Network Plus Certification Study Guide - Bucaro TecHelp

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Oct 23, 2013 (4 years and 2 months ago)

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Contents




Warranty, Disclaimer and Copyright Policy





Introduction

Computer Networking Basics




Computer Networking Basics





Network Topologies





Ethernet Network





Token Ring Network





How to Study For and Pass the CompTIA Network+ Exam

The OSI Reference Model




The OSI Reference Model





The OSI Physical Layer





The OSI Data Link Layer





The OSI Network Layer





The OSI Transport Layer





The OSI Session Layer





The OSI Presentation Layer





The OSI Application Layer





Network Switches





Network Gateways

Networking Topologies and Media




The IEEE 802.3 Ethernet Standards





Fiber Distributed Data Interface





System Area Network Interface Cards





Hubs, Switches and Routers - What's the Difference?

Wireless Networks




Wireless Networks





Overview of IEEE 802.11 Wireless Lan Technology





Understanding Wireless LAN Networking





Bluetooth Basics

Protocol Suites




Protocol Suites





The TCP/IP Protocol Suite

Network Operating Systems




Network Operating Systems

Network Cabling and Components




Network Cabling and Components

TCP/IP




Basic TCP/IP Networking





IP Addressing





IP Addressing and Subnetting





TCP/IP Utilities





Major Protocols in the TCP/IP Suite





Dynamic Host Configuration Protocol (DHCP) Explained





Ports and Sockets

Networking Practices




Network Installation





Network Maintenance





Network Change Control System





Remote Connectivity





Troubleshooting the Network





Creating a Backup Plan





Network Security





How a Firewall Provides Network Security





Implementing a Secure Password Policy





Data Encryption





Wireless Network Security





How to Secure Your Wireless Network





Network Cabling Design

Network Plus Certification Practice Tests




About the Tests





30 TCP/IP Protocol Questions





30 Media and Topologies Questions





40 General Questions





40 Protocols and Standards Questions





30 General Questions





30 Implementation Questions





40 Media and Topologies Questions

Resources




CompTIA Network+ Video Mentor





Network Administrator Street Smarts: A Real World Guide to


CompTIA Network+ Skills

Warranty, Disclaimer and Copyright Policy
This material is provided on an "as-is" basis, and Bucaro TecHelp

makes no warranty or representation, express or implied, with

respect to its quality performance or fitness for a particular purpose.

In no event shall Bucaro TecHelp be liable for direct, indirect, special,

incidental, or consequential damages arising out of the use of this

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No patent liability is assumed with respect to the use of the

information contained herein. Although every precaution has been

taken in the preparation of this manual, Bucaro TecHelp assumes no

responsibility for errors or omissions. Neither is any liability assumed

for damages resulting from the use of the information contained

herein. This information is provided with the understanding that

Bucaro TecHelp is not engaged in rendering medical, legal,

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professional person should be sought.
By using this material, the user assumes complete responsibility for

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materials requires agreement to the terms of this warranty and

disclaimer. If you do not agree to the terms of this warranty, do not

use this material.
Copyright(C)2002-2010 Bucaro TecHelp. Permission is granted for

this program to forward, reprint, distribute, offer as free bonus or

part of a product for sale as long as no changes are made to copies

that are distributed.
Contents
Introduction
It is very difficult for a recruiter or employer to evaluate whether an

individual is competent computer technology professional because the

technology is very complicated. For this reason the Computing

Technology Industry Association (CompTIA) has defined specific skills

and knowledge that a computer technology professional must have.

This is a great advantage to employers because, if an individual

meets the CompTIA standards, they can be confident that the

individual is a competent computer technology professional.
CompTIA does not do any testing itself, it only specifies the skills and

knowledge that a computer technology professional must have to

competently perform the job. The testing is administered by

independent testing organizations such as Sylvan Prometric. When an

individual passes the required examination, CompTIA awards them

certification. CompTIA does not provide any training materials to

prepare for the examinations. Training and and exam preparation is

provided by independent training organizations.
Holding CompTIA certification is a great advantage to a computer

technology professional because it provides proof to employers that

they competence required to perform the job. Certification can help

you acquire employment in the computer technology profession. In

fact many employers require CompTIA certification.
If you are already working in the computer technology field,

certification can help you advance and earn a higher salary. Being

CompTIA certified can give you the self confidence and recognition

you need to compete in today’s demanding job market.
There are several different areas of certification. A+ Computer

Technician was the first certification developed by CompTIA.

Network+ defines specific skills and knowledge that a computer

networking technician must have. It verifies that you have the

knowledge to competently perform the computer networking

technician job.
This ebook provides some training to prepare you for the Network+

certification exam. It is nowhere near complete and there is no

guarantee that reading this ebook will be sufficient for you pass the

exam. You will need to combine the study of this ebook with the

study of other Network+ certification exam preparation materials.

But, after all, this ebook is free and it can be part of your collection of

study materials.
Contents
Computer Networking Basics
By Stephen Bucaro
The Function of a Network
A basic network consists of two or more computers connected to each

other by cable. Computers that are connected to the network can

send messages or email back and forth, and can share data,

applications, and peripherals. A peripheral is a resource such as

printer, modem, disk drive, or other hardware device. Before

networks people shared data files on floppy disks and each computer

needed its own printer.
LANs WANs and MANs
A network that connects together computers in a small area such as a

single building or a floor within a building is called a local area

network (LAN). A network that connects together computers over a

large geographic area, such as different cities is called a wide area

network (WAN).
Peer-to-Peer Network
There are two types of networks, peer-to-peer and server based. A

peer-to-peer network is also referred to as a workgroup. In a

workgroup each user administers their own computer. Security is

implemented by setting the sharing or by setting a password on a

resource. There are typically fewer than ten computers in a peer-to-
peer network. Although it may be less expensive to implement and

administer than a server based network, the server based network

has better security.
Client / Server Network
A server is a computer that is dedicated to performing one or more

specialized functions in the network. File and print servers manage

users access to files and printers. Application servers manage users

access to applications. A server-based network allows central

administration of network resources and security.
Contents
Network Topologies
By Stephen Bucaro
The physical arrangement of the cables, computers and components

