comptia network+ (n10-002)

Lesson Plans

CompTIA’s Network+

(Exam N10-002)

Table of ContentsTable of Contents...............................................................................................................1Course Overview................................................................................................................2Course Preparation...........................................................................................................4Section 1-1: Networking Theory.......................................................................................5Section 1-2: Standards Organizations.............................................................................8Section 1-3: A Typical Computer Network...................................................................10Section 1-4: Varieties of Computer Networks...............................................................13Section 2-1: The OSI Application Layer.......................................................................16Section 2-2: The OSI Presentation Layer......................................................................18Section 2-3: The OSI Session Layer...............................................................................21Section 2-4: The OSI Transport Layer..........................................................................23Section 2-5: The OSI Network Layer.............................................................................25Section 2-6: The OSI Data Link Layer..........................................................................28Section 2-7: The OSI Physical Layer.............................................................................31Section 2-8: Multi-Layer Concepts................................................................................34Section 3-1: Cables and Connectors...............................................................................36Section 3-2: Ethernet (IEEE 802.3)................................................................................39Section 3-3: Other LAN Standards................................................................................43Section 3-4: WAN Links..................................................................................................46Section 4-1: Common Protocol Suites............................................................................50Section 4-2: TCP/IP.........................................................................................................56Section 5-1: Security........................................................................................................64Section 5-2: Fault Tolerance...........................................................................................69Section 5-3: Performance................................................................................................72Section 6-1: Installation...................................................................................................74Section 6-2: Maintenance................................................................................................77Section 6-3: Troubleshooting..........................................................................................79Appendix A: Network+ Exam Objectives.....................................................................83

©2002 TestOut Corporation (Rev 11/02)CompTIA Network+ (N10-002)

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Course OverviewThis course prepares students for the Microsoft certification Exam N10-002, CompTIA's Network+ Certification.

Before beginning the Network+ course, students should have a basic knowledge of computer hardware and software. CompTIA's A+ certification is excellent preparation. Recommend that students consider completing the following courses:

o TestOut for CompTIA's A+ Core Hardwareo TestOut for CompTIA's A+ Operating System Technologies

Module 1Module 1 introduces the concept of a network.

Module 2Module 2 explains details of the OSI model.

Module 3Module 3 introduces Physical and Data Link standards used to build a network's foundation.

Module 4Module 4 introduces common protocols that correspond to the upper layers of the OSI model. The focus is the TCP/IP protocol suite.

Module 5Module 5 explains principles for managing access to the network and its resources.

Module 6Module 6 explains and summarizes several network administration tips.

Module 7Module 7 reviews details for the Network+ exam. It is meant to be used as a final review and study guide.

Network+ Exam FocusThis section of each lesson plan summarizes the most important topics for the Network+ exam. If your course focuses on exam preparation, be sure to emphasize these topics.

Lab/ActivitiesThis section of each lesson plan contains two different types of activities that can be adapted to your classroom environment. Lecture activities can be presented on the board or with handouts. They do not require student computers, so they work well in a


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traditional classroom. Computer lab activities require a lab where students are able to configure their own computers. If you don’t teach in a computer lab, the computer lab activities can be used as homework.

Homework SuggestionsRequire each student to maintain a lab notebook. This could be a simple spiral notebook or a three-ring binder. As part of their homework and during lab activities, have students record/document the steps required to complete certain procedures. Recording procedures reinforces steps and concepts, and gives the student a place to look for directions when they want to repeat a task, but don’t remember the exact procedure. It also provides an assessment tool for the instructor.

The Homework Suggestions section also lists the focus question for the next section. Present this question at the end of class. Start each class with the focus question presented in the previous class. Encourage students to be prepared to answer the question, but make sure they understand that you don’t need a complete answer. You want them to preview the next section for a basic answer. This can help stimulate a better quality discussion and questions during the lecture. It will also help you assess student understanding of the topic.

Consider the focus question for Section 1-3. What are the major components of a computer network? Students should be able to provide simple responses such as:

Resources, servers, and clients. Connectivity devices like routers and hubs.


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Course Preparation

In AdvanceSetup TestOut courseware and create student accounts. You may want to arrange a tour of your building’s infrastructure. It’s a great way to enforce networking concepts.

Instructor computer setupInstall Windows 2000 Server on the instructor computer. You may want to set up the computer to dual boot between Windows 2000 server and Professional. Most of the concepts can be adequately demonstrated on Windows 2000 Professional computer. However, there are a few places where a server is helpful. For example, in Section 2-5, if you are running Windows 2000 Server you can use your computer to demonstrate routing concepts. This material assumes you are running Windows 2000, but you could also use Windows NT 4.0.

Ideally, your classroom hub or switch will be accessible so you can unplug the classroom network from the rest of the network. This allows you to practice items that are potentially disruptive. When running something that is potentially disruptive, simply unplug the classroom until the practice is over. For example, when students practice assigning IP addresses, unplug the classroom so you don’t have to worry about duplicate IP addresses.

Student computer setup Computers need to be able to run the TestOut material. Because the TestOut material contains audio, computer should have sound cards. You may want to require students to bring their own headphones or provide them. The suggested computer labs were written for Windows 2000 Professional computers, but most labs can be adapted to other Windows operating systems.

One way to create this a practice lab is to use removable hard drives in the student computers. Students check out the drives for their classes. This allows you to teach multiple classes in a single lab, while preventing one class from damaging or destroying the installations used by another class. To facilitate the frequent computer operating system rebuilds required by this type of lab, consider investing in disk duplication software. You could also create unattended installation files to automate the baseline Windows 2000 installations needed for the lab computers.


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Section 1-1: Networking Theory

PreparationThis section introduces basic networking concepts. Before class, make sure the courseware is installed and student accounts have been created.

Exam Objectives 2.2 Identify the seven layers of the OSI model and their functions.3.5 Identify the purpose and characteristics of fault tolerance.3.6 Identify the purpose and characteristics of disaster recovery.

Vocabulary: network, resource, service, client, OSI model, application layer, presentation layer, session layer, transport layer, network layer, data link layer, physical layer

Focus Question: What is a computer network?

TimeAbout 2 hours

Network+ Exam FocusNetwork Components

Router - A device that connects two or more segments of a network with different IDs, and routes data between each segment.

Hub - A device that connects multiple computers together in a local area network. When a packet arrives at one port, it is copied to the other ports so that all segments of the LAN can see all packets.

Switch - A hub that directs a network packet only to the destination host's port instead of all ports, as a normal hub does. Doing so increases network performance.

Repeater - A device that baseband networking systems use to regenerate digital signals when they attenuate.

Gateway - Any device that translates between protocols. A gateway can be hardware or software based.

OSI Model Be able to recite the OSI layers in order, identify the main purpose of each layer,

and associate devices with the correct layer.

Lecture Tips Introduce Instructor. Have each student introduce themselves, explain why they are taking the course,

and what they hope to get out of it. Hand out and explain syllabus, lab policies, and any other required introductory

material.


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Explain the lab notebook to students and make sure they understand that they must have a notebook for the next class session.

Demonstrate login to network. Demonstrate how to access the courseware. Counsel students who don’t meet the prerequisite requirements. Before beginning

the Network+ course, students should have a basic knowledge of computer hardware and software. CompTIA's A+ certification is excellent preparation.

Introduce the concept of a computer network.o Computers connected to exchange information.

Define network resources, services, and clients. Briefly introduce the OSI model. Explain the function of each OSI layer.

o Application layer.o Presentation layer.o Session layer.o Transport layer.o Network layer.o Data link layer.o Physical layer.

Introduce OSI mnemonics.o All People Should Transport Network Data Physically.o Please Do Not Throw Sausage Pizza Away.

Introduce managing network access.o Define network security.o Define network fault tolerance.o Define network performance.

Introduce common network administration tasks.o Installation.o Maintenance.o Troubleshooting.

Lab/ActivityLecture Activity

Have the class recite the OSI mnemonics aloud a few times. Try activities to help students put the OSI layers in the correct order, and identify

function of each layer. o Label cards with OSI layers and hand them out to the class. Have students

line up in the correct order. o Have students write the OSI layers in order three times. o Bring labeled blocks and ask students to stack them. o Give a student a function and ask him or her to identify the layer.o Give a student a layer and ask him or her to identify the function.

The following idea would make a nice pop quiz for the next class period. o Write the OSI layers in order and define the main purpose of each layer.

Computer Lab Activity Log on to the network and start the courseware.


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AssessmentUse the introduction to basic networking terms to check prerequisite background. As students log on and start the courseware, check for basic interface skills. Students who have trouble finding the Start Menu or using the mouse probably belong in a basic skills course.

Homework Suggestions Read Section 1-1 and take the section test. Research the focus question for the next section.

o How are networking standards set?


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Section 1-2: Standards Organizations

PreparationThis section introduces several organizations that are involved in setting networking standards.

Vocabulary: ISO, IEEE, ISOC, InterNIC, ICANN, IEC, ANSI, ITU, EIA/TIA, RFC

Focus Question: How are networking standards set?

TimeAbout 30 minutes

Network+ Exam FocusThis section does not directly address any exam objectives. However, some of these organizations are mentioned later in the course when students are introduced to standards. For example, exam requirements include knowledge of the IEEE 802.2 standard.

. Tips Start with the focus question. Do students have any questions about the material

they have studied? Briefly discuss the role of each of the standards organizations.

o ISOo IEEEo ISOC

Discuss RFCs.o InterNICo ICANN o IECo ANSIo ITUo EIA/TIA

Lab/ActivityComputer Lab Activity

Go to http://www.icann.org/ and find out how to register for an Internet domain name.

AssessmentCheck lab notebooks.

Homework Suggestions Read Section 1-2 and take the section test.


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http://www.icann.org/

Research the focus question for the next section.o What are the major components of a typical network?

Use the Internet to find an RFC describing private IP addressing. (Don’t expect students to read or understand the RFC at this point.) Where did you find it?

Go to http://standards.ieee.org/. o Search for Ethernet. What number(s) is/are associated with the Ethernet

standard? o Search for Token Ring. What number(s) is/are associated with the Token

Ring standard?


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http://standards.ieee.org/

Section 1-3: A Typical Computer Network

PreparationThis section introduces components used to build a typical computer network.

Exam Objectives 1.6 Identify the purpose, features, and functions of network components.2.4 Identify the OSI layers at which network components operate.3.4 Identify the main characteristics of network attached storage.

Vocabulary: client, server, resource, workstation, thin client, service software, protocol, network card, driver, client software, application, cable, repeater, hub, patch panel, bridge, switch, router, gateway

Focus Question: What are the major components of a typical network?

TimeAbout 1 hour


Network Interface Card (NIC) - A device inserted into a slot in a computer that allows it to connect to the network.

Network Implementation Network Attached Storage (NAS) - Another name for a file server. Offers storage

space to clients. NAS differs from a storage area network (SAN) in that a SAN offers high-speed data storage and retrieval to servers only.

Lecture Tips Start with the focus question. Do students have any questions about the material

they have studied? Introduce typical computer network components.

o Resources, servers, clients, connectivity devices. Discuss network resources and servers.

o Service software.o Protocol software.o Network card and driver.o Explain the difference between:

External server devices. External server devices including resources.

NAS – another name for a file server. Internal server devices.

Discuss client computers.o Applications.


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o Client software.o Protocol software.o Network card and driver.

Discuss network communication between two devices. o Explain how the network communication takes place with respect to the

OSI model. Use a diagram of the OSI layers on two computers. Show how data

passes down the OSI layers on the first computer, over the physical connection, and up the OSI layers on the second computer.

o Explain how the network communication can be passed through connectivity devices.

Stress the fact that a connectivity device operates at specific layer(s) of the OSI model. Students need to be able to associate devices with layers for the certification exam.

Discuss connectivity devices.o Physical layer .

Cable Repeater Hub (passive and active) Patch panel

o Data link layer. Bridge Switch

o Network layer. Router

o Various layers. Gateway


Write layers and devices on slips of paper and put them in a box. Have each student retrieve a card and identify the layer associated with the device or one device associated with the layer.

The following idea would make a nice pop quiz for the next class period. o Give students a list of devices and have them identify the layers at which

the devices workComputer Lab Activity

If you can, take a tour of a wiring closet and point out cables, patch panels, hubs, routers, etc.


Homework Suggestions Read Section 1-3 and take the section test.


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Research the focus question for the next section.o How are networks classified, and what types of services do they typically

provide? Read a few resources from Cisco. (You may want to skim these and reread after

completing Module 2.)o White Paper: Layer 3 Switching Demystified.

http://www.cisco.com/warp/public/cc/so/neso/lnso/cpso/l3c85_wp.htm o LAN Switching and VLANS.

http://www.cisco.com/univercd/cc/td/doc/cisintwk/ito_doc/lanswtch.htm#xtocid1

o Internetworking Technology Handbook. http://www.cisco.com/univercd/cc/td/doc/cisintwk/ito_doc/ is a great source for introductions to many networking topics.


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http://www.cisco.com/univercd/cc/td/doc/cisintwk/ito_doc/



http://www.cisco.com/warp/public/cc/so/neso/lnso/cpso/l3c85_wp.htm

Section 1-4: Varieties of Computer Networks

PreparationThis section introduces some of the major factors that influence network type, such as network size and network standards.

Exam Objectives 1.6 Identify the purpose, features, and functions of network components.2.11 Identify the basic characteristics of WAN technologies.2.12 Define the function of remote access protocols and services.

Vocabulary: LAN, MAN, WAN, peer-to-peer, server-based, protocol suite, file server, web server, print server, mail server, fax server, application server, database server, remote access server, directory server, share level security, user level security, password protected shares, authentication, network operating system

Focus Question: How are networks classified, and what types of services do they typically provide?

