data. Even though one pair of wires sends data and another receives data, a 10BaseT device cannot send and receive simul- taneously. The rules of CSMA/CD still apply: only one device can use the segment contained in the hub without causing a collision. Later versions of Ethernet will change this rule.

An RJ-45 connector is usually called a crimp, and the act (some folks call it an art) of installing a crimp onto the end of a piece of UTP cable is called crimping. The tool used to secure a crimp onto the end of a cable is a crimper. Each wire inside a UTP cable must connect to the proper pin inside the crimp. Manufacturers color-code each wire within a piece of four-pair UTP to assist in properly matching the ends. Each pair of wires consists of a solid- colored wire and a striped wire: blue/blue-white, orange/orange-white, brown/brown-white, and green/green-white (Figure 4.11).

The Telecommunications Industry Association/Electronics Industries Alliance (TIA/EIA) defines the industry standard for correct crimping of four-pair UTP for 10BaseT networks. Two standards currently exist: TIA/ EIA 568A and TIA/EIA 568B. Figure 4.12 shows the TIA/EIA 568A and TIA/ EIA 568B color-code standards. Note that the wire pairs used by 10BaseT (1 and 2; 3 and 6) come from the same color pairs (green/green-white and orange/orange-white). Following an established color-code scheme, such as TIA/EIA 568A, ensures that the wires match up correctly at each end of the cable.

66 Mike Meyers’ CompTIA Network+ Guide to Managing and Troubleshooting Networks

Cross Check Check Your CATs!

You’ve already seen CAT levels in Chapter 3, “Cabling and Topology,” so check your memory and review the different speeds of the various CAT levels. Could 10BaseT use CAT 2? Could it use CAT 6? What types of devices can use CAT 1?

• Figure 4.9 Two views of an RJ-45 connector

• Figure 4.10 The pins on an RJ-45 connector are numbered 1 through 8.

• Figure 4.11 Color-coded pairs

The real name for RJ-45 is “8 Position 8 Contact (8P8C) modular plug.” The name RJ-45 is so dominant, however, that nobody but the nerdiest of nerds calls it by its real name. Stick to RJ-45.

AbouT ThIs book

Proven Learning Method Keeps You on Track Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks is structured to give you comprehensive knowledge of computer skills and technologies. The textbook’s active learning methodology guides you beyond mere recall and—through thought-provoking activities, labs, and sidebars—helps you develop critical-thinking, diagnostic, and communication skills.

Information technology (IT) offers many career paths, leading to occupations in such fields as PC repair, network administration, telecommunications, Web development, graphic design, and desktop support. To become competent in any IT field, however, you need

certain basic computer skills. Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks builds a foundation for success in the IT field by introducing you to fundamental technology concepts and giving you essential computer skills.

Important Technology skills ■

10BaseT also introduced the networking world to the RJ-45 connector (Figure 4.9). Each pin on the RJ-45 connects to a single wire inside the cable; this enables de- vices to put voltage on the indi- vidual wires within the cable. The pins on the RJ-45 are numbered from 1 to 8, as shown in Figure 4.10.

The 10BaseT standard designates some of these numbered wires for specific purposes. As mentioned earlier, although the cable has four pairs, 10BaseT uses only two of the pairs. 10BaseT devices use pins 1 and 2 to send data, and pins 3 and 6 to receive data. Even though one pair of wires sends data and another receives data, a 10BaseT device cannot send and receive simul- taneously. The rules of CSMA/CD still apply: only one device can use the segment contained in the hub without causing a collision. Later versions of Ethernet will change this rule.

An RJ-45 connector is usually called a crimp, and the act (some folks call it an art) of installing a crimp onto the end of a piece of UTP cable is called crimping. The tool used to secure a crimp onto the end of a cable is a crimper. Each wire inside a UTP cable must connect to the proper pin inside the crimp. Manufacturers color-code each wire within a piece of four-pair UTP to assist in properly matching the ends. Each pair of wires consists of a solid- colored wire and a striped wire: blue/blue-white, orange/orange-white, brown/brown-white, and green/green-white (Figure 4.11).