is referred to as the networks topology. There are five basic

topologies, bus, star, ring, mesh, and wireless.
Bus Topology
A bus topology consists of a cable that connects all the computers in

the network in a single line. Computers communicate by attaching

the address of the computer meant to receive it to the data and

putting it on the cable. The data, an electronic signal, travels to the

ends of the cable. A component called a terminator is connected to

each end of the cable to absorb the signal and prevent it from

bouncing back.
If the cable is disconnected or physically broken, this would result in

cable ends that do not have a terminator. Signals would bounce,

causing the network communications to fail.
Ring Topology
In a ring topology, all the computers in the network are connected in

a closed loop. The data signal travels around the loop in one

direction, passing through each computer. Whereas bus topology is

passive, in a ring topology each computer boosts the signal before

sending it on to the next computer. Because the signal must pass

through each computer, the failure of one computer can cause the

network to fail.
Star Topology
In a star topology, all the computers in the network are connected by

cable to a central hub. This configuration results in better fault

tolerance because a problem with one cable will not affect the rest of

the network. However, if the central hub fails, it brings down the

entire network. Star topology may require more cable than bus or

ring topology.
Mesh Topology
In a mesh topology, each computer in the network is directly

connected to every other computer in the network. Mesh topology

has very high fault tolerance because if one cable breaks, several

alternate routes are available. Mesh topology is very complex and

requires a large amount of cable. It is not cost effective to implement

except for the most mission critical systems.
Wireless Topology
A wireless network dosn't use cables. Instead a wireless network uses

infrared light beams or radio waves to communicate. The wireless

network consists of transceivers called access points. The computers

in a wireless network each have their own transceivers to

communicate with an access point. In an infrared light network, the

client and the access point must be in line-of-sight.
Logical vs. Physical Topology
The
logical topology
is the way the data is transferred between

devices on a network, as apposed to the
physical topology
which is

the actual physical layout of the network cabling. The logical topology

of a network is not necessarily the same as its physical topology. For

example, Ethernet networks use the
bus
logical topology, but

commonly use the
star
logical topology.
Understanding the difference between the logical and physical

topology of a network is important in troubleshooting. For example, in

an Ethernet network, although each network device physically

connects to a hub, its logical topology means that a single

malfunctioning device can transmit bad packets to all other devices

on the same subnet.
Contents
Ethernet Network
By Stephen Bucaro
In 1973 Xerox invented Ethernet to solve the problem of transferring

data between computers. Digital Equipment and Intel collaborated

with Xerox in 1973 to publish the DIX networking standard. In the

early 1980s Xerox turned over control of the Standard to the Institute

of Electrical and Electronics Engineers (IEEE). The IEEE sets up

committees to define industry standards. The IEEE 802 committee

sets the standards for networking. The IEEE subcommittee 802.3 sets

the standard for Ethernet.
An Ethernet packet contains four main parts: The data, the MAC

address of the packets source, the MAC address of the packets

destination and an error checking code. When creating a packet, the

sending computer performs a mathematical operation on the data

and attaches the result, called the cyclic redundancy check (CRC), to

the packet. The receiving computer performs the same operation on

the data and compares its result with the CRC. If the two results do

not match, an error has occurred in transmission of the data. The

receiving computer will send a request to the sending computer to

retransmit the packet.
CSMA/CD
Ethernet networks use the access method known as Carrier Sense

Multiple Access with Collision Detection (CSMA/CD).
Multiple access

means that several computers share the same cable. But only one

computer can place a data packet on the cable at a given instant.

Carrier sense
means that before a computer places a data packet on

the cable, it checks or
senses
the cable to make sure no other

computer is using the cable. If it senses traffic on the cable, it will

wait until the cable is free. When the computer senses that there is

no traffic on the cable, it will send out its data packet.
If two computers sense that there is not traffic on the cable and start

transmitting at exactly the same instant, the data packets will collide.

Collision detection
means that both computers can detect if a collision

has occurred. If they detect a collision, both computers stop

transmitting. Each computer then generates a random number and

waits for a period of time equal to that number before attempting to

transmit again.
On very long cables, beyond 2,500 meters, computers on opposite

ends of the cable cannot detect the start of a transmission on the

opposite end of the cable quick enough to avoid an undetected

collision. An undetected collision will result in corruption of the data

packet.
You might think a system designed with the possibility of having data

packet collisions is somewhat crude. But data collisions occur rarely

during normal operation of an Ethernet network and they have little

affect on the efficiency of the network. As network traffic increases,

collisions occur more frequently and have the effect of limiting the

bandwidth (maximum operating speed) of the network.
A modification of the CSMA/CD access method features collision

avoidance. In the Carrier Sense Multiple Access with Collision

Avoidance (CSMA/CA) access method, a computer broadcasts a

message on the network to signal its intent to transmit before it

places a data packet on the cable. The other computers on the

network then refrain from transmitting data, thus avoiding collisions.

However, the broadcasting of messages increases the amount of

traffic on the cable, resulting in little or no performance gain over

CSMA/CD.
Contents
Token Ring Network
By Stephen Bucaro
Token Ring technology was invented by IBM in 1984 and defined in

standard IEEE 802.5 by the Institute of Electrical and Electronics

Engineers. The token ring network has a logical ring topology, and

may be setup with a physical ring topology, but is usually

implemented in a physical star topology.
The central device of a token ring, called a
Media Access Unit
(MAU)

or
Multistation Access Unit
(MSAU), can be thought of as a "Ring in a

Box". It allows multiple network stations in a logical ring to connect

as a physical star. The loop that used to make up the ring is

integrated into a chip.
In a physical Token ring topology, when a cable is open or a station is

not operating, the entire network goes down. However with a MAU,

the broken circuit is shorted out, closing the loop so the network can

continue to operate and the nonoperating stations may be unplugged

without crashing the entire network.
Token ring protocol operates at the data link layer of the OSI model.