TimeAbout 1 hour

Network+ Exam FocusRemote Access Protocols

ICA - A protocol developed by Citrix, which allows a user to remotely control an application (such as a word processor) on a server. The application remains on the server and the interface is presented to the user.


they have studied? Networks can be classified by size and scope. Explain each concept. How does

your network fit into these categories?o LANo MANo WAN

Briefly mention LAN and WAN standards. These are covered in detail later in the course, so at this point simply mention that they exist.

o LAN technologies. Ethernet, Wi-Fi, Token Ring, FDDI. What does your network use?

o WAN technologies.


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PSTN, T1/E1 or T3/E3, SONet, SDH, ISDN, DSL, DOCSIS, Frame Relay, ATM.

What does your network use? What do students use to connect to the Internet from home?

Briefly mention protocol suites. These are covered in detail later in the course, so at this point simply mention that they exist.

o Define protocol suite/stack.o TCP/IP, IPX/SPX, NetBIOS/NetBEUI, AppleTalk, SNA, DNA, XNS,

VINES. Discuss client/service roles.

o Peer-to-peer networks.o Server-base networks (client/server networks).o What does your network use?

Networks provide services and resources. Discuss common services. Whenever possible, use examples from your own network environment. Do students use any of these services at school? What types of servers are providing these resources?

o Fileo Web o Printo Mailo Faxo Applicationo Databaseo Directoryo Remote accesso ICA

Developed by Citrix. Allows a user to remotely control an application (such as a word

processor) on a server. The application remains on the server and the interface is presented

to the user. Discuss security models. Use your own network as an example.

o Share level security. Password protected shares.

o User level security. Authentication.

o What type of security does your network use? How do students access resources?

o Discuss vendors and network operating systems.o Define network operating system.o Peer-to-peer with share-level security.

Microsoft Windows 9x (95, 98, or ME), Microsoft Windows 3.11 for Workgroups, Apple Macintosh OS, IBM OS/2 Warp Client, Artisoft LANtastic.

o Peer-to-peer with user-level security.


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Microsoft Windows NT Workstation, 2000 Professional, XP Home, XP Professional, UNIX.

o Server-based with user-level security. Microsoft Windows NT Server, 2000 Server, or .NET Server,

Novell NetWare, UNIX, AppleShare IP, Apple Macintosh OS Server, IBM OS/2 Warp Server, Banyan VINES, IBM LAN Server, Microsoft LAN Manager.


Log on to the network as a group. Discuss the logon screen and user vs. share level security. What type of security are you using? How do you know? Do the interfaces and operating system give you any indication of the type of security?

Use My Network Places (Network Neighborhood) to browse your computer network.

o Identify servers and discuss the services provided by each server. o Identify client computers. Are any of them participating in a peer-to-peer

network?



o What are the functions of the application layer of the OSI model? On a Windows 2000 Professional computer, right-click My Computer, then click

Manage. Browse to System Tools > Local Users and Groups > Users. What user accounts exist? Does this computer use share or user level security?

On a Windows 9x/Me computer, logon with a user name. Then logon again with a different user name. Log on again, but this time cancel the logon dialog box so that no user name is entered. Are these actual user accounts? Do they control your ability to use the computer? What are they for?


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Section 2-1: The OSI Application Layer

PreparationThe Application layer of the OSI model (Layer 7) describes how network clients learn about and use network services. This section discusses concepts related to the Application layer.

Exam Objectives 2.2 Identify the seven layers of the OSI model and their functions.

Vocabulary: service advertisement, active service advertisement, passive service advertisement, active client advertisement, passive client advertisement, service protocols

Focus Question: What are the functions of the application layer of the OSI model?

TimeAbout 1 hour

Network+ Exam FocusOSI Model

The Application layer provides an interface to the software that allows programs to use network services. The term application does not refer to a specific program, such as a word processor.


they have studied? The Application layer provides an interface to the software that allows programs

to use network services. o The term application does not refer to a specific program, such as a word

processor; this is a common misunderstanding.o Example: You are running Word and try to open a file stored on a file

server and the request for the file is transferred to the network by the application layer.

Briefly discuss service advertisement.o Active service advertisement.o Passive service advertisement.o Active client advertisement.o Passive client advertisement.

Discuss service protocols.o Remind students of major services: file, print, web, mail, fax, application,

database, directory, remote access.


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o There are protocols to support each of these services. A few examples that students may recognize:

HTTP supports transfer of web files between web servers and web clients.

SMTP allows a client to send mail. POP3 allows a client to receive mail.

What protocol does your network use for its directory service?


Explore a few service protocols. (Check sites to make sure they are available before class.)

o Use a browser to open http://www.microsoft.com and an ftp site. Point out the http and ftp protocols. They tell the browser which service protocol you are using.

o Open a mail client such as Outlook Express. Open the properties for a mail account and point out the POP, IMAP, and SMTP server configuration parameters.



o What are the functions of the presentation layer of the OSI model? Research the following question. Novell’s IPX/SPX protocol suite contains the

Service Advertisement Protocol (SAP). What type of advertisement technique does it use?


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http://www.microsoft.com/

Section 2-2: The OSI Presentation Layer

PreparationThe Presentation layer of the OSI model (Layer 6) describes how information is translated into an appropriate format to be transmitted over a network. This section discusses concepts related to the Presentation layer.

Before class, prepare the lecture activity.


Vocabulary: data encryption, data compression, symmetric encryption, secret key encryption, session key, asymmetric encryption, public key, private key, digital signature, digital envelope, signing, sealing

Focus Question: What are the functions of the presentation layer of the OSI model?

TimeAbout 1 hour


The Presentation layer acts as a translator between the application and the network. It formats data in a fashion that the network can use. It manages encryption and decryption. Presentation layer protocols also code and decode graphic and file format information.

The details of data encryption are not required for the Network+ exam. However, this topic comes up frequently in networking and computer security, so if you have time in your schedule, cover it.


they have studied? The Presentation layer acts as a translator between the application and the

network. It formats data in a fashion that the network can use. It manages encryption and decryption. Presentation layer protocols also code and decode graphic and file format information.

Discuss data encryption.o Symmetric encryption (secret key encryption).

One key is used to encrypt and decrypt. How do you exchange the key safely?

o Asymmetric encryption.


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Public key available to anyone. Private key kept secret. Digital signature used to sign a message – proof of identity . Digital envelope use to seal a message – keep the message secret.

o Use the lecture activity to help students understand this topic Discuss data compression.

o Communicate using less data.o Why do you want data compression when you make a 56K dial-up

connection to your ISP?o Why do we compress pictures posted on the web? What is a jpeg?


Make two identical keys. Label them both symmetric. Make two different keys. Label one private and the other public. You also need a piece of paper to represent a message and an envelope.

Symmetric encryption activity.o Give a symmetric key to one student. Explain that you are using your key

to encrypt your message. Then pass the message around the class. Who can read the message? What is the security issue with this technique? (How do you keep

the key secret – you need to get a copy of it to the person who is supposed to be able to read the message.)

Asymmetric encryption activity.o Put your public key on display in front of the class, and put your private

key in your pocket or desk. o Give the message paper to a student. Ask him or her to encrypt the

message with your public key. (Have student put the message in the envelope and lock it with the key.)

Why can the student encrypt the message? (Stress the point that your public key really is public and anyone can use it to encrypt something.)

o Pass the message around the class until it gets to you. Make a point of using your private key to open the envelope, but don’t let them see your private key. (It’s private!)

Who can read the message? What happens if your private key is compromised?

o Now demonstrate signing. Write your name on the message and use your private key to encrypt the signature.

Who can decrypt the signature? (Stress that they all have access to the public key.)

What is the point of signing the message? (You are the only one with your public key. If students can decrypt your signature, you must have sent the message.)

What happens if your private key is compromised? (Someone else can pretend to be you!)


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Computer Lab Activity Open or create a .bmp with Paint. Save the file using the .gif format. Open file

properties, or use Windows Explorer to determine the size of each file. How much was the file compressed when you saved it as a gif?



o What are the functions of the session layer of the OSI model? Use the Internet to investigate PGP – Pretty Good Privacy. Use the Internet to investigate encryption restrictions.

o Many countries restrict access to or export of encryption technologies. o Why? What types of restrictions can you find? Does the US have any

restrictions?


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Section 2-3: The OSI Session Layer

PreparationThe Session layer of the OSI model (Layer 5) describes how network clients and services establish, maintain, and terminate communication sessions with each other. This section discusses concepts related to the Session layer.

Get a couple small, soft balls for the lecture activity.


Vocabulary: connection-oriented communication, connectionless communication, session initialization, session maintenance, session termination

Focus Question: What are the functions of the session layer of the OSI model?

TimeAbout 1 hour


The Session layer of the OSI model is responsible for establishing and maintaining a connection between two nodes on the network. It describes how network clients and services establish, maintain, and terminate communication sessions with each other.


they have studied? The Session layer of the OSI model is responsible for establishing and

maintaining a connection between two nodes on the network. It describes how network clients and services establish, maintain, and terminate communication sessions with each other.

o The term “traffic cop” is often used to describe this layer Do the lecture activity. Discuss connection-oriented.

o Establish, maintain, terminate the connection.o Creates a session.o Reliable.o Creates overhead.

Discuss connectionless communication.o Does not verify existence of the other device.o Does not establish, maintain, or terminate the connection.


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o Less reliable.o Less overhead.

Discuss connection-oriented communication phases.o Session initialization (handshaking).o Session maintenance (data transmission phase).o Session termination (connection release).


You want to introduce the idea of making a connection before starting to communicate. Don’t give the students any warning. Simply toss a ball to someone in the class. Then tell another student that you are going to toss a ball his or her way, and throw the ball.

o If you want someone to catch the ball, which approach is more reliable? o If all you are worried about is throwing the ball, which approach is faster? o Which approach takes more effort on your part?



o What are the functions of the transport layer of the OSI model? Research TCP, which is a connection oriented protocol. How does TCP perform

handshaking?


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Section 2-4: The OSI Transport Layer

PreparationThe Transport layer of the OSI model (Layer 4) describes how messages are accurately delivered between network clients and services. This section discusses concepts related to the Transport layer.


Vocabulary: acknowledged communication, unacknowledged communication, error control, flow control, receive buffer, guaranteed rate flow control, stop-and-wait flow control, stop-and-go flow control, source-quench flow control, windowed flow control

Focus Question: What are the functions of the transport layer of the OSI model?

TimeAbout 1 hour


The Transport layer makes sure that messages are transferred from node A to node B reliably, without errors, and in the correct sequence. It manages flow control, the speed at which the recipient can accept data. If a message is too large for type of network, the Transport layer breaks the message into smaller pieces.


they have studied? The Transport layer makes sure that messages are transferred from node A to

node B reliably, without errors, and in the correct sequence. o It manages flow control, the speed at which the recipient can accept data.o If a message is too large for type of network, the Transport layer breaks

the message into smaller pieces. Example: Most Ethernet networks cannot use packets greater than

1500 bytes. Token Ring packets may be much larger (4,464 to 17,914 bytes). If a packet is too large when it passes from the Token Ring network to the Ethernet network, it has to be broken into smaller pieces.

Use the lecture activity to introduce acknowledged and unacknowledged communication.

Define acknowledged communication.o More overhead, accurate communication.


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o Example: TCP sends back messages in effect saying, “yes I got that data.” Define unacknowledged communication.

o Quick, but less accurate. Define error control.

o The sender should resend segments that are not received. Use the lecture activity to introduce the need for flow control. Define flow control.

o The sender should send data as rapidly as possible, without overwhelming the receiver.

o Explain receive buffers.o Briefly mention different approaches to flow control.

Guaranteed rate flow control. Stop-and-wait flow control. Stop-and-go flow control. Source-quench flow control. Windowed flow control.


Introduce acknowledged and unacknowledged communication. You need a few note cards to represent message segments.

o With two students, one student passes a card to another. The second student must say “I have card 1” before the first student can pass the next card.

o With two students, one student passes a card to another. The first student simply hands the cards over as fast as he can. The second student takes the cards, but doesn’t say anything, even if he drops a card. (Encourage the second student to drop a card.)

o Which technique is faster? Which is more accurate? Which generates more overhead?

Introduce the need for flow control. Draw a picture of a device with three buffers. Have another device rapidly send messages. What happens to the messages when the buffer is full?

AssessmentDid students participate?


o What are the functions of the network layer of the OSI model? Research TCP windowed flow control. How does it work?


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Section 2-5: The OSI Network Layer

PreparationThe Network layer of the OSI model (Layer 3) describes how data is routed to its destination. This section discusses basic concepts related to the Network layer.

Before class, configure your computer as a router. If you only have one NIC in the computer, use Add/Remove Hardware to install a second, fake NIC. Configure the IP settings for the NIC. Run the RRAS wizard and configure the computer as a router. Open Routing and Remote Access, right click the server, and select Enable Routing and Remote Access. Select the router option and follow the steps in the wizard. This sets up a routing table that you can demonstrate for the class.

If your computer is not normally configured as a router, after class, open Routing and Remote Access, right click the server, and select Disable Routing and Remote Access. Then use Device Manager to uninstall the fake NIC.

Exam Objectives 1.6 Identify the purpose, features, and functions of the following network

components:2.2 Identify the seven layers of the OSI model and their functions.2.4 Identify the OSI layers at which the following network components

operate:

Vocabulary: routable, non-routable, network address, point-to-point addressing, multi-point addressing, circuit switched, packet switched, source intelligent, router intelligent, packet intelligent, permanent circuits, on-demand circuits, store-and-forward data transfer, cut-through data transfer, route table, static routing table, dynamic routing table, unicast, multicast, broadcast

Focus Question: What are the functions of the network layer of the OSI model?