The Telecommunications Industry Association/Electronics Industries Alliance (TIA/EIA) defines the industry standard for correct crimping of four-pair UTP for 10BaseT networks. Two standards currently exist: TIA/ EIA 568A and TIA/EIA 568B. Figure 4.12 shows the TIA/EIA 568A and TIA/ EIA 568B color-code standards. Note that the wire pairs used by 10BaseT (1 and 2; 3 and 6) come from the same color pairs (green/green-white and orange/orange-white). Following an established color-code scheme, such as TIA/EIA 568A, ensures that the wires match up correctly at each end of the cable.

66 Mike Meyers’ CompTIA Network+ Guide to Managing and Troubleshooting Networks

Cross Check Check Your CATs!

You’ve already seen CAT levels in Chapter 3, “Cabling and Topology,” so check your memory and review the different speeds of the various CAT levels. Could 10BaseT use CAT 2? Could it use CAT 6? What types of devices can use CAT 1?

• Figure 4.9 Two views of an RJ-45 connector

• Figure 4.10 The pins on an RJ-45 connector are numbered 1 through 8.

• Figure 4.11 Color-coded pairs

The real name for RJ-45 is “8 Position 8 Contact (8P8C) modular plug.” The name RJ-45 is so dominant, however, that nobody but the nerdiest of nerds calls it by its real name. Stick to RJ-45.

10BaseT also introduced the networking world to the RJ-45 connector (Figure 4.9). Each pin on the RJ-45 connects to a single wire inside the cable; this enables de- vices to put voltage on the indi- vidual wires within the cable. The pins on the RJ-45 are numbered from 1 to 8, as shown in Figure 4.10.

The 10BaseT standard designates some of these numbered wires for specific purposes. As mentioned earlier, although the cable has four pairs, 10BaseT uses only two of the pairs. 10BaseT devices use pins 1 and 2 to send data, and pins 3 and 6 to receive data. Even though one pair of wires sends data and another receives data, a 10BaseT device cannot send and receive simul- taneously. The rules of CSMA/CD still apply: only one device can use the segment contained in the hub without causing a collision. Later versions of Ethernet will change this rule.

An RJ-45 connector is usually called a crimp, and the act (some folks call it an art) of installing a crimp onto the end of a piece of UTP cable is called crimping. The tool used to secure a crimp onto the end of a cable is a crimper. Each wire inside a UTP cable must connect to the proper pin inside the crimp. Manufacturers color-code each wire within a piece of four-pair UTP to assist in properly matching the ends. Each pair of wires consists of a solid- colored wire and a striped wire: blue/blue-white, orange/orange-white, brown/brown-white, and green/green-white (Figure 4.11).

The Telecommunications Industry Association/Electronics Industries Alliance (TIA/EIA) defines the industry standard for correct crimping of four-pair UTP for 10BaseT networks. Two standards currently exist: TIA/ EIA 568A and TIA/EIA 568B. Figure 4.12 shows the TIA/EIA 568A and TIA/ EIA 568B color-code standards. Note that the wire pairs used by 10BaseT (1 and 2; 3 and 6) come from the same color pairs (green/green-white and orange/orange-white). Following an established color-code scheme, such as TIA/EIA 568A, ensures that the wires match up correctly at each end of the cable.

66 Mike Meyers’ CompTIA Network+ Guide to Managing and Troubleshooting Networks

Cross Check Check Your CATs!

You’ve already seen CAT levels in Chapter 3, “Cabling and Topology,” so check your memory and review the different speeds of the various CAT levels. Could 10BaseT use CAT 2? Could it use CAT 6? What types of devices can use CAT 1?

• Figure 4.9 Two views of an RJ-45 connector

• Figure 4.10 The pins on an RJ-45 connector are numbered 1 through 8.

• Figure 4.11 Color-coded pairs

The real name for RJ-45 is “8 Position 8 Contact (8P8C) modular plug.” The name RJ-45 is so dominant, however, that nobody but the nerdiest of nerds calls it by its real name. Stick to RJ-45.