In a token ring network, the first computer to come online creates a

three-byte data frame called a
token
. The token is sent on the cable

to the next node in the ring. The token continues around the ring

until it arrives at a node that wants to transmit data. The node that

wants to transmit data takes control of the token.
A node can only transmit data on the network cable when it takes

control of the token. Since only one token exists, only one node can

transmit at a time. This prevents the collisions that might occur with

the Ethernet CSMA/CD access method.
After a node takes control of the token, it transmits a data packet. A

Token Ring packet contains four main parts: The data, the MAC

address of the packet’s source, the MAC address of the packet’s

destination and a Frame Check Sequence (FCS) error checking code.
The data packet continues around the ring until it reaches the node

with the destination address. The receiving node accepts the data and

marks the packet that the data was received. The data packet then

continues around the ring until it reaches the source node again. The

source node removes the packet from the cable and releases the

token so that another node may transmit.
Initially token ring ran at 4 Mbit/s, In 1989 IBM introduced the 16

Mbit/s token ring. Other companies introduced proprietary 10 Mbit/s

and 12 Mbit/s versions of token ring. Speeds of 4 Mbit/s, 16 Mbit/s,

100 Mbit/s and 1 Gbit/s have been standardized by IEEE 802.5.
Contents
Network Plus Certification Practice Tests
Note: These tests work only with Internet Explorer. The tests use

XML and unfortunately Internet Explorer and Firefox are not

compatible with how they deal with XML. I'm in the process of making

the tests cross-browser, but at the current time, the tests work only

with Internet Explorer.
These self tests will help you prepare for the CompTIA Network+

Certification Exam. This application uses Java Script and frames, so

you must have these features enabled in your browser. To start a

text, click on the [Start Test] link.
Questions that you answer by setting a radio button will accept only a

single answer. Questions that you answer by checking a checkbox

require you select more than one answer.
After answering a question, click on the [Next] button, except for the

last question, which does not have a [Next] button. You can go back

to review previous questions by clicking on the [Back] button. You

may change your answer to a previous question.
Each question is accompanied by a scrolling "cheat" box. The cheat

box provides some information that will help you answer the

question. The cheat information is not visible until you scroll the

cheat box.
At any time during the test, you can click on the [Score Test] link to

receive a test score based upon the number of questions completed.

Your score will display a list of the questions that you answered

incorrectly, along with the correct answers and the percentage of

questions answered correctly.
Achieving a high score on any single practice test does NOT

guarantee that you will pass the CompTIA Certification Exam. You

need to achieve a high score on a variety of preparation self tests

from this Web site and other sources before attempting the actual

CompTIA Certification exam.
If you find a problem with any question on the self test, or if a test

application itself doesn't work properly, I would appreciate a quick

note through the contact form on this Web site.
Contents
How to Study For and Pass the CompTIA Network+ Exam
By Stephen Bucaro
CompTIA certification is a great advantage to a computer technology

professional because it provides proof to employers that they have

the competence required to perform the job. Certification can help

you acquire employment in the computer technology profession. In

fact, many employers require CompTIA certification.
If you are already working in the computer technology field,

certification can help you advance and earn a higher salary. Being

CompTIA certified can give you the self confidence and recognition

you need to compete in today’s demanding job market.
In this article, you'll learn how to study for and pass the CompTIA

Network+ exam. You will not be learning any tricks here. Passing the

exam is hard of work, but nothing worth while is ever easy. But, is it

worth while? The median salary for a Network Administrator with 2-4

years of experience is $52,493.
Here's how to study
Get five or six good quality comprehensive self tests and take them.

If you miss a question on a self test, re-study that subject and take

the test again. Keep re-taking the self tests until you regularly pass

them with a score of 90 percent or higher.
Why five or six self tests? Because if you use only one text, you'll

have the answers to the questions on that specific test memorized.

When you take the actual exam, you'll be presented with an entirely

new set of questions. Even if you purchase an expensive application

that generates tests by randomly selecting questions from a data

base of thousands of questions, those questions where created by the

one individual or company. Each test creator has their own point of

view that may not be in agreement with the point of view of

CompTIA's test writers.
Why pass with a score of 90 percent? Because the minimum passing

score for the CompTIA Network+ exam is 82 percent. You need a

safe margin between your self test scores and 82 percent. If you

frequently pass your self tests with a score of 82 percent, you'll need

luck to pass the actual exam. If you're not lucky, you'll pay $185.00

to take the exam twice (or more).
Shouldn't I wait until I always pass the self tests with a score of 100

percent? Even the best self tests (and the CompTIA exams) contain

questions that use improper grammar, have incorrect answers, or are

just plain stupid. Sometimes you can't get a 100 percent unless you

deliberately answer the question incorrectly - and that's not good

practice.
Setup a Computer Lab
I recommend that you set up a lab with three computers, one to act

as a server and two to act as work stations. Then design a fake

company and set up home directories and user accounts for the

employees of the company. It's very difficult to pass the certification

test without some hands-on experience. Straight memorization won't

prepare you for the scenario type questions on the exam.
In my opinion, you can't get the required hands-on experience with

just one computer. To "network", you need several computers to

network. If setting up a lab is a matter of cost, you can get used

computers for only a couple hundred bucks - not a bad investment for

a $52,493 a year job. If it takes you several tries to pass the test

(which is common), then you end up burning the same amount of

cash as you would if you set up a lab.
If workarea to setup a computer lab is the problem, you can buy used

notebook computers, as long as they have an Ethernet port.


Getting real hands-on experience is critical for your performance

after you get a job. It can cost a large corporation hundreds of

thousands of dollars each minute that a network is down. You don't

want to be sitting there in front of experienced network

administrators with your hands shaking because you're too scared to

do anything. Maybe they'll let you be their coffee goafer for a week

until you get fired. Setup a computer lab.
How Long Will it Take?
How long it takes to study for the exam depends upon how smart you

are and how much experience you have. Some say if you have no

experience it will take 30 hours of study to pass the test. Don't make

me laugh! If you have no experience, you better double that. And if

you can't study for at least five hours each week, you are probably

wasting your time because you'll forget the material faster than you

learn it. I would use a rough estimate of six weeks.