TimeAbout 1½ hours


The Network layer determines how data is routed from one part of the network to another. It also resolves the logical computer address (at the network layer) with the physical address of the network adapter (at the data link layer).

Network Components Router - A device that connects two or more segments of a network with

different IDs, and routes data between each segment.


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WAN Technologies Packet switching - A technology that allows packets from the same transmission

to take different routes to reach their destination. Circuit switching - A technology that creates a dedicated route or circuit between

two hosts on a WAN. All data moves along that route.


they have studied? The Network layer determines how data is routed from one part of the network to

another. It also resolves the logical computer address (at the network layer) with the physical address of the network adapter (at the data link layer).

o The network layer is responsible for routing data between subnetworks. It needs some type of addressing to identify computers, so it can decide where to send the messages.

Define network addressing. (Stress this topic.)o Discuss non-routable addressing.o Discuss routable addressing.o Draw a picture of a network with a router connecting a few segments.

Explain how non-routable and routable addressing works in this environment.

A non-routable address does not have segment IDs, so computers on different segments cannot communicate.

A routable address has segment IDs, so computers on different segments can communicate.

Explain the difference between point-to-point and multipoint addressing. (Stress this topic.)

o Point-to-point – send a message from one computer to another computer Unicast.

o Point-to-multicast – send a message from one computer to many Broadcast. Multicast.

Define routing.o What is the function of a router? (Stress this topic.)

It looks at the network address on a message and determines where to send the message.

o Very briefly discuss routing methods (This is not needed for the exam.) Circuit switched. Packet switched. Source intelligent. Router intelligent. Packet intelligent. Permanent circuits. On-demand circuits. Store-and-forward data transfer. Cut-through data transfer.


26

Discuss route tables.o This is how the router determines where to send the message.o Explain the difference between:

Static route tables. Use the route command on your computer to show your

routing table. Point out that you have two NICs in your computer.

o Type route /? for help. Administrator enters information manually. A lot of work in large environments.

Dynamic route tables. Routing protocols allow routers to communicate and build

the tables dynamically.


Use the route command to display the routing table on student computers.



o What are the functions of the data link layer of the OSI model? Use the Internet to investigate routers. Compare features and price of two

different routers.


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Section 2-6: The OSI Data Link Layer

PreparationThe Data Link layer of the OSI model (Layer 2) describes how one node prepares data to be sent to another node, and how multiple nodes coordinate the use of a single physical communication medium. This section discusses concepts related to the Data Link layer.

Before class create a handout listing about 5 to 10 different MAC addresses. Some addresses should be legitimate, some not.

Exam Objectives 1.6 Identify the purpose, features, and functions of the following network

components:2.1 Given an example, identify a MAC address.2.2 Identify the seven layers of the OSI model and their functions.2.4 Identify the OSI layers at which the following network components

operate:3.3 Identify the main characteristics of VLANs.

Vocabulary: framing, physical address, hardware address, MAC address, media access control, CSMA/CA, CSMA/CD, sequencing, time division, token passing, polling, bridge, switch, VLAN, broadcast domain

Focus Question: What are the functions of the data link layer of the OSI model?

TimeAbout 1 hour


The Data Link layer controls communication between the Network and Physical layers. If divides data from the Network layer into frames that can be transmitted on the Physical layer.

MAC Address A MAC address is a hardware address that uniquely identifies each host on a

network. Every NIC is hard-coded with a MAC address. It is comprised of six pairs of hexadecimal numbers. An example of a MAC address is: 00-A9-23-B3-55-FF.

Network Implementation Virtual LAN (VLAN) - A network of computers that behave as if they are

connected in a single segment even though they are physically located on different segments of a LAN.


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they have studied? The Data Link layer controls communication between the Network and Physical

layers. If divides data from the Network layer into frames that can be transmitted on the Physical layer.

Introduce framing.o Synchronizing sender and receiver.o Indicating the beginning and end of data transmission.o Stress physical addressing.

Physical address, hardware address, MAC address. Use ipconfig /all to show students the MAC address on the

instructor computer. Discuss media access control methods.

o CSMA. CSMA/CA. CSMA/CD.

o Sequencing. Time division. Token passing.

o Polling Discuss bridging, switching, and VLANs.

o Define broadcast domaino What happens when many computers share the same broadcast domain?

How does lots of broadcast traffic affect your network? o Explain how bridges work.o Explain how switches work.o Explain how VLANs work.


Pass out the handout and ask students to identify the legitimate MAC addresses. (You may want to use this as pop quiz during your next class period.)

Which of the following are legitimate MAC addresses? o A9-11-0C-B3-97-G1o JB-A9-45-AC-75-71o 12-56-63-88-4H-FFo 5D-92-E9-AA-52-FFo EF-C4-D4-7C-23-5A

Computer Lab Activity Use ipconfig /all (or winipcfg) to determine the MAC addresses of the lab

computers. Record results in lab notebooks.

AssessmentCheck lab notebooks. Check MAC address quiz.


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o What are the functions of the physical layer of the OSI model? Use the Internet to investigate switches. Compare features and price of two

different switches.


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Section 2-7: The OSI Physical Layer

PreparationThe Physical layer describes how nodes generate physical signals and how the signals are physically transmitted to other nodes. This section discusses concepts related to the Physical layer.

Before class, collect examples of cables for demonstration. Prepare diagrams to help explain the different network topologies. Create a handout containing pictures of different physical topologies.

Exam Objectives 1.1 Recognize the following logical or physical network topologies given a

schematic diagram or description:1.6 Identify the purpose, features, and functions of the following network

components:2.2 Identify the seven layers of the OSI model and their functions.2.4 Identify the OSI layers at which the following network components

operate:4.10 Given a troubleshooting scenario involving a network with a particular

physical topology and including a network diagram, identify the network area affected and the cause of the problem.

4.12 Given a network troubleshooting scenario involving a wiring/infrastructure problem, identify the cause of the problem.

Vocabulary: communication media, electromagnetic spectrum, coaxial cable, twisted pair cable, fiber-optic cable, point-to-point connection, multipoint connection, network topology, bus, ring, star, tree, mesh, cellular, physical topology, logical topology, hybrid topology, backbone, signaling, analog, digital, broadband, baseband

Focus Question: What are the functions of the physical layer of the OSI model?

TimeAbout 1½ hours


Physical layer controls the way data is actually sent over the physical medium. Network Topologies

Bus - Hosts are connected along a single trunk cable. Ring - Each host is connected to its neighbor until all hosts in the network form a

ring. Star - Hosts are connected to hubs or switches Mesh - Hosts have more than one connection to the network


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Network Components Transceiver - the device that converts signals from the computer to signals sent

over the wire, and vice versa. Today, most transceivers are built into NICs.


they have studied? Physical layer controls the way data is actually sent over the physical medium. It

addresses data coding and the physical components. o Data coding specifies items such as which signal actually represents a 0

and which represents a 1. Discuss communication media.

o Electromagnetic spectrum. Radio, microwave, infrared. Wireless communication. Do students use any wireless devices? Do they know which

technology is used? Remote control, handheld computer.

o Common types of cable. Coaxial cable. Twisted pair cable.

STP, UTP. Fiber-optic cable.

Multimode, single-mode. What type of wire is used for cable TV? A phone line? Do any students have home networks? What communication media

do they use? What does the school use?

Define network topology.o Explain the difference between point-to-point connections and multipoint

connections..o Present diagrams to help explain each of the different topologies

Bus. Ring.

Dual, counter-rotating rings. Star.

Stress the difference between physical topology and logical topology.

Physical star, logical bus. Physical star, logical ring.

Tree. Mesh.

Partial mesh, full mesh. Cellular. Hybrid topology. Backbone.


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Discuss signaling.o Network cards contain transceivers. They transmit and receiver signals

over the communication medium. For example, the NIC prepares the signal to be sent over the wire

and picks up signals from the wire. o Compare analog and digital signals. Draw pictures of signals.

Analog – continuous. Digital – discrete.

o Compare broadband and baseband signals.


Pass out example cables as you discuss different types of communication media. Pass out the topology handout and ask students to identify each topology. (You

may want to use this as a pop quiz during your next class period.)Computer Lab Activity

Diagram the physical cable layout of the lab.

AssessmentCheck lab notebooks. Check topology handouts.


o How do you use the OSI model in a real network? Draw a diagram of your home’s wiring infrastructure. This is most likely to be a

few cable TV lines, but it could also be a home network.


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Section 2-8: Multi-Layer Concepts

PreparationThis section discusses concepts related to multiple layers of the OSI model.

Before class, prepare to demonstrate bindings on the instructor computer. Install an additional protocol if there is only one installed.

Vocabulary: encapsulation, binding, multiplexing, addressing, resolution

Focus Question: How do you use the OSI model in a real network?

TimeAbout 1 hour

Network+ Exam FocusThis section does not directly address any exam objectives in detail. However, it does introduce a few concepts that are important to exam topics later in the course.


they have studied? Define logical communication channels.

o Stress the concept of encapsulation.o Example: A remote client uses a modem to connect an ISP and then

connects to his business network over the Internet. Messages sent to the business network are encapsulated so they can be sent over the Internet. Messages are unpackaged when they arrive at the business so they can be used on the business network.

Define multiplexing, binding, and addressing.o Stress the concept of binding. You can bind multiple protocols to a single

network card. o Show students how to view bindings on your computer.o Addressing occurs at multiple levels of the OSI model. Use an example:

www.school.edu corresponds to IP address 165.13.5.233. 165.13.5.233 corresponds to MAC address 00-06-47-3F-57-DA.

Discuss using the OSI model.o The OSI model is a theoretical model, not the real world. Actual network

protocol implementations do not correspond directly to the OSI model. Stress this fact, as it tends to cause confusion!

o Example: TCP/IP was developed independently of the OSI model. Protocols loosely correspond to levels of the OSI model, but they don’t match it exactly.


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http://www.school.edu/


What protocol or protocols are bound to the NIC on your lab computer? o On Windows 2000/XP computers, open Network and Dial-up connections.

On the Advanced menu, select Advanced settings.



o What types of cables and connectors are commonly used in networks? Use the Internet to investigate the OSI model. Can you find a protocol suite that

actually implements the OSI model (uses the model as it’s primary design guide)? Suppose you use your computer to connect to the web site www.microsoft.com.

Draw a diagram and explain the connection process between the your client computer and the web server. Explain the connection in terms of the OSI model.


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Section 3-1: Cables and Connectors

PreparationThis section introduces some common cable and connector standards used on computer networks.

Collect cables, connectors and tools to demonstrate. Collect RJ-45 connectors, UTP, and crimpers for the cable-making lab.

Exam Objectives 1.4 Recognize the following media connectors and/or describe their uses:1.5 Choose the appropriate media type and connectors to add a client to an

existing network. 3.7 Given a remote connectivity scenario, configure the connection.4.5 Given a wiring task, select the appropriate tool.

Vocabulary: American Wire Gauge Wires, RG coaxial cables, IBM Cables, EIA/TIA 568 UTP cables, EIA/TIA 568 STP cables, EIA/TIA 568 fiber-optic cables, D-shell connectors, RJ connectors, BNC connectors, fiber optic connectors, ST connector, SC connector, insulation displacement connectors (IDCs), IBM data connectors (IDCs), 568A wiring scheme, 568B wiring scheme, cutter, stripper, punch down tool, crimper, polisher, tester, time domain reflectometer, tone generator and locator, hardware loopback plug

Focus Question: What types of cables and connectors are commonly used in networks?

TimeAbout 1½ hours

Network+ Exam FocusConnectors

RJ-11 (modem). RJ-45 (10BaseT, 100BaseTX). AUI(10Base5, 100BaseTX). BNC. SC (FDDI, 100BaseFX). ST (FDDI, 100BaseFX).

Wiring Tools Crimper - A tool used to fasten connectors to wires. Media Tester - A tool that tests network cable to ensure conductivity through the

cable. It can also identify crossed wires and improper termination. Punch Down Tool - A tool that allows you to attach network and phone wire to a

punch down block.


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Tone Generator/Tone Locator - Also known as a fox and hound. A set of tools designed to help locate a single wire amidst many, for example, at a punch down block. The tone generator creates a signal and the tone locator detects the signal at the other end of the wire.

Optical Tester - A tool used to test fiber optic cable for continuity and signal attenuation.


they have studied? Discuss cable standards. Pass out examples.

o American Wire Gauge (AWG) Wires.o Radio Guide (RG) coaxial cables.o IBM cables.

Type 1, type 2, type 3, type 5, type 5J, type 6, type 9.o EIA/TIA 568 UTP cables.

CAT1, CAT2, CAT3, CAT4, CAT5, CAT5e.o EIA/TIA 568 STP cables.o EIA/TIA 568 fiber-optic cables.

Discuss Connectors. Pass out examples.o D-shell connectors.

Low density DB 15 –AUI.o RJ connectors.

RJ-11, RJ-45.o BNC connectors.o Fiber optic connectors.

ST connector, SC connector.o Insulation displacement connectors (punchdown blocks)o IBM data connectors.

Demonstrate common wiring schemes. o 568A wiring scheme – present a diagram.o 568B wiring scheme – present a diagram.

Demonstrate cabling tools. Collect as many tools as you can and demonstrate their use.

o Cutter.o Stripper.o Punch down tool.o Crimper.

Show students how to create a network cable.o Polisher.o Tester.o Time domain reflectometer (TDR).o Tone generator and locator.o Hardware loopback plug.


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Place a number of connectors in a box. Have each student retrieve a connector and identify it. If you don’t have enough hardware examples, use pictures.