/ Mike Meyers’ CompTIA Network+ Guide to Managing and Troubleshooting Networks, Third Edition / Meyers / 911-1 / fm blind folio ix

 

 

consider that type of NIC. The spe- cific process by which a NIC uses electricity to send and receive data is exceedingly complicated, but luck- ily for you, not necessary to under- stand. Instead, just think of a charge on the wire as a one, and no charge as a zero. A chunk of data moving in pulses across a wire might look something like Figure 2.13.

If you put an oscilloscope on the wire to measure voltage, you’d see something like Figure 2.14. An oscilloscope is a powerful micro- scope that enables you to see elec- trical pulses.

Now, remembering that the pulses represent bi- nary data, visualize instead a string of ones and zeroes moving across the wire (Figure 2.15).

Once you understand how data moves along the wire, the next question becomes this: how does the net- work get the right data to the right system? All networks transmit data by breaking whatever is moving across the physical layer (files, print jobs, Web pages, and so forth) into discrete chunks called frames. A frame is basically a container for a chunk of data moving across a network. The NIC creates and sends, as well as receives and reads, these frames.

I like to visualize an imaginary table inside every NIC that acts as a frame creation and reading station. I see frames as those pneumatic canis- ters you see when you go to a drive-in teller at a bank. A little guy inside the network card—named Nick, naturally!—builds these pneumatic canisters (the frames) on the table, and then shoots them out on the wire to the hub (Figure 2.16).

Chapter 2: Building a Network with the OSI Model 15

Try This! What’s Your MAC Address?

You can readily determine your MAC address on a Windows computer from the command line. This works in all modern versions of Windows.

1. In Windows 2000/XP, click Start | Run. Enter the command CMD and press the ENTER key to get to a command prompt.

2. In Windows Vista, click Start, enter CMD in the Start Search text box, and press the ENTER key to get to a command prompt.

3. At the command prompt, type the command IPCONFIG /ALL and press the ENTER key.

• Figure 2.13 Data moving along a wire

• Figure 2.14 Oscilloscope of data

• Figure 2.15 Data as ones and zeroes

• Figure 2.16 Inside the NIC

A number of different frame types are used in different net- works. All NICs on the same net- work must use the same frame type or they will not be able to communicate with other NICs.

Each chapter includes Learning Objectives ■ that set measurable goals for chapter-by-chapter progress

Illustrations ■ that give you a clear picture of the technologies

Tutorials ■ that teach you to perform essential tasks and procedures hands-on

Try This!, Cross Check ■ , and Tech Tip sidebars that encourage you to practice and apply concepts in real-world settings

Notes, Tips ■ , and Warnings that guide you through difficult areas

Chapter Summaries ■ and Key Terms Lists that provide you with an easy way to review important concepts and vocabulary

Challenging End-of-Chapter Tests ■ that include vocabulary-building exercises, multiple-choice questions, essay questions, and on-the-job lab projects

This pedagogically rich book is designed to make learning easy and enjoyable and to help you develop the skills and critical-thinking abilities that will enable you to adapt to different job situations and troubleshoot problems.

Mike Meyers’ proven ability to explain concepts in a clear, direct, even humorous way makes this book interesting, motivational, and fun.

Effective Learning Tools ■

Proven Learning Method Keeps You on Track Mike Meyers’ CompTIA Network+® Guide to Managing and Troubleshooting Networks is structured to give you comprehensive knowledge of computer skills and technologies. The textbook’s active learning methodology guides you beyond mere recall and—through thought-provoking activities, labs, and sidebars—helps you develop critical-thinking, diagnostic, and communication skills.

Try This! exercises apply core skills in a new setting.

Chapter Review sections provide concept summaries, key terms lists, and lots of questions and projects.

Key Terms Lists presents the important terms identified in the chapter.

Offers Practical Experience— Tutorials and lab assignments develop essential hands-on skills and put concepts in real-world contexts.

Robust Learning Tools— Summaries, key terms lists, quizzes, essay questions, and lab projects help you practice skills and measure progress.