The actual time required to study for the exam is determined by

when you regularly pass the self tests with a score of 90 percent or

higher.


The most important element for success in pursuit of CompTIA

Network+ certification is to schedule study time and during that

scheduled study time make study your first priority.
Which Materials are Best for Preparing for the Exam?
Each author/publisher has their own idea about what material to

emphazise and what approach to take, so you should purchase

several different CompTIA Network+ certification study guides.

Another advantage to using several different study materials is that

they reinforce each other. You should give preference to study guides

that include a CD ROM containing self tests.
This book focuses exactly on what you need to know to pass the

exam, plus test-taking strategies, time-saving study tips, and a

special Cram Sheet that includes tips, acronyms, and memory

joggers not available anywhere else. The accompanying CD features

PrepLogic™ Practice Tests, Preview Edition. This product includes one

complete PrepLogic Practice Test with approximately the same

number of questions found on the actual vendor exam. Each question

contains full, detailed explanations of the correct answers.
A reader in Massachusetts says, "I just used this book and a few

online tests and got an 833/900 on the exam. The book pretty much

covers everything, just read it through a few times and take the

practice tests and you should pass easily."
Another book by Michael Meyers, but this one is more concise, well

formatted, and a size that makes it a more portable study tool with

an intensive focus only on what you need to know to pass the exam

plus practice exam software on CD.
Reader John Matlock from Winnemucca Nevada says, "Although this

book is oriented towards the passing of the CompTIA Network+

certification test, it is also an excellent introduction to networking. It

can be used by anyone all of a sudden in over his head in getting a

network set up and running. The text is written very straight and to

the point. A lot of books of this type spend a lot of time rambling on

about theory. This one doesn't."
Passing the CompTIA Network+ certification exam is hard of work,

but for a career with a salary of $52,493, it's worth it. The way to

pass the exam is to use the materials described above to study and

keep taking the self tests until you regularly pass them with a score

of 90 percent or higher. Then you can take the certification exam

confidently and pass on the first try.
Contents
The OSI Reference Model
By Stephen Bucaro
In 1984 the International Standards Organization (ISO) released a

network reference called the Open System Interconnect (OSI) model.

This model defines a network operating system as having seven

layers, each layer performing a specific task.
No real world network operating systems conform exactly to the OSI

model, but it is useful as a reference when describing existing

systems. It is difficult to study network devices such as routers,

switches, and gateways without using the model. It is also difficult to

describe and compare networking protocols such as TCP/IP and

IPX/SPX without using the OSI model as a reference.
Layer 7
Application
Layer 6
Presentation
Layer 5
Session
Layer 4
Transport
Layer 3
Network
Layer 2
Data Link
Layer 1
Physical
Frequently you will see a table of the layers inverted from that shown

above, with Layer 1, the Physical layer on top. This causes confusion

in the learning process when data is described as
moving up the OSI

model
or when a
higher layer
is referred to. Be alert to this

possibility.
OSI Layers
Layer
Description
Application
This layer provides the interface to the

network for the Network Operating System

(NOS). It provides network services and

applications such as HTTP, FTP, TELNET

and SMP.
Presentatio
n
This layer provides character set conversion

and formats the data, It performs encryption

and decryption, compression and

decompression.
Session
This layer authenticates security and

establishes a connection ID. It establishes,

synchronizes, maintains and ends sessions.
Transport
This layer repackages messages that are too

long into smaller segments. It adds segment

sequencing numbers, provides message

multiplexing and manages flow control. At

the receiving end it provides error detection

and recovery, and reassembles the segments

in the proper order.
Network
This layer breaks data into smaller units and

assigns logical addresses. It determines the

route from source to destination. On the

receiving end it translates logical addresses

into physical addresses and reassembles the

units. This layer manages network traffic

and routing.
Data Link
This layer organizes data into frames and

assigns the physical address. It provides

flow control and packages bits from the

physical layer into frames and provides

error checking and correction.
Physical
This layer describes the physical

components of the network, which includes

network interface cards, cables and

connectors. It converts digital bits into

electronic signals for sending on the

network, and converts received signals into

digital bits.
Don’t worry if you don’t understand the descriptions of each layer at

this time. Further explanations will follow. If you will need to be able

to recall the order of the layers. You can do that by memorizing the

phrase: All People Seem To Need Data Processing.
Physical Layer
The Physical layer (OSI layer 1) deals with the mechanical and

electrical specifications of the network hardware. Layer 1

specifications define connectors, pin-outs, signal voltages, and related

software.
The most common Physical layer component is the Network Interface

Card (NIC). To install a NIC you need to assign computer resources

such as an IRQ and I/O address. If the operating system and NIC are

Plug-and-Play (PnP), these resources will be assigned automatically.
A repeater is a Physical layer device that amplifies, reconstructs and

retransmits the signal, allowing you to extend the length of a network

cable.
Hub and MAU
Another common Physical layer device is the Ethernet hub. A hub is

used as a central point to connect network devices. When a signal

arrives at one of the hub’s ports, it is sent to all the other ports on

the hub. A hub does not segment a network as a switch does. Most

hubs provide a cascade port that allows you to stack hubs to provide

more ports.
A token ring network uses a Multi-station Access Unit (MAU) rather

than a hub. If the MAU detects an error on a port, the MAU can

automatically bypass that port to maintain the operation of the ring.