Computer Lab Activity Use the 568A wiring scheme to make RJ-45 network cables. If you have a cable

tester, use it to test student cables. Document the procedure in lab notebooks. o After completing the lab, discuss the merits of purchasing pre-made

cables. A good electrical supply store (the kind used by electricians) will sell patch cables in many lengths. If you need a lot of cables, it may be cheaper to buy them than to make them yourself. (Don’t forget that your salary counts toward cost!)

o If you don’t have a cable tester, test the cable by connecting a lab computer to the wall jack or hub. You can tell if a cable works, although you can’t tell why one fails.

AssessmentWere students able to identify the connectors? Check cables and lab notebooks.


o How does an Ethernet network function? Make a crossover cable. (Use the Internet to find a wiring diagram for crossover

cables.) You need to purchase CAT5 cable for a new network. Where are you going to

buy it? How much does it cost? You need to purchase patch cables for a new network. Where are you going to

buy them? How much do they cost?


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Section 3-2: Ethernet (IEEE 802.3)

PreparationMost local area networks are based on Ethernet standards defined by IEEE's 802.3 committee. Ethernet is a broad name for a family of specific standards. This section covers the Ethernet standards.

Exam Objectives 1.2 Specify the main features of 802.2, 802.3, 802.5, 802.11b, and FDDI

networking technologies.1.3 Specify the characteristics (speed, length, topology, cable type, etc.) of

802.3 (Ethernet) standards, 10Base-T, 100Base-TX, 10Base-2, 10Base-5, 100Base-FX, and Gigabit Ethernet

1.4 Recognize media connectors and/or describe their uses.1.5 Choose the appropriate media type and connectors to add a client to an

existing network.1.6 Identify the purpose, features, and functions of network components.

Vocabulary: Ethernet, 10Base5, 10Base2, 10BaseT, 100BaseTX, 100BaseFX, 1000BaseT, 1000BaseLX, 1000BaseSX, 1000BaseCX, 802.3

Focus Question: How does an Ethernet network function?

TimeAbout 1½ hours

Network+ Exam FocusIEEE Standards

802.3 - EthernetEthernet Standard (802.3)

You can identify important details of Ethernet networks based on their names.Name Speed Length Topology Cable10Base2 10 Mbps 185 meters Bus Thinnet10Base5 10 Mbps 500 meters Bus Thicknet10BaseT 10 Mbps 100 meters Star CAT3 UTP100BaseTX 100 Mbps 100 meters Star CAT5 UTP1000BaseT 1000Mbps 100 meters Star CAT5 UTP

Connectors RJ-11 (modem) RJ-45 (10BaseT, 100BaseTX) AUI (10Base5, 100BaseTX) BNC SC (FDDI, 100BaseFX) ST (FDDI, 100BaseFX)


39


they have studied? Ethernet.

o Bus topology. Physical bus or logical star, physical bus.

o CSMA/CD media access method. 10Base5.

o Topology: Classic bus.o Trunk cable: RG-11 coaxial.o Drop cables: Four-pair (eight-wire) STP.o Connectors: AUI (DB-15).o Minimum distance between transceivers: 2.5 meters.o Maximum drop cable length: 50 meters.o Maximum trunk cable length before needing a repeater: 500 meters.o Maximum distance between any two end nodes: 2,460 meters.

Diameter limited by the Ethernet 5-4-3 rule.o Maximum nodes per cable segment: 100.o Maximum nodes per network: 300.

10Base2.o Topology: Classic bus.o Trunk cable: RG-58 A/U or RG-58 C/U coaxial.o Connectors: BNC/o Minimum distance between transceivers: 0.5 meters/o Maximum trunk cable length before needing a repeater: 185 meters/o Maximum distance between any two end nodes: 925 meters/

Diameter limited by the Ethernet 5-4-3 rule.o Maximum nodes per cable segment: 30.o Maximum nodes per network: 90.

10BaseT.o Topology: Physical star/Logical bus.o Cables: Category 3 or greater UTP.o Connectors: RJ-45.

Uses two wire pairs (four wires--positions 1, 2, 3, and 6).o Maximum cable segment length: 100 meters, which includes all cables

between a computer and hub.o Maximum cable segment lengths of 150 meters are possible with category

5 cable.o Maximum distance between two end nodes: 500 meters over a maximum

of four active hubs.o Maximum 2 nodes per cable segment.o Maximum 1024 nodes per network.

100BaseTX.o Topology: Physical star/Logical bus.


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o Cables: Category 5 or greater UTP or type 1A STP.o Connectors: RJ-45 for UTP cable, DB-9 for STP cable.

Uses two wire pairs (four wires--UTP positions 1, 2, 3, and 6, or STP pins 1, 5, 6, and 9).

o Maximum cable segment length: 100 meters, which includes all cables between a computer and hub.

o Maximum distance between two end nodes: 205 meters over a maximum of two active hubs.

o Maximum 2 nodes per cable segment.o Maximum 1024 nodes per network.

100BaseFX.o Topology: Physical star/Logical bus.o Cables: Multimode 62.5/125 fiber-optic .o Connectors: SC connectors recommended (other types of fiber-optic

connectors such as ST connectors are also permitted). Uses two fiber-optic strands (one receives data, the other sends

data).o Maximum cable segment length: 412 meters when operating in half-

duplex mode and 2000 meters when operating in full-duplex mode.o Maximum 2 nodes per cable segment.

1000BaseT.o Topology: Physical star/Logical bus.o Cables: Category 5E or greater UTP and type 1A STP.o Connectors: RJ-45 for UTP cable, DB-9 for STP cable.

Uses all four wire pairs (eight wires).o Maximum cable segment length: 100 meters, which includes all cables

between a computer and hub.o Maximum distance between two end nodes: 200 meters over a maximum

of one active hub.o Maximum 2 nodes per cable segment.

1000BaseLX.o Topology: Physical star/Logical bus.o Cables: Multimode 62.5/125 fiber-optic, Multimode 50/125 fiber-optic,

Single-mode fiber-optic.o Connectors: SC connectors recommended.

Uses two fiber-optic strands (one receives data, the other sends data).

o Wavelength: 1300 nanometers.o Maximum cable segment length: 316 meters (half-duplex), 550 meters

(multimode full-duplex), or 5000 (single mode full-duplex).o Maximum 2 nodes per cable segment.

1000BaseSX.o Topology: Physical star/Logical bus.o Cables: Multimode 62.5/125 fiber-optic, Multimode 50/125 fiber-optico Connectors: SC connectors recommended.


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Uses two fiber-optic strands (one receives data, the other sends data).

o Wavelength: 850 nanometers.o Distances: Maximum cable segment length: 275 meters (half-duplex), 550

meters (full-duplex). Using 50/125 fiber-optic cables increases the cable segment length further.

o Maximum 2 nodes per cable segment. 1000BaseCX.

o Topology: Physical star/Logical bus.o Cables: Twinaxial cable.o Connectors: Miniature DB-9 connectors, and 8-pin Fibre Channel Type 2

connectors.o Maximum cable segment length: 25 meters.o Maximum 2 nodes per cable segment.

Use the lecture activity to review standards.


Ask questions and have students respond verbally or record answers in lab notebooks.

Which standard(s) use fiber? Coaxial cable? Twisted pair? Which standard(s) use BNC connectors? RJ-45 connectors? SC connectors? What is the maximum cable length for 10Base2? 10Base5? 10BaseT? 100BaseT?

AssessmentCheck lab notebooks or verbal responses.


o Ethernet is the most popular LAN standard. Are they any other LAN standards?

If the school uses Ethernet, diagram a portion of the network. Identify hubs, switches, node lactations, and cable lengths.

You are installing a 10BaseT network. Price hubs, switches, and NICS. You are installing a 100BaseTX network. Price hubs, switches, and NICS. You are installing a 1000BaseT network. Price hubs, switches, and NICS.


42

Section 3-3: Other LAN Standards

PreparationMost local area networks (LANs) are based on Ethernet (IEEE 802.3), but other LAN standards also exist. This section explains the basic characteristics of some other LAN standards.

Exam Objectives 1.2 Specify the main features of 802.2, 802.3, 802.5, 802.11b, and FDDI

networking technologies.1.4 Recognize media connectors and/or describe their uses.1.5 Choose the appropriate media type and connectors to add a client to an

existing network. 1.6 Identify the purpose, features, and functions of network components.2.11 Identify the basic characteristics of WAN technologies.

Vocabulary: Wi-Fi, IEEE 802.11b, Token Ring IEEE 802.5, FDDI, 100VG-AnyLAN, IEEE 802.12, ARCNet, Token Bus, LocalTalk

Focus Question: Ethernet is the most popular LAN standard. Are they any other LAN standards?

TimeAbout 1½ hours

Network+ Exam FocusIEEE Standards

802.2 - Logical Link Control (LLC). 802.5 - Token Ring . 802.11b – Wireless. Token Ring - A less-common networking standard. It uses a ring topology. Most

Token Ring networks run at 4 or 16 Mbps. FDDI - A fiber optic networking standard that uses a dual ring topology for high

fault tolerance. It usually operates at 100 Mbps.Connectors

RJ-11 (modem). RJ-45 (10BaseT, 100BaseTX). AUI(10Base5, 100BaseTX). BNC. SC (FDDI, 100BaseFX). ST (FDDI, 100BaseFX).


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Network Components

Multi-station Access Unit (MAU) - Another name for a hub. The name usually denotes the type of hubs used on Token Ring Networks.

Wireless Access Point - A device that functions like a hub in a wireless network.


they have studied? 802.11b – wireless networking (WiFi).

o For the exam, stress the 802.11b number and wireless networking terms, not the term WiFi.

o Framing: Variable length frames.o Media Access: CSMA/CA.o Topology: Cellular.o Signaling: Direct sequence spread spectrum signaling. Data rate can reach

11 megabits per second. 802.5 – Token Ring.

o Framing: Variable length frames up to 18,000 bytes in length.o Media Access Control: Token passing. o Topology: Ring (hybrid of a ring and a physical star/logical ring).o Signaling: Baseband signaling, commonly at 4 or 16 megabits per second

(updated 100 and 1000 megabit versions also exist). All nodes must be configured to operate at the same speed.

o Cables: IBM STP, UTP, and fiber-optic cable.o Connectors:

DB-9 connectors to connect network cards to STP cables. IBM Data Connectors to connect STP cables to hubs or wall

outlets. RJ-45 for most UTP cables. Media filters to convert other connectors. SC or ST connectors for most fiber-optic cables.

FDDI – Fiber Distributed Data Interface.o Framing: Variable length frames up to 4500 bytes in length.o Media Access Control: Token passing .o Topology: Ring .

Dual attachment devices connect to dual counter rotating rings. Single attachment devices connect only to the primary ring.

o Signaling: Baseband signaling, 1300 nanometer light waves, 100 megabits per second.

o Cables: 62.5/125 multimode fiber recommended, single mode fiber.o Connectors: SC or ST recommended.

Briefly mention other standards.o 100VG-AnyLAN – IEEE 802.12 .o ARCNet – ANSI 878.1.


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o Token Bus – IEEE 802.4.o LocalTalk.

802.2 – Logical Link Control (LLC).o Data Link sublayer – standardizes how Network layer protocols

communicate with Data Link protocols.o Network layer and Data Link layer communicate via 802.2 protocol rather

than communicating with each other directly.o Network layer and Data Link layer do not need to know how to

communicate directly. Summarize with the lecture activity.


Quiz students on IEEE standards. (This could also be a pop quiz for your next class period.)

o 802.2, 802.3, 802.5, 802.11b, LLC, Ethernet, Token Ring, Wireless Call out a standard number and ask students to tell you the name. Call out a standard number and ask students to describe it. Call out a name and ask students for the standard number.

AssessmentCheck verbal responses to lab activity or quiz.


o How do you connect to a WAN? You are installing a Token Ring network. Investigate the cost. Price NICS and

MAUs. You are installing a wireless network. Investigate the cost. Price wireless

transceivers and access points. You are installing a FDDI network. Investigate the cost. Price hubs, cabling, and

NICs.


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Section 3-4: WAN Links

PreparationThis section introduces some technologies used to create WAN links.

Before class, make sure you understand your school’s WAN connections.

Exam Objectives 1.4 Recognize the following media connectors and/or describe their uses:1.5 Choose the appropriate media type and connectors to add a client to an

existing network. 1.6 Identify the purpose, features, and functions of the following network

components: 2.11 Identify the basic characteristics of the following WAN technologies.3.7 Given a remote connectivity scenario, configure the connection.4.2 Given a troubleshooting scenario involving a small office/home office

network failure, identify the cause of the failure.4.3 Given a troubleshooting scenario involving a remote connectivity

problem, identify the cause of the problem.

Vocabulary: WAN media, PSTN, T1, E1, SONET/SDH, ISDN, DSL, cable modems, wireless, satellite, frame relay, ATM, CSU/DSU

Focus Question: How do you connect to a WAN?

TimeAbout 1½ hours


Modem - A device that allows a computer to transmit data over telephone lines. CSU/DSU - Two devices that are packaged as a single unit. A CSU performs

protective and diagnostic functions for a telecommunications line. The DSU connects a terminal to a digital line.

WAN Technologies Packet switching - A technology that allows packets from the same transmission

to take different routes to reach their destination. Circuit switching - A technology that creates a dedicated route or circuit between

two hosts on a WAN. All data moves along that route. ISDN - A communication standard for sending digital data over regular telephone

wires. ISDN supports transfer speeds of 64 Kbps along a single communication channel (also known as a B channel). Most telephone companies offer two telephone lines: One for voice and one for data, or two for data for a maximum throughput of 128 Kbps.


46

FDDI - A fault-tolerant fiber optic networking standard (mentioned previously) FDDI networks are typically used as backbones for WANs.

ATM - A circuit-switching WAN technology that transfers data cells in a small, fixed size.

Frame Relay - A packet-switching protocol used for connecting hosts on a WAN. Mostly telephone companies use it.