Notes,Tips, and Warnings create a road map for success.

consider that type of NIC. The spe- cific process by which a NIC uses electricity to send and receive data is exceedingly complicated, but luck- ily for you, not necessary to under- stand. Instead, just think of a charge on the wire as a one, and no charge as a zero. A chunk of data moving in pulses across a wire might look something like Figure 2.13.

If you put an oscilloscope on the wire to measure voltage, you’d see something like Figure 2.14. An oscilloscope is a powerful micro- scope that enables you to see elec- trical pulses.

Now, remembering that the pulses represent bi- nary data, visualize instead a string of ones and zeroes moving across the wire (Figure 2.15).

Once you understand how data moves along the wire, the next question becomes this: how does the net- work get the right data to the right system? All networks transmit data by breaking whatever is moving across the physical layer (files, print jobs, Web pages, and so forth) into discrete chunks called frames. A frame is basically a container for a chunk of data moving across a network. The NIC creates and sends, as well as receives and reads, these frames.

I like to visualize an imaginary table inside every NIC that acts as a frame creation and reading station. I see frames as those pneumatic canis- ters you see when you go to a drive-in teller at a bank. A little guy inside the network card—named Nick, naturally!—builds these pneumatic canisters (the frames) on the table, and then shoots them out on the wire to the hub (Figure 2.16).

Chapter 2: Building a Network with the OSI Model 15

Try This! What’s Your MAC Address?

You can readily determine your MAC address on a Windows computer from the command line. This works in all modern versions of Windows.

1. In Windows 2000/XP, click Start | Run. Enter the command CMD and press the ENTER key to get to a command prompt.

2. In Windows Vista, click Start, enter CMD in the Start Search text box, and press the ENTER key to get to a command prompt.

3. At the command prompt, type the command IPCONFIG /ALL and press the ENTER key.

• Figure 2.13 Data moving along a wire

• Figure 2.14 Oscilloscope of data

• Figure 2.15 Data as ones and zeroes

• Figure 2.16 Inside the NIC

A number of different frame types are used in different net- works. All NICs on the same net- work must use the same frame type or they will not be able to communicate with other NICs.

consider that type of NIC. The spe- cific process by which a NIC uses electricity to send and receive data is exceedingly complicated, but luck- ily for you, not necessary to under- stand. Instead, just think of a charge on the wire as a one, and no charge as a zero. A chunk of data moving in pulses across a wire might look something like Figure 2.13.

If you put an oscilloscope on the wire to measure voltage, you’d see something like Figure 2.14. An oscilloscope is a powerful micro- scope that enables you to see elec- trical pulses.

Now, remembering that the pulses represent bi- nary data, visualize instead a string of ones and zeroes moving across the wire (Figure 2.15).

Once you understand how data moves along the wire, the next question becomes this: how does the net- work get the right data to the right system? All networks transmit data by breaking whatever is moving across the physical layer (files, print jobs, Web pages, and so forth) into discrete chunks called frames. A frame is basically a container for a chunk of data moving across a network. The NIC creates and sends, as well as receives and reads, these frames.

I like to visualize an imaginary table inside every NIC that acts as a frame creation and reading station. I see frames as those pneumatic canis- ters you see when you go to a drive-in teller at a bank. A little guy inside the network card—named Nick, naturally!—builds these pneumatic canisters (the frames) on the table, and then shoots them out on the wire to the hub (Figure 2.16).

Chapter 2: Building a Network with the OSI Model 15

Try This! What’s Your MAC Address?

You can readily determine your MAC address on a Windows computer from the command line. This works in all modern versions of Windows.

1. In Windows 2000/XP, click Start | Run. Enter the command CMD and press the ENTER key to get to a command prompt.

2. In Windows Vista, click Start, enter CMD in the Start Search text box, and press the ENTER key to get to a command prompt.

3. At the command prompt, type the command IPCONFIG /ALL and press the ENTER key.

• Figure 2.13 Data moving along a wire

• Figure 2.14 Oscilloscope of data

• Figure 2.15 Data as ones and zeroes

• Figure 2.16 Inside the NIC

A number of different frame types are used in different net- works. All NICs on the same net- work must use the same frame type or they will not be able to communicate with other NICs.

BaseTech