Most MAU’s provide a ring-in port and a ring-out port that permit you

to stack MAU’s to provide more ports.
Data Link Layer
The Data Link layer (OSI layer 2) contains two sub-layers; the Logical

Link Control (LLC), and the Media Access Control (MAC). IEEE

specification 802.2 defines the LLC, while the IEEE specifications

802.3 and 802.5 define the MAC for Ethernet and Token Ring.
All hosts on a network, including network devices such as printers

and routers, must have a unique identifier called the Media Access

Control address. The Data Link layer uses MAC addresses is to pass

data frames from the Physical layer to the Network layer and vice

versa. The use of MAC addresses permits the direction of data within

the same network, but not across routers.
The Bridge and Switch
The major network device that operates at the Data Link layer is the

bridge and switch. The bridge stores a list of MAC addresses that are

connected to each of its ports. It reads the destination MAC address

in each packet it receives. Because the bridge does not modify the

packet in any way, the process is called
transparent bridging
.
If the destination is on the same network segment the bridge

discards the packet. If the destination is on a different segment, the

bridge forwards the packet to the proper segment. If the bridge’s

MAC address table does not list the destination, the packet is

forwarded to all segments except the segment of origin and waits for

a device to respond. If a device responds, the bridge can update its

MAC address table to include that MAC address.
A switch is similar to a bridge in the way it forwards packets through

a network, except the switch can forward packets between ports

simultaneously. A switch can segment a network into as many parts

as the number of ports the switch has. In an entirely switched

network, each device connects to a switch rather than a hub. This

allows for the speed of the network to be the combined speed of all

the ports.
Network Layer
The Network layer (OSI layer 3) uses routable protocols to deliver

data packets to networks connected through routers. To route data

packets, the Network layer uses logical addressing. Routing is the

process of moving data packets from one network or network

segment to another.
Each LAN or network segment has a unique logical address. The

Network layer protocol adds a source node address and a destination

node address to each data packet. A packet that has a destination not

on the local subnet is sent to a node called a
default gateway
that can

communicate outside the local subnet.
Inter-network Packet Exchange (IPX) is a NetWare protocol that

performs the Network layer functions for a NetWare IPX/SPX

network. The IPX protocol uses a 32-bit network address and a 48-bit

node address. IPX/SPX was a popular protocol suite for several years,

but it has been replaced by the TCP/IP suite on most networks.
Transport Layer
The Transport layer (OSI layer 4) uses connection-oriented protocols

to provide a reliable end-to-end connection between the source

computer and the destination computer. Transmission Control

Protocol (TCP) is a transport layer protocol that provides flow control,

multiplexing, error detection and recovery.
At the transmitting end, the message is broken into smaller segments

and each segment is given a sequence number. At the receiving end

the segments are checked for errors. If the segments are received

error free, they are reassembled in the proper sequence and an

acknowledgement is sent to the transmitting computer. If the

transmitting computer does not receive an acknowledgement, it

resends the segments.
Session Layer
This layer authenticates security and establishes a connection ID. It

establishes, synchronizes, maintains and ends sessions. Remote

Procedure Call (RPC) is a protocol that runs at the Session layer. RPC

allows communication between processes on different systems.
Presentation Layer
At this layer applications communicate on a format for exchanging

data. The Session layer provides character set conversion and

formats the data. It performs encryption and decryption, compression

and decompression.
Application Layer
This layer provides the interface between applications and the

Network Operating System (NOS). The Application layer provides

network services and applications such as HTTP, FTP, TELNET and

SMP.
Although no real world network operating systems conform exactly to

the OSI model, It would be difficult to describe the operation of

network devices and protocols without using the model as a

reference.
Contents
The OSI Physical Layer
By Stephen Bucaro
The Physical layer (OSI layer 1) deals with the mechanical and

electrical specifications of the network hardware. Layer 1

specifications define connectors, pin-outs, signal voltages, and related

software.
The most common Physical layer component is the Network Interface

Card (NIC). To install a NIC you need to assign computer resources

such as an IRQ and I/O address. If the operating system and NIC are

Plug-and-Play (PnP), these resources will be assigned automatically.
NIC MACs
Each computer connects to the network utilizing a network interface

card (NIC) that may be installed in an expansion slot inside the

computer, or the NIC electronics may be integrated into the

computers motherboard. Each NIC has a unique identifying number

called a media access control (MAC) address. No two NICs ever have

the same MAC address. The MAC address is 48 bits, allowing more

than 281 trillion possible unique addresses.
Computer networks break the data transmitted over the network into

small pieces called packets. Dividing a large document into small

packets for transmission allows computers to share the network

cable, rather than having one large transmission prevent other

computers from using it. If an error occurs during transmission, only

the damages packet needs to be retransmitted, rather than the entire

large document.
IEEE 802.3 - Ethernet
In 1973 Xerox invented Ethernet to solve the problem of transferring

data between computers. Digital Equipment and Intel collaborated

with Xerox in 1973 to publish the DIX networking standard. In the

early 1980s Xerox turned over control of the Standard to the Institute

of Electrical and Electronics Engineers (IEEE). The IEEE sets up

committees to define industry standards. The IEEE 802 committee

sets the standards for networking. The IEEE subcommittee 802.3 sets

the standard for Ethernet.
An Ethernet packet contains four main parts: The data, the MAC

address of the packets source, the MAC address of the packets

destination and an error checking code. When creating a packet, the

sending computer performs a mathematical operation on the data

and attaches the result, called the cyclic redundancy check (CRC), to

the packet. The receiving computer performs the same operation on

the data and compares its result with the CRC. If the two results do

not match, an error has occurred in transmission of the data. The

receiving computer will send a request to the sending computer to

retransmit the packet.
CSMA/CD
Ethernet networks use the access method known as Carrier Sense

Multiple Access with Collision Detection (CSMA/CD).
Multiple access

means that several computers share the same cable. But only one

computer can place a data packet on the cable at a given instant.

Carrier sense
means that before a computer places a data packet on

the cable, it checks or
senses
the cable to make sure no other

computer is using the cable. If it senses traffic on the cable, it will

wait until the cable is free. When the computer senses that there is

no traffic on the cable, it will send out its data packet.
If two computers sense that there is not traffic on the cable and start

transmitting at exactly the same instant, the data packets will collide.