Sonet - A very high speed standard for connecting fiber optic systems. The international equivalent of this standard is SDH.

T1 - A communication standard with a data rate of 1.544 Mbps. It is comprised of 24 - 64 Kbps channels. The international equivalent of T1 is E1, which has a transmission speed of 2 Mbps.

T3 - A communication standard with a data rate of 44.7 Mbps. It is comprised of 672 - 64 Kbps channels. It is the standard for the backbone of the Internet. The international equivalent of T3 is E3, which has a transmission speed of 34.4 Mbps.

OC-x - A standard for specifying the speed of fiber optic networks conforming to the SONET standard.


they have studied? WAN media.

o Your business is not likely to own the infrastructure for the WAN links. Instead, you typically lease it from someone else.

o What does your school do?o Power cable, phone cables, television cables, radio, microwave

Discuss WAN communication issues.o A WAN is often a network over a networko Transceivers must be appropriate for the mediumo WAN media might need to carry other signalso WAN media might support one direction only

Review circuit and packet switching.o Packet switching - A technology that allows packets from the same

transmission to take different routes to reach their destinationo Circuit switching - A technology that creates a dedicated route or circuit

between two hosts on a WAN. All data moves along that route. PSTN – the public switched telephone network.

o Point-to-point connections between modems (over the circuit switched network)

o Due to FCC regulations regarding power levels sent over communication lines, actual V.90 data rates do not exceed about 53 kbps.

o With V.90 modems, upstream speeds (from the client) remain 33.6 kbps.


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T1 and E1 PDH.o Data rate of 1.544 Mbps. It is comprised of 24 - 64 Kbps channels. The

international equivalent of T1 is E1, which has a transmission speed of 2 Mbps.

o Data rate of 44.7 Mbps. It is comprised of 672 - 64 Kbps channels. It is the standard for the backbone of the Internet. The international equivalent of T3 is E3, which has a transmission speed of 34.4 Mbps.

o Use a Channel Service Unit (CSU) and Data Service Unit (DSU) to connect a computer to one of these lines.

SONET/SDH.o A very high speed standard for connecting fiber optic systems. The

international equivalent of this standard is SDH.o OC-x is a standard for specifying the speed of fiber optic networks

conforming to the SONET standard. ISDN.

o For sending digital data over regular telephone wires. ISDN supports transfer speeds of 64 Kbps along a single communication channel (also known as a B channel).

o Most telephone companies offer two telephone lines: One for voice and one for data, or two for data for a maximum throughput of 128 Kbps.

DSL.o Some channels are dedicated to receiving downstream data, while others

are dedicated to sending upstream data.o Usually dedicates more channels to receiving downstream data.o Downstream Upstream

1.544 to 8.448 mbps 16 to 640 kbps Cable modems.

o Establish a WAN link over TV cables.o Downstream Upstream

31.2 mbps to 55.2 mbps 5 mbps to 10 mbpso Multiple nodes usually share channels, so the actual data rate per node can

be much slower than the preceding rateso Upstream communication is not always supported. You may use a

telephone connection to send upstream data to an Internet service provider.

Wireless and satellite.o Wireless WAN links

Frame relay.o A packet-switching protocol used for connecting hosts on a WAN. Mostly

telephone companies use it.o Switched Virtual Circuits (SVCs)--Virtual circuit between two frame relay

endpoints is established when needed and disconnected when no longer needed.


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o Permanent Virtual Circuits (PVCs)--Virtual circuit between two frame relay endpoints is established for permanent use.

ATMo A circuit-switching WAN technology that transfers data cells in a small,

fixed size.o Packet switching 53-byte (fixed length) cells at SONET/SDH speeds.o Supports switched virtual circuits and permanent virtual circuits.

FDDI.o Fault-tolerant fiber optic networking standard (mentioned previously)

FDDI networks are typically used as backbones for WANs.


As a group, discuss and diagram your school’s WAN connectivity. Record diagram in lab notebooks.



o What are the common network protocol suites? If you have a computer at home and connect to the Internet, diagram your home’s

WAN connectivity. You are shopping around for WAN connection options. Check on T1, DSL, cable

modem, and ISDN price and availability in your area.


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Section 4-1: Common Protocol Suites

PreparationThis section introduces several protocol suites.

Exam Objectives 2.3 Differentiate between network protocols in terms of routing, addressing

schemes, interoperability, and naming conventions.2.5 Define the purpose, function, and/or use of protocols within TCP/IP.2.6 Define the function of TCP/UDP ports. Identify well-known ports.2.8 Identify IP addresses and their default subnet masks. 2.9 Identify the purpose of subnetting and default gateways. 3.1 Identify the basic capabilities of server operating systems.3.2 Identify the basic capabilities of client workstations.3.7 Given a remote connectivity scenario, configure the connection.3.11 Given a network configuration, select the appropriate NIC and network

configuration settings.4.3 Given a troubleshooting scenario involving a remote connectivity

problem, identify the cause of the problem.4.4 Given specific parameters, configure a client to connect to the following

servers:4.11 Given a network troubleshooting scenario involving a client connectivity


Vocabulary: TCP/IP protocol suite, HTTP, HTTPS, SMTP, POP3, IMAP4, NNTP, NTP, telnet, LPD/LPR, FTP, TFPT, SSL, TCP, UDP, IP, IP address, subnet mask, default gateway, DNS, fully qualified domain name, URL, NetWare (IPX/SPX) protocol suite, NCP, NLMs, SPX, IPX, Windows/IBM (NetBIOS/NetBEUI) protocol suite, SMB, NetBIOS, NBF, NetBEUI, NetBIOS name, UNC, Macintosh (AppleTalk) protocol suite, AFP, ASP, ATP, ADSP, DDP, AppleTalk name, AppleTalk type, AppleTalk zone, SNA, DNA, XNS, VINES

Focus Question: What are the common network protocol suites?

TimeAbout 2 hours

Network+ Exam FocusNetwork Protocols

TCP/IP.o Routable protocol.o Protocol used on the Internet.o Uses classes and 32-bit IP addresses to identify hosts on the network.

IPX/SPX.


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o Novell NetWare protocol.o Routable protocol.o Uses MAC addresses to identify hosts on a network.o Different versions of IPX/SPX use different frame types. Hosts using

IPX/SPX must use the same frame type to communicate. NetBEUI.

o Non-routable protocol.o Fast, good for small Windows-only networks.o Uses computer names to identify hosts on a network.

AppleTalk.o Routable protocol.o Used primarily on older Macintosh computers (New Macintosh computers

use TCP/IP as their standard protocol).o Supports a maximum of 254 hosts.o Uses dynamically assigned ID numbers to identify hosts on a network.


they have studied? Introduce the Internet (TCP/IP) protocol suite.

o Introduce common protocols and explain their functions. HTTP. HTTPS. SMTP. POP3. IMAP4. NNTP. NTP. Telnet. LPD/LPR. FTP. TFPT. SSL. TCP. UDP. IP.

o Introduce the concept of an IP address. IP addressing is covered in more detail in the next section.

32 bits, 4 octets, decimal value between 0 and 255. IP addresses are routable. They have a network ID and a host ID. The subnet mask separates the host and network ID.

o IP addresses are routable. Default gateway – the router on your subnet. Run ipconfig on your computer and discuss your configuration

parameters.


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o Introduce DNS naming standards. Draw a diagram to show the hierarchical nature of DNS names. Where does your school’s DNS name fit in the tree? Define FQDN – fully qualified domain name. Add a couple computer names to your diagram and determine their

FQDNs. Trace the FQDN for a computer at your school.

o Discuss TCP/IP interoperability It is the protocol suite of the Internet. Default protocol for UNIX, Windows NT 4.0, 2000, and XP, and

NetWare 5.0. Non-proprietary and widely used.

o Discuss URLs Protocol://hostname or IPaddress:port/directory/filename ?

parameters. Present example URLs and discuss the syntax of each:

http://www.microsoft.com ftp://ftpserver.company.com http://192.168.1.15/data/sales/invoice.html

Introduce the NetWare (IPX/SPX) protocol suite.o Briefly introduce common protocols and discuss their functions.

NCP NLMs SPX IPX

o Introduce IPX addressing. 4-byte network address. Host ID address is the device’s MAC address.

o IPX addresses are routable.o NetWare servers use SAP to broadcast their names and the fact that they

are NetWare servers.o IPX/SPX is used primarily in NetWare environments. It is proprietary.

Introduce the Windows/IBM (NetBIOS/NetBEUI) protocol suite.o Briefly introduce common protocols and discuss their functions.

SMB NetBIOS NBF NetBEUI

o Introduce addressing. NetBIOS names are 15 characters plus an additional byte to

identify services. On a Windows 9x computer, the NetBIOS name is simply the

computer name. NetBIOS names are not hierarchical like DNS names.

o NetBIOS/NetBEUI addresses are not routable.


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http://192.168.1.15/data/sales/invoice.html

ftp://ftpserver.company.com/


o NetBIOS over TCP/IP provides a NetBIOS interface, but implements the networking using TCP/IP.

o Discuss UNCs. \\Servername\shared resource. Present examples and discuss syntax.

\\server1. \\server1\data. \\server1\data\sales. \\server1\data\sales\meeting10-25-01.doc.

Introduce the Macintosh (AppleTalk) protocol suite.o Briefly introduce common protocols and discuss their functions.

AFP ASP ATP ADSP DDP

o Introduce addressing. Phase 1 – Up to 254 nodes per segment, network IDs between 1

and 1024. Phase 2 – 16 bits for network ID, 8 bits for the node ID.

o AppleTalk is routable.o AppleTalk names have a name, type, and zone.o TCP/IP is more widely used on Macs.

Briefly mention other protocol suites.o SNAo DNAo XNSo VINES

Discuss configuring interoperability.o Computers need to be running the same protocols.o Load client software to allow the client to talk to the server.o Gateways can translate between protocols.


Close notebooks. Give each student the name of a protocol and ask him or her to explain the protocol function.

Present the diagram with the router. Ask the students to determine which computers can communicate with each other. You could do this as a group, hand out the diagram and use it as a quiz, or assign it as homework.

You may want to use this as a pop quiz for the next class period. Give the students a handout listing UNC paths and ask them to identify legitimate syntax.

o \\fileserver2.o \\fileserver2:80.o \\mail1\templates\expenses.xls.


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o \\mail1\templates\expenses.xls?december.Computer Lab Activity

Use ipconfig to determine the IP address, subnet mask, and default gateway of your computer. Record procedure and results in lab notebooks.

AssessmentWere students able to identify protocols? Were they able to determine which computers could communicate with each other? Check lab notebooks.


o How does IP addressing work? Hand out a DNS diagram with computer names at the bottom level. Ask students

to identify the FQDN for each computer. Substitute server and path names appropriate to your environment. Go to the Run

command and type the following UNC paths. What do you see? Explain how the UNC command syntax determines the results.

o \\server o \\server\sharename o \\server\sharename\folder o \\server\sharename\folder\file.txt

Identify the legitimate IP addresses in this list. If an IP address is not correct, explain the problem.

o 221.25.166.255o 15.0.0.5o 257.25.69.235o 12.15.222o 192.16.8.35o 199.301.10.171


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Section 4-2: TCP/IP

PreparationThis section explains the TCP/IP protocol suite in greater detail.

Exam Objectives 2.5 Define the purpose, function, and/or use of protocols within TCP/IP.2.6 Define the function of TCP/UDP ports. Identify well-known ports.2.7 Identify the purpose of network services.2.8 Identify IP addresses and their default subnet masks. 2.9 Identify the purpose of subnetting and default gateways. 2.10 Identify the differences between public vs. private networks. 3.9 Identify the purpose, benefits, and characteristics of using a proxy.3.11 Given a network configuration, select the appropriate NIC and network

configuration settings.4.1 Given a troubleshooting scenario, select the appropriate TCP/IP utility

from among the following:4.7 Given output from a diagnostic utility, identify the utility and interpret the

output.4.8 Given a scenario, predict the impact of modifying, adding, or removing

network services on network resources and users.

Vocabulary: IP Version 4 (IPv4), IPv4 classes, Class A, Class B, Class C, Class D, Class E, default subnet mask, Classless IP addressing, subnetting, DHCP, IP Version 6 (IPv6), cache, broadcast, local file, name server, host name resolution, Hosts file, DNS name servers, NetBIOS names resolution, Lmhosts File, NetBIOS Name Servers (WINS Servers), Address Resolution Protocol (ARP), private IP networks, NAT router, proxy server, ipconfig, Winipcfg, ifconfig, netstat, nbtstat, ping, tracert, nslookup, arp, Simple Network Management Protocol (SNMP)

Focus Question: How does IP addressing work?

TimeAbout 5 hours


Remember that Application-layer protocols that require guaranteed delivery, like FTP and Telnet, use TCP as their Transport protocol. Application-layer protocols that do not require guaranteed delivery, like TFTP use UDP.

The TCP/IP Protocol The following are common protocols used within the TCP/IP protocol stack: IP - Responsible for addressing and formatting packets.


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TCP - Guarantees the delivery of data and that packets are delivered in the same order in which they are sent.

UDP - Delivers packets directly over a network without error correction. It is used primarily for streaming data and video.

FTP - An Internet protocol used for transferring files. TFTP - Also a protocol for transferring files, but does not offer authentication or

guaranteed packet delivery. SMTP - A protocol for sending email messages between email servers. HTTP - The underlying Application-layer protocol of the Internet. When you type

in a URL, you are typing an HTTP command. HTTPS - The protocol used on secure web pages. It is used in conjunction with

SSL, an encryption protocol. POP3 - A protocol used to retrieve email from a server. IMAP4 - An email retrieval protocol like POP3, but with additional functionality,

like email text search and selective downloading. Telnet - A terminal emulation protocol that allows you to remotely connect to a

server. You can then enter commands and have them executed as if you were at the server.