Collision detection
means that both computers can detect if a collision

has occurred. If they detect a collision, both computers stop

transmitting. Each computer then generates a random number and

waits for a period of time equal to that number before attempting to

transmit again.
On very long cables, beyond 2,500 meters, computers on opposite

ends of the cable cannot detect the start of a transmission on the

opposite end of the cable quick enough to avoid an undetected

collision. An undetected collision will result in corruption of the data

packet.
You might think a system designed with the possibility of having data

packet collisions is somewhat crude. But data collisions occur rarely

during normal operation of an Ethernet network and they have little

affect on the efficiency of the network. As network traffic increases,

collisions occur more frequently and have the effect of limiting the

bandwidth (maximum operating speed) of the network.
A modification of the CSMA/CD access method features collision

avoidance. In the Carrier Sense Multiple Access with Collision

Avoidance (CSMA/CA) access method, a computer broadcasts a

message on the network to signal its intent to transmit before it

places a data packet on the cable. The other computers on the

network then refrain from transmitting data, thus avoiding collisions.

However, the broadcasting of messages increases the amount of

traffic on the cable, resulting in little or no performance gain over

CSMA/CD.
Token Ring Network
In 1984 IBM invented Token Ring. The token ring network may be

setup with a physical ring topology, but is usually implemented in a

physical star topology.
The central device of the token ring is called a Multistation Access

Unit (MSAU or MAU).
In a token ring network, the first computer to come online creates a

data frame called a
token
. The token is sent on the cable to the next

node in the ring. The token continues around the ring until it arrives

at a node that wants to transmit data. The node that wants to

transmit data takes control of the token.
A node can only transmit data on the network cable when it takes

control of the token. Since only one token exists, only one node can

transmit at a time. This prevents the collisions that might occur with

the Ethernet CSMA/CD access method.
After a node takes control of the token, it transmits a data packet. A

Token Ring packet contains four main parts: The data, the MAC

address of the packet’s source, the MAC address of the packet’s

destination and a Frame Check Sequence (FCS) error checking code.
The data packet continues around the ring until it reaches the node

with the destination address. The receiving node accepts the data and

marks the packet that the data was received. The data packet then

continues around the ring until it reaches the source node again. The

source node removes the packet from the cable and releases the

token so that another node may transmit.
Hub and MAU
Another common Physical layer device is the Ethernet hub. A hub is

used as a central point to connect network devices. When a signal

arrives at one of the hub’s ports, it is sent to all the other ports on

the hub. A hub does not segment a network as a switch does. Most

hubs provide a cascade port that allows you to stack hubs to provide

more ports.
A token ring network uses a Multi-station Access Unit (MAU) rather

than a hub. If the MAU detects an error on a port, the MAU can

automatically bypass that port to maintain the operation of the ring.

Most MAU’s provide a ring-in port and a ring-out port that permit you

to stack MAU’s to provide more ports.
Contents
The OSI Data Link Layer
By Stephen Bucaro
The Data Link layer (OSI layer 2) contains two sub-layers; the Logical

Link Control (LLC), and the Media Access Control (MAC). IEEE

specification 802.2 defines the LLC, while the IEEE specifications

802.3 and 802.5 define the MAC for Ethernet and Token Ring.
All hosts on a network, including network devices such as printers

and routers, must have a unique identifier called the
Media Access

Control
address. The Data Link layer uses MAC addresses is to pass

data frames from the Physical layer to the Network layer and vice

versa. The use of MAC addresses permits the direction of data within

the same network, but not across routers.
The Bridge and Switch
The major network device that operates at the Data Link layer is the

bridge and switch. The bridge stores a list of MAC addresses that are

connected to each of its ports. It reads the destination MAC address

in each packet it receives. Because the bridge does not modify the

packet in any way, the process is called
transparent bridging
.
If the destination is on the same network segment the bridge

discards the packet. If the destination is on a different segment, the

bridge forwards the packet to the proper segment. If the bridge’s

MAC address table does not list the destination, the packet is

forwarded to all segments except the segment of origin and waits for

a device to respond. If a device responds, the bridge can update its

MAC address table to include that MAC address.
A switch is similar to a bridge in the way it forwards packets through

a network, except the switch can forward packets between ports

simultaneously. A switch can segment a network into as many parts

as the number of ports the switch has. In an entirely switched

network, each device connects to a switch rather than a hub. This

allows for the speed of the network to be the combined speed of all

the ports.
The Bridge
A bridge operates at the Data Link layer of the OSI model; therefore,

it can read the MAC addresses in the data packets. A bridge has

internal RAM. When a bridge first starts up, it behaves like a

repeater. But as the bridge receives packets from each segment of

the network, it builds a table of the source MAC addresses on each

segment.
When the bridge receives a data packet, it looks up the MAC address

in the list stored in its RAM to determine on which network segment

the packet's destination resides. If the destination address is not on

the same segment as the source, the bridge will forward the packet

to the other segment. If the destination is on the same segment as

the source it will filter, or stop, the packet from passing through to

the other segment.
The process of filtering packets results in each network segment

carrying fewer packets. Less traffic on each segment means fewer

collisions. The network is divided into two separate "collision

domains", each with fewer collisions than the original single collision

domain. Both segments and the entire network operate with greater

efficiency.
Network data packets can be either "unicast" or "broadcast". Unicast

means the packet's destination is a single device. At times it is

desired to send a broadcast message to all nodes on the network.

This might be necessary, for example, to trouble shoot the network.

Bridges always forward all broadcast packets.
When a bridge forwards a packet, it copies it exactly, leaving the

original source MAC address. Bridges are said to be "transparent" or

"invisible". Because a bridge does not require any configuration, they

are the easiest way to break a high traffic network into two segments

in order to increase its efficiency.
Bridges cannot connect two segments with different access methods,

such as Ethernet to Token Ring, nor can they connect two different

media types such as 10Base2 and 10BaseT. This can be achieved

with special transitional bridges, but these are rarely used because

another method, such as the use of a gateway device, is better. A

bridge may be a stand-alone piece of equipment, or it can be

implemented as software installed on a server.
Contents
The OSI Network Layer
By Stephen Bucaro
If you have a very large network, you may divide the network into

several segments and assign a network address to each segment.

The Network layer, layer three of the OSI model, adds a source node

address and a destination node address to each data packet. The

Network layer uses logical addressing. Routable protocols at the

Network layer deliver data packets to networks connected through

routers
.
The Network layer protocol adds a source node address and a

destination node address to each data packet. Each LAN or network

segment has a unique logical address.
Internet Control Message Protocol (ICMP)
ICMP is a Network layer protocol that reports on the success or failure

of data delivery. It detects error conditions such as "Network

unreachable" or "Access denied". It can indicate when part of a

network is congested, when data fails to reach its destination, or

when data has been discarded because the allotted time for its

delivery (TTL) has expired.
ICMP anounces transmisssion failures to the sender, but ICMP cannot

correct any of the errors it detects. The ICMP announcements provide

information to upper-layer protocols so that they can route packets

around problem areas.
Router
Routing is the process of moving data packets from one network or

network segment to another. A packet that has a destination not on

the local subnet is sent to a node called a
default gateway
that can

communicate outside the local subnet.
A router uses a
routing table
to determine which router is conected to

the network that has the computer with the destination address.

Routing protocols such as OSPF (Open Shortest Path First) Network

layer are used to update the routing table.
Routing uses the Network layer of the OSI model to direct data

packets to the proper network or subnetwork.
Contents
The OSI Transport Layer
Stephen Bucaro
The Transport layer (OSI layer 4) uses connection-oriented protocols

to provide a reliable end-to-end connection between the source

computer and the destination computer. Transmission Control

Protocol (TCP) is a transport layer protocol that provides flow control,

multiplexing, error detection and recovery.
Layer 7
Application
Layer 6
Presentation
Layer 5
Session
Layer 4
Transport
Layer 3
Network
Layer 2
Data Link
Layer 1
Physical
At the transmitting end, the message is broken into smaller segments

and each segment is given a sequence number. At the receiving end

the segments are checked for errors. If the segments are received

error free, they are reassembled in the proper sequence and an

acknowledgement is sent to the transmitting computer. If the

transmitting computer does not receive an acknowledgement, it

resends the segments.
Other Transport Protocols
Sequenced packet Exchange (SPX) is a NetWare protocol that

performs the Transport layer functions for a NetWare IPX/SPX

network. IPX/SPX was a popular protocol suite for several years, but

it has been replaced by the TCP/IP suite on most networks.
User Datagram Protocol (UDP) is a connectionless Transport layer

protocol used to send time sensitive data such as real-time audio and

video. No error checking is performed and no packet receipt

acknowledgement is returned to the transmitting computer. Since the

data is being processed in real-time, it makes no sense to retransmit

a packet that has already been presented.
The Transport layer does not establish nor terminate a network

connection. It is the Session layer (OSI layer 5) that establishes,

maintains, and terminates the connection. The Transport layer is not

involved in routing the packets from the source to the destination.

The Network layer (OSI layer 3) assigns logical addresses to the

packets and routes them through the network. Once the Session

layer and the Network layer establish a virtual circuit, the Transport

layer provides reliable delivery of the data.
Contents
The OSI Session Layer
By Stephen Bucaro
The Session layer, layer seven of the OSI model, establishes,

synchronizes, maintains and terminates sessions between computers

on a network. It establishes a connection ID and authenticates

security.
When you think of the Session layer, keep in mind that the OSI is

only a model. Actual network protocol suites, such as TCP/IP handle

the conection establishment, maintainance, and termination with

protocols at the Transport layer.
Contents
The OSI Presentation Layer
By Stephen Bucaro
At the presentaion layer, layer six of the OSI model,source and

destination applications communicate on a format for exchanging

data. The sending computer may convert text to a generic format

( ASCII) for transmission over a network. The receiveing computer

converts the ASCII to the format required by the destination

application.
Data Transformation Services Provided by the Presentation Layer


Text format conversions


Binary and graphics format conversions


Compression and expansion


Encryption and decryption
When you think of the Application layer, keep in mind that the OSI is

only a model. Actual network operating systems may handle the data

conversion functions at the application and session layers.
Contents
The OSI Application Layer
By Stephen Bucaro
The Application layer, layer seven of the OSI model, provides the

interface between applications and the Network Operating System

(NOS). The Application layer provides network services and

applications such as HTTP (Hypertext Transfer Protocol), FTP (File

Transfer Protocol), TELNET, SNMP (Simple Netwrok Management

Protocol) and SMTP (Simple Mail Transport Protocol).
When you think of the Application layer, don't think in terms of

applications, but rather protocols. For example there are several

different FTP applications that use the FTP
protocol
at the Application

layer.
Contents
The IEEE 802.3 Ethernet Standards
By Stephen Bucaro
The Institute of Electrical and Electronics Engineers (IEEE). The IEEE

sets up committees to define industry standards. The IEEE 802

committee sets the standards for networking. The IEEE subcommittee

802.3 sets the standard for Ethernet.
The IEEE created a system to specify network cabling. For example,

in the designation
10base5
, the
10
specifies the maximum speed in

megabits per second at which the cable can transfer data.
Base

stands for baseband signal type. Baseband means it uses a digital

signal. The
5
specifies that 500 meters the maximum length of a

cable segment.
10Base5 Thicknet
Speed: 10Mbps
Cable: thicknet coaxial
Maximum Length: 500 meters (1,640 feet)
Coaxial Cable (coax) uses a solid wire in its core that is surrounded

by a braided metal shield. Insulating material separates the wire core

and metal shield. The central wire carries the electrical signal of the

network data. The metal shield protects the data from electrical

interference. Early Ethernet networks used thick RG-8 coaxial cable.