ICMP - A protocol used for sending control, information or error messages. The ping command uses ICMP to check connection statuses.

ARP - A protocol used for finding a hosts MAC address by using its IP address NTP - A protocol used for synchronizing time clocks of all hosts on a network.

Common TCP/UDP Port Numbers to Know When a TCP/IP packet is sent to a computer, it needs not only a destination IP

address, but also a port number. A port number indicates the destination application of a packet.

15 Netstat 68 DHCP 123 NTP 1701 L2TP 21 FTP 69 TFTP 139 NetBIOS 1723 PPTP 23 Telnet 80 HTTP 143 IMAP 42 WINS 110 POP3 161 SNMP 53 DNS 119 NNTP 443 SSL

Network Services DHCP - Automatically assigns IP addresses to clients on a network. DNS - Resolves host names to IP addresses. Allows a client to contact another host

on a network using a name, which is easier to remember than an IP address. WINS - Resolves NetBIOS names to IP addresses. A Microsoft version of name

resolution implemented before DNS became the accepted standard. NAT - Network address translation. Allows a LAN to use one set of IP addresses

for internal traffic and a different set of addresses for external or Internet traffic. ICS - Internet connection sharing. A simple version of NAT that allows multiple

users to access the Internet via a single connection and a single IP address. SNMP - A set of protocols used for managing and monitoring large networks.

IP Addresses and Subnet Masks To identify hosts on a network, TCP/IP uses a 32-bit number called an IP address.

It is displayed in decimal format (for example, 172.18.125.0). To identify the network segment (or subnet) on which the host is located, TCP/IP uses a 32-bit


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number called a subnet mask. It is also displayed in decimal format (for example, 255.255.255.0).

IP addresses are separated into classes. Classes can be determined by the first number (also known as an octet) in the IP address. Each class has an associated default subnet mask as well.

Class First Octet Default Subnet Mask Class A 1 to 126 255.0.0.0 Class B 128 to 191 255.255.0.0 Class C 192 to 223 255.255.255.0

Default Gateway If a host resides on a network with multiple subnets, the host must be configured

with the IP address a default gateway. A default gateway is the IP address of a router. When a host needs to send a packet to another host on the network, it first checks the destination IP address to see if the host is located on the local subnet. If it is not, the host sends the packet to the default gateway, or the router. The router then forwards the packet to the appropriate destination.

Public and Private IP Addresses The Internet is a public network. IP addresses used on the Internet are public IP

addresses. Private networks that do not connect to the Internet or that use NAT to access the Internet use private IP addresses. Private IP addresses are reserved ranges of IP addresses that cannot be used on the Internet. There is one range for each class, as shown in the table below:

Class Private IP Address Range. Class A 10.0.0.1 - 10.255.255.254. Class B 172.16.0.1 - 172.31.255.254. Class C 192.168.0.1 - 192.168.255.254.

IPv6 Ipv6 is an updated, emerging version of the IP protocol. It addresses the current

system's shortage of IP addresses. An example of an IPv6 address is 2A50:0:0:0:8:800:200C:417A.

Network Implementation Firewall - A system implemented to prevent unauthorized communication in or

out of a private network. The most common type of firewall is the packet filter firewall, which filters packets based on port number.

Proxy server - A server that sits between a client and the Internet. It intercepts all requests from the network to the Internet to see if it can fulfill the requests itself. If not, it forwards the request to the Internet.

TCP/IP Utilities For the exam, you need to recognize the output of these utilities. Tracert - A utility that traces a packet from a local host to a remote host. The

output shows the routers through which a packet passes, as well as how long it takes to pass trough each router. Use tracert to locate a faulty router or where delays are occurring.

Ping - A utility that helps you determine whether another host is reachable from your computer. Use this utility when you are unable to reach a host and you want to find the scope of the problem.


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Arp - A utility that helps you detect invalid arp cache entries. The arp cache maps IP addresses to MAC addresses. If a computer on the local subnet has recently changed IP addresses, an incorrect arp cache entry will prevent you from contacting it.

Netstat - A utility that shows the current status of TCP/IP connections. Nbtstat - A utility that helps you troubleshoot NetBIOS naming problems. You

can also use the utility to remove or correct preloaded name cache entries. Ipconfig - A utility that displays current TCP/IP settings for your computer. Use

this utility to verify that the settings are correct and (in some cases) ensure that your computer is able to contact a DHCP server and receive IP addressing information.

Ifconfig - The Linux version of the Ipconfig utility Winipcfg - The Windows 95/98 version of the Ipconfig utility. Winipcfg uses the

standard Windows interface instead of a command-line interface. Nslookup - A command-prompt utility that allows you to send test queries to DNS

servers. These queries are useful for diagnosing and solving DNS name resolution problems, and for verifying that DNS records are correct.


they have studied? IP Version 4 (IPv4).

o TCP/IP addressing. 32 bits, 4 octets, decimal numbers between 0 and 255. Subnet mask separates network and host ID. Use a binary example to explain how the mask is used to determine

the network ID. Address 11000000 10101000 01000001 00010001Mask 11111111 11111111 11111111 00000000Subnet 11000000 10101000 01000001 --------Host -------- -------- -------- 00010001

o IPv4 classes.o Explain how to tell if an IP address is Class A, B, C, D or E. The first octet

is: A: 1-127 (First octet start with 0)

126 network IDs, up to 16,777,214 hosts B: 128-191 (First octet start with 10)

16,384 network IDs, up to 65,534 hosts C: 192-233 (First octet start with 110)

2,097,152 network IDs, up to 254 hosts D: 224-231 (First octet start with 1110)

268,435,455 multicast group ID E: 240-254 (First octet start with 1111)

Experimental useo Class A, B, and C networks have a default subnet mask.

A: 255.0.0.0


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B: 255.255.0.0 C: 255.255.255.0 Critical concept: To determine the class of an IP address, you

only need to know the IP address. Class is determined by looking at the value in the first octet. Each class does have a default subnet mask, however, the mask does not determine the class. This is a common point of confusion.

o Special addresses. Host ID’s all 0s: network ID. Network ID all 0s: specific host on the local network . Host ID all 1s: broadcast address for the local network. All 0s: default route in a routing table. 127.0.0.1: loopback address.

o Classless IP addressing. Ignores address classes to allocate IP addresses more efficiently. Show students how to convert between the CIDR notation and

dotted decimal notation for masks. /24 and 255.255.255.0

o IPv4 subnetting. Subnetting is the process of breaking down a large network into

smaller networks. Why do you need subnets?

Example: Suppose you are using a private Class B network ID, 172.16.0.0, and have 20,000 hosts.

What would the network be like if you didn’t break it into smaller pieces? Is it even possible to put 20,000 hosts on the same network segment?

Critical Concept. If you use the default subnet mask, you have one network segment. You don’t have any additional subnets! If you want to create subnets on your network, you need to create a custom subnet mask.

Example: Suppose you are using a private Class B network ID, 172.16.0.0, and have 20,000 hosts.

The default mask is 255.255.0.0. All hosts are on the same network.

When you create subnets, you simply use more bits than the default mask for your network.

Use the mask 255.255.255.0. Now you have 255 subnets, each of which can have up to 254 hosts.

o IPv4 host configuration. IP address, subnet mask, default gateway. Configure manually. Configure with DHCP (BootP).

IP Version 6 (IPv6).o 128 bits, 8 groups of 16 bits, expressed as hexadecimal numbers between

0 and FFFF.


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FEC0:98FE:8856:AAB1:1234:0098:FF72:AC32. Loopback address 0:0:0:0:0:0:0:1 or ::1.

o Autoconfiguration.o Better quality of service.o Security features.o Source intelligent routing.

Introduce name and address resolution methods.o Cache.o Broadcast.o Local file.o Name server.

Discuss host name resolution .o TCP/IP computer name/DNS name.o Hosts file.o DNS name servers.

Discuss NetBIOS names resolution.o Lmhosts File.o NetBIOS Name Servers (WINS Servers).

Discuss Address Resolution Protocol (ARP). Introduce private IP Networks.

o Some IP addresses are reserved for private networks and not routed on the Internet.

o A network may use private IP addressing internally, and have a few public IP addresses for connecting to the Internet.

o Private IPv4 Addresses. 10.0.0.0/8 – 10.0.0.0 to 10.255.255.255.255 172.16.0.0/12 – 172.16.0.0 to 172.31.255.255 192.168.0.0/24 – 192.168.0.0 to 192.168.255.255 169.254.0.0/16 – 169.254.0.0 to 169.254.255.255

Reserved for APIPA – the host automatically picks its own IP address.

o Private IPv6 Addresses. FEC0::/48 – binary beginning 1111 1110 11. FEC0::/64 – binary beginning 1111 1110 10.

Discuss network address translation (NAT) routers.o A network may use private IP addressing internally, and have a few public

IP addresses for connecting to the Internet.o NAT translates private addresses to public addresses so the network can

communicate on the Internet.


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Discuss proxy servers.o The client connects through a proxy server. o The proxy server can cache requests. o Proxy servers can also control Internet access, by limiting which clients

can connect to the internet through the proxy server. Demonstrate TCP/IP commands. Explain the syntax and use of each command.

o ipconfigo Winipcfgo ifconfigo netstato nbtstato pingo tracerto nslookupo arp

Discuss Simple Network Management Protocol (SNMP).


Identify legitimate IP addresses. o 169.254.2.68o 235.123.6.198o 128.256.201.33

Practice identifying the class of an IP address. o 45.16.7.8o 219.34.250.1o 293.6.17.89o 145.67.189.203o 121.45.6.253o 131.56.78.15

Given a scenario, what class address should you use? Will you use public or private IP addresses? Support your decision.

o You need to support 80,000 hosts. The network needs access to the Internet.

o You need to support 500 hosts. The network needs access to the Internet. o Your company is an ISP. You need to support connections for 150 Web

servers that your company will be hosting. Give a student a quick overview of what a service does. Ask the student to

identify the service.o DHCP/BootP, DNS, NAT, ICS, SNMP, WINS.

Computer Lab Activity Practice each of the following commands: Ipconfig, Winipcfg, or ifconfig.


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o Record your IP configuration. Ping your local IP address and the IP address of the default gateway. Then ping an

Internet site such as www.microsoft.com. o What do the results of each ping tell you about your connectivity?

Run tracert to your default gateway. Then run tracert to an Internet site such as www.microsoft.com.

o What do the results tell you? Run arp-a. Are they any entries in your arp cache? Ping a few computers in the

lab and a computer on the Internet. Run arp -a again. Are they any new entries in your arp cache?



o What can I do to secure my network? Practice identifying the class of an IP address.

o 159.16.129.234o 161.78.101.2o 78.91.78.206o 10.11.13.14o 67.126.36.56

Which if the following are valid host IP addresses. Why or why not? o 23.45.234.261o 64.64.64.66o 127.0.0.0o 10.255.255.255o 154.90.23.16

Run nslookup www.microsoft.com. Analyze the results. Run netstat on your computer. Then connect to a web site. Run netstat again. Did

anything change? Why? Run nbtstat –n. Analyze the results.


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Section 5-1: Security

PreparationThis section introduces important concepts related to security.

Exam Objectives 2.6 Define the function of TCP/UDP ports. Identify well-known ports.2.12 Define the function of the following remote access protocols and services.2.13 Identify the following security protocols and describe their purpose and

function:3.1 Identify the basic capabilities of the following server operating systems:3.2 Identify the basic capabilities of client workstations.3.7 Given a remote connectivity scenario, configure the connection.3.8 Identify the purpose, benefits, and characteristics of using a firewall. 3.10 Given a scenario, predict the impact of a particular security

implementation on network functionality.4.3 Given a troubleshooting scenario involving a remote connectivity problem

identify the cause of the problem.4.11 Given a network troubleshooting scenario involving a client connectivity


Vocabulary: physical security, user account, access rights, password policy, SSL, Kerberos, IPSec, PPP, PPPoE, PPTP, L2TP, firewall, TCP port, UDP port

Focus Question: What can I do to secure my network?

TimeAbout 2 hours

Network+ Exam FocusRemote Access Protocols

RAS - A protocol built in to Windows NT and 2000 that allows a remote user to log on to a LAN. The client also needs RAS client software, which is built into most versions of Windows.

PPP - A protocol used for connecting a computer to the Internet. Encapsulates TCP/IP packets and sends them to a server, which in turn puts them on the Internet. Supersedes the SLIP protocol.

Security Protocols IPSec - A set of protocols that supports secure exchange of TCP/IP packets. Used

with Virtual Private Networks, which allow a remote client to create a secure tunnel through an unsecure network (for example, the Internet) to a private network. The security for IPSec is provided by either PPTP or L2TP, which is a newer and more secure version of PPTP.

SSL - A protocol used in conjunction with HTTPS for enabling secure communication over the Internet.


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Kerberos - An authentication protocol that allows two hosts to verify each other over a public network like the Internet.


they have studied? Discuss low-level security.

o Communication medium and topology.o Physical access to equipment.

Introduce user accounts and access rights. Present an overview of access rights for the most common operating systems.

o Windows NT/2000/XP. Read, Read & Execute, Write, Modify, Full Control.

o NetWare. Read, Write, Erase, Create, Modify, File Scan, Access Control,

Supervisor.o UNIX.

Read, Write, Execute, for Owner, Group, Other.o Macintosh.

See Folders, See Files, Make Changes, Read/Write, Read Only, Write Only.

o Stress the nature of these access rights. They allow administrators to control what users can do to files on the network servers.

o Use your computer to demonstrate access rights to a folder. You are most likely to demonstrate this with Windows, but if you have access to additional systems, demonstrate those also.

o Introduce password policies. Discussion: What is your password policy? What happens if you

require really long passwords, but don’t train users about the need for strong security? Why do you want a password policy?

Do not allow blank passwords. Require passwords to be a minimum length. Require passwords to fit complexity rules. Require periodic password changes Do not allow reused passwords. Lock out accounts after a certain number of failed attempts. Only allow logon during certain hours. Don't use words in the dictionary. Don't use dates (such as birthdays or anniversaries). Use both uppercase and lowercase letters. Use non-alphabetic characters (such as numbers and symbols). Use mnemonics to create passwords.

Discuss security protocols.o Two main areas to protect: data on hard drives and data as it passes over

the network.


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Discussion: You are looking into security. What threats can you think of to data on hard drives? How could someone threaten data as it passes over the network?

o SSL - Secure sockets layer. Used with HTTPS to enable secure communication over the

Internet. Describe the process: Web client gets a certificate from a web

server. The certificate contains the server’s public key. The web client uses the public key to encrypt a session key and sends it to the server. The session key is used to keep the entire transaction secure.

Widely used when buying online – you want to keep your credit card number secure!

o Kerberos. Authentication protocol – allows two hosts to verify each other Windows 2000 Active Directory domains use Kerberos to

authenticate clients.o IPSec.

Secure exchange of TCP/IP packets – encrypts TCP/IP packets Note: One way to encrypt data is to use an application that

uses encryption. Web browsers and servers using HTTPS are a good example of this approach. The server and clients all know how to use SSL and HTTPS.

Not all applications know how to use encryption. IPSec encrypts at the Network layer, so data is encrypted no matter what applications you are using.

Used with Virtual Private Networks, which allow a remote client to create a secure tunnel through an unsecure network (for example, the Internet) to a private network.

The security for IPSec is provided by either PPTP or L2TP, which is a newer and more secure version of PPTP.

Discuss remote access protocols.o What is remote access? Discuss examples.

Connecting to an ISP. Connecting to a private RAS server. Connecting to a private RAS server over a VPN. Windows NT and 2000 provide RAS services that allow a remote

user to log on to a LAN. The client also needs RAS client software, which is built into most versions of Windows.

Demonstrate creating of different dial-up networking connections on instructor computer. Use these demonstrations to discuss basic remote access concepts. What do you need to configure on the client for different types of connections?

Create a dial-up connection to an ISP. Create a VPN connection that uses the dial-up ISP

connection.


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Create a dial-up connection to a RAS server.o PPP.

Remote access protocol used to dial-up to the Internet. Encapsulates TCP/IP packets and sends them to a server, which in

turn puts them on the Internet. Supersedes the SLIP protocol.

o PPPoE. Sends PPP packets over an Ethernet network, rather than a dial-up

connection.o PPTP.

For VPNs – remote client creates a tunnel to private network over a public network (Internet).

Encapsulates PPP packets to send over public network. Remote access server decrypts the packet and treats it like a PPP

packet.o L2TP.

May be used with IPSec for VPNs. Discuss firewalls.

o Discuss TCP and UDP ports. Port numbers identify a service. Example: 192.168.15.23:80 identifies the web (HTTP) service on

computer 192.168.15.23. When a client makes a request for a web page, it sends the request to port 80 on the web server.

15 Netstat. 21 File Transfer Protocol (FTP). 23 Telnet. 25 Simple Mail Transfer Protocol (SMTP). 53 Domain Name Service (DNS). 68 Dynamic Host Configuration Protocol (DHCP) client. 69 Trivial File Transfer Protocol (TFTP). 80 Hypertext Transfer Protocol (HTTP). 88 Kerberos. 110 Post Office Protocol, Version 3 (POP3). 119 Network News Transfer Protocol (NNTP). 123 Network Time Protocol (NTP). 137 Windows Internet Naming Service (WINS). 139 NetBIOS over TCP/IP (NBT). 143 Internet Message Access Protocol (IMAP). 161 Simple Network Management Protocol (SNMP). 443 Secure Sockets Layer (SSL). 515 Line Printer (LPR). 1701 Layer Two Tunneling Protocol (L2TP). 1723 Point-to-Point Tunneling Protocol (PPTP).

o Firewalls can be configured to allow messages through based on IP address and/or ports.


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If you are running Windows 200/XP, open WINNT\system32\drivers\etc\services. Do you recognize some of the ports?

Use the Make New Connection wizard to create a dial-up connection to the Internet.

o If student computers don’t have modems, install a fake modem at the beginning of this lab. The following steps are for a Windows 2000 Professional computer. Steps are similar for other Windows platforms.

o Run Add/Remove Hardware wizard > Add/Troubleshoot a device > Add a new device > No, I want to select the hardware from a list > Modems > Don’t detect my modem; I will select it from a list > (Standard Modem Types), select a model > Select a port.



o How can I protect my network from disasters? Use the Make New Connection wizard to create a dial-up connection to a private

network. Use the Make New Connection wizard to create a VPN connection. Create a password policy for the place you work. Defend your choices. How often

will the user be forced to change passwords? How many can they reuse? What is the minimum password length? Why are these choices appropriate for the environment you work in?


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Section 5-2: Fault Tolerance

PreparationThis section explains some basic concepts related to fault tolerance and disaster recovery.

Exam Objectives 3.5 Identify the purpose and characteristics of fault tolerance.3.6 Identify the purpose and characteristics of disaster recovery.

Vocabulary: UPS, RAID 0, disk striping, RAID 1, disk mirroring, disk duplexing, RAID 5, disk striping with parity, backup markers, normal backup, copy backup, incremental backup, differential backup, daily-copy backup

Focus Question: How can I protect my network from disasters?

TimeAbout 1½ hours

Network+ Exam FocusNetwork Implementation

Fault Tolerance - The ability of a network component to still function in the event of hardware or software failure. Primary fault tolerance strategies include redundant hard disks, backup power supplies and redundant network paths.

Disaster Recovery - The ability to restore data and communication after a network failure. The primary strategy for disaster recovery is backing up data and storing a copy off-site.


they have studied? Discuss the difference between fault-tolerance and disaster recover.

o Fault-tolerance – you can stress the network without it failing.o Disaster recover – you can recover the network after it fails.

Low-level redundancy.o Topology.o Duplicate servers.o UPS devices.

RAID.o RAID 0.

Disk striping. Blocks of data striped across two or more disks. Reduces fault-tolerance. Increases performance.


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o RAID 1. Disk mirroring, disk duplexing. Stores data on two disks.

o RAID 5. Disk striping with parity. Blocks of data striped across three or more disks. Parity data can be used to reconstruct data if one disk fails.

Discuss backup methods.o Backup markers.o Normal backup.o Copy backups.o Incremental backups.o Differential backups.o Daily-copy backups.o Normal combined with differential.o Normal combined with incremental.o Normal combined with differential and copy.

Demonstrate Windows backup to provide a concrete example of backup concepts. Show file attributes and point out the Archive attribute.


You need to create a backup plan for your network. Which backup method(s) backs up and marks files only if they have been changed since the last time they were backed up?

You need to create a backup plan for your network. Which backup method(s) backs up files only if they have been changed since the last full backup but does not mark them as being backed up?

You perform a full backup of your file server every Sunday night. The rest of the week you perform an incremental backup at 11:00 PM. The file server fails at 9:00 AM on Wednesday. How do you restore the server? How much data, if any, will you loose?

You perform a full backup of your file server every Sunday night. The rest of the week you perform a differential backup at 11:00 PM. The file server fails at 1:00 PM on Thursday. How do you restore the server? How much data, if any, will you loose?

Computer Lab Activity Use Windows Backup to back up a folder on your lab computer. (Have students

select a folder that is not too large.) Record procedure in lab notebooks.



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o What can you do to increase a network’s performance? Backup a file on your computer. Check the archive attribute. Next, change the

contents of the file. Check the archive attribute again. Back up My Documents and then restore the folder to a different location. Create a backup plan for your home computer. What is your backup device? Do

you plan to spend any money? How much will you back up? How often? Justify your decisions.


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Section 5-3: Performance

PreparationThis section explains some principles for optimizing your network's performance.

Vocabulary: performance, baseline, abnormal performance, trend, bottleneck

Focus Question: What can you do to increase a network’s performance?

TimeAbout 1½ hours

Network+ Exam FocusAlthough this section does not directly cover exam objectives, it does introduce tools that are widely used by network administrators.


they have studied? Discuss low-level performance issues.

o Network architecture.o Computer hardware.o Use your current network as an example. Are you running 10BaseT or

100BaseT? Do you use hubs or switches? What speed are they? Introduce network performance monitoring. Briefly discuss each tool.

o Windows Performance Monitor.o Windows Network Monitor.o NetWare MONITOR.NLM.o NetWare LANalyzer Agent and ManageWise Management Console.o SNMP.o Demonstrate one of your network monitoring tools. (This will depend on

your infrastructure, but if students are running Windows 2000 or XP, demonstrate Performance Monitor.)

Explain why you should create a baseline.o How to create a baseline.o Use it to detect abnormal performance.o Use it to detect a trend.o Use examples from your own network to discuss baseline performance.

What are the peak logon times? What are the peak web-surfing times? Are any of the servers hit really hard? Do they need to be upgraded? How can you tell?

o Discussion statement: A baseline is a good political tool.


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How do you convince the money people that the server really needs to be upgraded and that you are not just looking for cool new technology?

Discuss bottlenecks. o Define bottlenecks: a limiting component, a component that can’t

accommodate the current load placed on it. o Increate the rate at which the component operates.

Upgrade a 10 meg hub to a 100 meg switch.o Decrease the component’s workload.

Split an overloaded Ethernet segment into two segments (or replace a hub with a switch).

Remove unused services from a server. Add a CPU to a server.


Use Performance (System Monitor) to look at the performance of your computer. o Add counters.

Processor, % Processor Time. Memory, Available Bytes. Physical Disk, % Disk Time.

o Generate activity. Play a game, open some files, open a few large programs, etc.

o What happens to the counters as you generate activity?



o What kinds of tasks are required when you install a network? You manage an Ethernet network that uses 100MB hubs. There are 30 clients on

each network segment (subnet). You are thinking about replacing the hubs with 100 MB switches. What type of performance gains do you expect to see? How much will it cost?


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Section 6-1: Installation

PreparationNetwork installation involves four fundamental steps, which are explained in this section.

Before class, make a list of a few areas where your network could use improvement.

Exam Objectives 3.7 Given a remote connectivity scenario, configure the connection.

Vocabulary: network architecture, network service, network operating system, client operating system

Focus Question: What kinds of tasks are required when you install a network?

TimeAbout 1 hour

Network+ Exam FocusThis section does not directly address exam objectives.


they have studied? Discuss planning a network installation. Use your own network as an example.

o Find out about the existing network, plans, and standards. What are you using now?

o Choose a network architecture. If you could upgrade would you change your architecture, or just

the speed?o Decide which services the network will provide.

What do you use now? Is there anything you would like to add?o Choose a network operating system.

What OS do you use now? Do you plan to upgrade soon? What OS? Why?

o Choose client operating systems. What OS do you use now? Do you plan to upgrade soon? What

OS? Why?o Create network administration standards.

Do you have any defined standards? Who keeps track of them? How are they decided?

o Announce the installation schedule. Have you ever been involved in an upgrade or installation? Did

you keep to the schedule?


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Discuss installing cables and connectivity devices.o Spend some time on the 100BaseT installation. This standard is important

because it is the most common standard in use today. o Stress that the 100-meter cable limit includes all cables between the

computer and the hub. Cable from the patch panel to hub and from the computer to the wall jack counts toward the limit. Students often miss this concept.

Discuss installing servers.o Choose an appropriate physical environment.o Physically install the network card.o Connect the network cable.o Install the network operating system.o Install and configure the driver for the network interface card.o Install and configure network protocol software.o Install and configure additional network service software.o Example: You are installing a DNS server in a Windows 2000, 100BaseT

network. Where should you put the server? What kind of NIC should you

install? What type of cable and connectors will you use? What is the network OS? Will you need to install a driver for the NIC? Is the driver likely to be plug-and-play? What protocol needs to be installed? What service are you installing?

Discuss installing workstations.o Physically install the network card.o Connect the network cable.o Install the client operating system.o Install and configure the driver for the network interface card.o Install and configure network protocol software.o Install and configure network client software.o Example: You are installing a Windows 2000 Professional computer in a

Windows 2000 Active Directory domain, 100BaseT network. You just installed a DNS server on this same network.

What kind of NIC should you install? What type of cable and connectors will you use? What is the client OS? Will you need to install a driver for the NIC? Is the driver likely to be plug-and-play? What protocol needs to be installed? What client software needs to be installed to connect to a Windows 2000 network? Does this computer need to be configured to use the new DNS server? How do you configure it as a DNS client?


Present the list of desired network improvements. Have students divide into small groups and plan for network improvements. When students are ready, discuss group plans as a class.


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o What types of tasks are required to maintain a network? Plan a home network.


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Section 6-2: Maintenance

PreparationThis section introduces tasks you should regularly perform as maintenance tasks after a network is set up.

Vocabulary: monitoring, virus, patch, upgrade, documentation

Focus Question: What types of tasks are required to maintain a network?

TimeAbout 1 hour

Network+ Exam FocusThis section does not directly address exam objectives.


they have studied? Briefly mention monitoring. You reviewed a few tools in Section 5-3.

o Monitoring adds load, so monitor what you need to, but be careful not to monitor so much that performance degrades.

Discuss viruses.o Install antivirus software on servers and workstations.o Update software regularly.o Train users.o Use your environment as an example. What do you run on lab computers?

How often do you update antivirus software? Are you running antivirus software on your mail server? Do you scan for problem attachments?

Discuss software patches and upgrades.o Manufacturer’s web site.o Example: Demonstrate the Windows Update website, available on the start

menu or at http://windowsupdate.microsoft.com/. Discuss the need for good documentation.


Go to http://windowsupdate.microsoft.com/ and check to see if your computer needs any updates.

Run the antivirus software on lab computers. Scan your hard drives for viruses.



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http://windowsupdate.microsoft.com/

http://windowsupdate.microsoft.com/


o How do I begin to solve network problems? Check Windows Update for your home computer. Investigate three antivirus packages. Which one do you like best? Why?


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Section 6-3: Troubleshooting

PreparationThis section introduces techniques and tools that can help you troubleshoot.

Before class, prepare troubleshooting examples based on your own network and experience.

Exam Objectives 4.2 Given a troubleshooting scenario involving a small office/home office

network failure, identify the cause of the failure.4.3 Given a troubleshooting scenario involving a remote connectivity

problem, identify the cause of the problem.4.6 Given a network scenario, interpret visual indicators to determine the

nature of the problem.4.9 Given a network problem scenario, select an appropriate course of action

based on a general troubleshooting strategy. This strategy includes the steps of the general troubleshooting model.

4.10 Given a troubleshooting scenario involving a network with a particular physical topology and including a network diagram, identify the network area affected and the cause of the problem.

4.11 Given a network troubleshooting scenario involving a client connectivity problem, identify the cause of the problem.

4.12 Given a network troubleshooting scenario involving a wiring/infrastructure problem, identify the cause of the problem.

Vocabulary: power light, link light, activity light, error message, error log, performance monitor

Focus Question: How do I begin to solve network problems?

TimeAbout 1½ hours

Network+ Exam FocusTroubleshooting Hints

Remote Access - If you are having trouble connecting to a LAN from a remote location, make sure that your cables are properly connected, that the correct protocols are installed and that you have the proper permissions to access resources.

Link Lights - Use link lights to verify connectivity. When a link light is not lit, either the cable is bad or one of the devices on either side of the cable is not functioning properly.

Collision Lights - A collision occurs when two hosts on an Ethernet network send packets at exactly the same time. The result is an unreadable packet. If a


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collision light is on frequently on a hub, you either have too much traffic for the available bandwidth or you may have a malfunctioning NIC in one of the computers connected to the hub.

Network Wiring - Network faults differ, depending on the topology used. For example, if a user disconnects his computer from a bus network, the entire segment will stop working. Similar problems can happen with ring networks. Also, if cables are extended beyond their recommended maximum distances or the wrong cable grade is used, the network will not necessarily cease to function. However, high data error rates will occur and some hosts may not be able to connect.

User Rights and Permissions - Rights and permissions are implemented on a network to ensure the safety of sensitive information but also easy access to resources required by many users. If a user is having difficulty accessing a certain resource on the network, make sure that the user has access rights to that resource.

Logging on to a Network - All secure network operating systems require a username and password to log on. If you are having difficulty logging on, remember that passwords are case-sensitive. Make sure that Caps Lock is not on. Also, if you have tried to log on unsuccessfully many times, your account may have been locked out.


they have studied? Discuss the general troubleshooting model.

o Step 1: Establish the Symptoms.o Step 2: Identify the Affected Area.o Step 3: Establish What has Changed.o Step 4: Select the Most Probable Cause.o Step 5: Implement a Solution.o Step 6: Test the Result.o Step 7: Recognize the Potential Effects of the Solution.o Step 8: Document the Solution.

Present troubleshooting examples. Use the model as a guide for solving the problems.

o Example 1: Draw a diagram with four computers, two on subnet 192.168.1.x/24 and two on subnet 192.168.2.x/24. The subnets are connected by a router. Router port IP addresses are 192.168.1.1 and 192.168.2.1. Label the IP address, subnet mask, and default gateway for each client. Label the default gateway of one of the clients on subnet 1 incorrectly.

One of the clients on subnet 1 can’t communicate with clients on subnet 2. The other client on this subnet can communicate with clients on subnet 2.


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Clients are supposed to be configured with DHCP, but upon inspection, you discover the IP configuration for the problem client has been set manually.

o Example 2: You run a 100BaseT, Windows 2000 network. Clients run Windows 2000 Professional or Windows XP. Gina calls to say that she can’t connect to the file server. What do you do first?

In this case, the file server is down. Walk through the problem. o Example 3: You run a 100BaseT, Windows 2000 network. Clients run

Windows 2000 Professional or Windows XP. Mark calls to say that he can’t connect to the file server. What do you do first?

In this case, there is a router connecting two subnets. The server is on subnet 1; Mark is on subnet 2. The router is down, so no one on subnet 2 can connect to the server. Walk through the problem.

o Example 4: You are having trouble connecting to a Windows 2000 remote access server. The message indicates you don’t have permission to log on.

You are having trouble connecting to a LAN from a remote location.

Make sure that your cables are properly connected. Make sure correct protocols are installed. Make sure you have the proper permissions to access

resources. (In this example, Windows 2000 domains require that the user account be given permission to dial-up to the remote access server. You don’t have that permission.)

o Present your own examples. Discuss troubleshooting indicators and tools. Demonstrate anything you can.

o Power lights.o Link lights.

Use link lights to verify connectivity. When a link light is not lit, either the cable is bad or one of the devices on either side of the cable is not functioning properly.

Look at the link lights on the classroom computers. If there is a switch or hub in the room, take a look at it too.

o Activity lights. Collision Lights - A collision occurs when two hosts on an

Ethernet network send packets at exactly the same time. The result is an unreadable packet. If a collision light is on frequently on a hub, you either have too much traffic for the available bandwidth or you may have a malfunctioning NIC in one of the computers connected to the hub.

Look at the activity lights on the classroom computers. If there is a switch or hub in the room, take a look at it too.

o Error messages. Try to log on with the wrong password. What is the error message? User Rights and Permissions - Rights and permissions are

implemented on a network to ensure the safety of sensitive


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information but also easy access to resources required by many users. If a user is having difficulty accessing a certain resource on the network, make sure that the user has access rights to that resource.

Logging on to a Network - All secure network operating systems require a username and password to log on. If you are having difficulty logging on, remember that passwords are case-sensitive. Make sure that Caps Lock is not on. Also, if you have tried to log on unsuccessfully many times, your account may have been locked out.

o Error logs. Open Event Viewer on a Windows NT/2000/XP computer at take a

look at the error log.o Environmental factors.

Dust, dirt, heat, controlled access.o Performance monitors.

Remind students of the Performance tool in Windows 2000.

Lab/ActivityLecture ActivityComputer Lab Activity

Unplug the network cable for your lab computer. Take a look at the link lights on the NIC. If possible, look at the lights on the classroom hub or switch.


Homework Suggestions Read Section 6-3 and take the section test. Research the focus question for the next section. Find a STOP message in Event View on a Windows 2000 computer. Research the

cause of the error and the solution to the problem. http://support.microsoft.com is a good place to look for more information on STOP messages.


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http://support.microsoft.com/

Appendix A: Network+ Exam Objectives

To find instruction for a particular exam objective, locate the objective below. Then note the section(s) in the course you need to study. References to the course use the format [module #]-[section #].

Exam N10-002, CompTIA's Network+ Certification

1.0. Media and Topologies

Objectives TestOut for Network+ 1.1 Recognize the following logical or physical network topologies given a 2-7

schematic diagram or description:

Star/hierarchical Bus Mesh Ring Wireless

1.2 Specify the main features of 802.2 (LLC), 802.3 (Ethernet), 802.5 3-2, 3-3(Token Ring), 802.11b (wireless), and FDDI networking technologies,including:

Speed Access method Topology Media

1.3 Specify the characteristics (e.g., speed, length, topology, cable type, 3-2etc.) of the following:

802.3 (Ethernet) standards 10Base-T 100Base-TX 10Base-2 10Base-5 100Base-FX Gigabit Ethernet

1.4 Recognize the following media connectors and/or describe their 3-1 to 3-4


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uses:

RJ-11 RJ-45 AUI BNC ST SC

1.5 Choose the appropriate media type and connectors to add a client to 3-1 to 3-4an existing network.

1.6 Identify the purpose, features, and functions of the following 1-3, 1-4, network components: 2-5 to 2-7,

3-2 to 3-4 Hubs Switches Bridges Routers Gateways CSU/DSU Network interface cards/ISDN adapters/System Area Network cards Wireless access points

2.0. Protocols and StandardsObjectives TestOut for Network+ 2.1 Given an example, identify a MAC address. 2-6

2.2 Identify the seven layers of the OSI model and their functions. 1-1, 2-1 to 2-7

2.3 Differentiate between the following network protocols in terms of 4-1routing, addressing schemes, interoperability, and naming conventions:

TCP/IP IPX/SPX NetBEUI AppleTalk

2.4 Identify the OSI layers at which the following network 1-3, 2-5 to 2-7components operate:

Hubs Switches Bridges Routers Network Interface Cards


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2.5 Define the purpose, function, and/or use of the following 4-1, 4-2protocols within TCP/IP:

IP TCP UDP FTP TFTP SMTP HTTP HTTPS POP3/IMAP4 Telnet ICMP ARP NTP

2.6 Define the function of TCP/UDP ports. Identify well-known 4-1, 4-2, 5-1ports.

2.7 Identify the purpose of the following network services: 4-2

DHCP/BootP DNS NAT/ICS WINS SNMP

2.8 Identify IP addresses (IPv4, IPv6) and their default subnet masks. 4-1, 4-2

2.9 Identify the purpose of subnetting and default gateways. 4-1, 4-2

2.10 Identify the differences between public vs. private networks. 4-2

2.11 Identify the basic characteristics (e.g., speed, capacity, media) 1-4, 3-3, 3-4of the following WAN technologies.

Packet switching vs. circuit switching ISDN FDDI ATM Frame Relay SONET/SDH T1/E1 T3/E3


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OC-x

2.12 Define the function of the following remote access protocols 1-4, 5-1and services.

RAS PPP PPTP ICA

2.13 Identify the following security protocols and describe their purpose and 5-1function:

IPsec L2TP SSL Kerberos

3.0. Network ImplementationObjectives TestOut for Network+ 3.1 Identify the basic capabilities (i.e., client support, interoperability, 4-1, 5-1

authentication, file and print services, application support, and security)of the following server operating systems:

UNIX/Linux NetWare Windows Macintosh

3.2 Identify the basic capabilities of client workstations (i.e., client 4-1, 5-1connectivity, local security mechanisms, and authentication).

3.3 Identify the main characteristics of VLANs. 2-6

3.4 Identify the main characteristics of network attached storage. 1-3

3.5 Identify the purpose and characteristics of fault tolerance. 1-1, 5-2

3.6 Identify the purpose and characteristics of disaster recovery. 1-1, 5-2

3.7 Given a remote connectivity scenario (e.g., IP, IPX, dial-up, 3-1, 3-4, 4-1, PPPoE, authentication, physical connectivity, etc.), configure 5-1, 6-1the connection.

3.8 Identify the purpose, benefits, and characteristics of using a firewall. 5-1


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3.9 Identify the purpose, benefits, and characteristics of using a proxy. 4-2

3.10 Given a scenario, predict the impact of a particular security implementation 5-1on network functionality (e.g., blocking port numbers, encryption, etc.).

3.11 Given a network configuration, select the appropriate NIC and network 4-1, 4-2configuration settings (DHCP, DNS, WINS, protocols, NetBIOS/host name, etc.).

4.0. Network Support Objectives TestOut for Network+ 4.1 Given a troubleshooting scenario, select the appropriate TCP/IP utility 4-2

from among the following:

tracert ping arp netstat nbtstat ipconfig/ifconfig winipcfg nslookup

4.2 Given a troubleshooting scenario involving a small office/home 3-4, 6-3office network failure (e.g., xDSL, cable, home satellite, wireless,POTS), identify the cause of the failure.

4.3 Given a troubleshooting scenario involving a remote connectivity 3-4, 4-1, problem (e.g., authentication failure, protocol configuration, 5-1, 6-3physical connectivity) identify the cause of the problem.

4.4 Given specific parameters, configure a client to connect to the following 4-1servers:

UNIX/Linux NetWare Windows Macintosh

4.5 Given a wiring task, select the appropriate tool (e.g., wire crimper, 3-1media tester/certifier, punch down tool, tone generator, optical tester, etc.).

4.6 Given a network scenario interpret visual indicators (e.g., link lights, 6-3collision lights, etc.) to determine the nature of the problem.


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4.7 Given output from a diagnostic utility (e.g., tracert, ping, ipconfig, etc.), 4-2identify the utility and interpret the output.

4.8 Given a scenario, predict the impact of modifying, adding, or removing 4-2network services (e.g., DHCP, DNS, WINS, etc.) on network resourcesand users.

4.9 Given a network problem scenario, select an appropriate course of 6-3action based on a general troubleshooting strategy. This strategy includesthe following steps:

1. Establish the symptoms2. Identify the affected area3. Establish what has changed4. Select the most probable cause5. Implement a solution6. Test the result7. Recognize the potential effects of the solution8. Document the solution

4.10 Given a troubleshooting scenario involving a network with a particular 2-7, 6-3physical topology (i.e., bus, star/hierarchical, mesh, ring, and wireless)and including a network diagram, identify the network area affected andthe cause of the problem.

4.11 Given a network troubleshooting scenario involving a client 4-1, 5-1, 6-3 connectivity problem (e.g., incorrect protocol/client software/authenticationconfiguration, or insufficient rights/permissions), identify the cause ofthe problem.

4.12 Given a network troubleshooting scenario involving a 2-7, 6-3wiring/infrastructure problem, identify the cause of the problem (e.g., bad media, interference, network hardware).


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