This cable is referred to as Thicknet.
Thicknet cable is very rigid, so the network computers and

peripherals do not connect directly to the cable. Each computer or

other device, referred to as a
node
, connects to the coax using a

thinner
drop cable
. The Thicknet
backbone
may run in the ceiling,

with drop cables used to attach the individual computers. Each drop

cable is connected to the Thicknet backbone using a transceiver.
To attach a transceiver to the Thicknet cable requires a technician to

cut a hole through the cable shield and attach a
vampire tap
which

pierces the wire core of the coaxial cable. The transceiver is then

connected to the network interface card (NIC) of the computer using

a cable with a DB-15 connecter called a DIX (Digital Intel Xerox) or

AUI (Attachment Unit Interface).
Transceivers may be placed no closer together than 2.5 meters and

the transceiver drop cable may be no longer than 50 meters. No

more than 100 nodes may be connected to the Thicknet segment.
Because of the high cost and difficulty of installation, Thicknet is

rarely used today. If it is already installed, or if there is high electrical

interference in the environment, it may still be used. Large networks

may use Thicknet as a main backbone cable to connect branch

network segments.
10Base2
Speed: 10Mbps
Cable: thinnet coaxial
Maximum Length: cable 185 meters (607 feet)
Note: Following the IEEE namings scheme, You might think the "2" in

10Base2 means that the maximum length of a cable segment is 200

meters, but the maximum length of 10Base2 is only 185 meters.
In most LAN installations the nodes are much closer together than

500 meters, so the high cost of thicknet was not justified. A thinner

more flexible coaxial cable called "thinnet" could be used when the

cable lengths where 185 meters or less.
The Thinnet network cable does not use a drop cable, but

instead connects directly to a computer's NIC using a BNC

"T" Connector.
The electronic signal travels through the BNC T connectors

to each node on the bus and to the ends of the cable. A BNC

terminator is connected to each end of the cable to absorb

the signal and prevent it from bouncing back.
If a coax cable needs to be extended, two pieces of cable can be

connected together using a barrel connector. But if the entire

length of the cable segment is longer than 185 meters, the signal

will attenuate (weaken) to the point of becoming unreliable.
The signal is also attenuated slightly anytime it encounters a T

connector or barrel connector. For this reason a 10Base2 network

may have a maximum of only 30 nodes on a segment.
Almost all texts state that the acronym BNC stands for British Navel

Connector. This is an error. The central wire of the coaxial cable is

connected by means of a "bayonet" at the center of the connector. The

coaxial cable shield is connected by rotation of a metal nut with a locking

grove. The proper name for the BNC connector is Bayonet Nut Connector.
Because of the high cost, Thinnet coaxial cable is rarely used today.

Almost all networks today use Unshielded Twisted Pair (UTP) cable.
10BaseT
Speed: 10Mbps
Cable: shielded or unshielded twisted-pair
Maximum Length: cable 100 meters (328 feet)
Maximum number of nodes per segment: 1024 Connector: RJ-45
Almost all networks today use Unshielded Twisted Pair (UTP) cable.

Some older networks use Shielded Twisted Pair (STP), which is

similar to UTP but has metal shielding to prevent electrical

interference. But unless it is already installed, or there is high

electrical interference in the environment, UTP is used for network

cabling.
A twisted pair is two insulated copper wires twisted around each

other. A UTP cable usually contains four twisted pair (8 wires).

10BaseT is similar to telephone cable. Both types of cable have

similar connectors, except the UTP networking connector, designated

as RJ-45, is larger and has eight contacts compared to the telephone

cables smaller RJ-11 connector which has four contacts.
EIA/TIA Cable Categories
The Electronics Industries Association/Telecommunication Industries

Association set a standard for UTP cable (EIA/TIA 568A). The

standard, which relates primarily to the maximum speed supported

by a cable, has five categories.
Category
Max Speed Mbps
1
Analog voice only
2
4
3
16
4
20
5
100
Because the cost is only slightly higher, and to allow for future

upgrades, most networks use category 5 cable.
IEEE 802.3u 100BaseTX
Speed: 100Mbps
Cable: shielded or unshielded twisted-pair
Maximum Length: cable 100 meters (328 feet)
Maximum number of nodes per segment: 1024
100BaseTX is referred to as "Fast Ethernet". In order to reliably

achieve the higher speeds, 100BaseTX requires category 5 UTP.
100BaseT4
100BaseT4 was designed to allow Fast Ethernet over lower grade

Category 3 and Category 4 cabling. This is accomplished by using the

second pair of wires for the collision detection function. 100BaseT4 is

normally used only where the lower grade cabling is already in place.
100BaseFX
100BaseFX is Fast Ethernet over fiber-opic. Fiber optic cable has a

glass or plastic core. Pulses of light carry the network data. Because

light is not effected by electrical interference, the maximum length

for a fiber optic cable is 2 kilometers. 100BaseFX is a good cable

choice for environments with high electrical interference. It is also

more difficult to tap into a fiber optic cable, so it provides a more

secure network.
There are two kinds of fiber optic connectors, SC and

ST. The picture to the left shows type SC
IEEE 802.12 100BaseVG-AnyLAN
100BaseVG-AnyLAN is another specification designed to allow Fast

Ethernet over lower grade Category 3 cabling.
IEEE 802.3z 1000BaseX
Known as "gigabit Ethernet", 1000BaseX uses laser-based fiber-optic

to transmit data at 1,000Mbps.
Contents
Fiber Distributed Data Interface
By Stephen Bucaro
The Fiber Distributed Data Interface (FDDI) standard was designed

by the American National Standards Institute (ANSI X3T9.5

standard ) in the mid-1980s, and later turned over to the

International Organization for Standardization (ISO). The OSI

specification for FDDI is not actually a single specification, but a

collection of four specifications for the the physical and media-access

portions of the OSI reference model.
FDDI uses pulses of light and fiber optic cable to send signals with a

100 Mbps throughput. It uses a token passing routine similar to

Token Ring networks, except that it uses two rings with signals

flowing in opposite directions (referred to as counter-rotating).
The purpose of the dual rings is to provide high reliability. The dual

rings consist of a primary ring and a secondary ring. During normal

operation, the primary ring is used for data transmission, while the

secondary ring remains idle. If the primary ring experience problems,

the secondary ring will take over data transmission.
FDDI can use two types of fiber optic cable,
single-mode
or

multimode
. A
mode
is a variation in the intensity of the light in the

cable. basically, a mode can be thought of as a ray of light. Single-
mode fiber allows only one mode of light to propagate through the

fiber. Multimode cable allows multiple modes of light to propagate

through the fiber.
Because multiple modes of light will arrive at the end of the fiber at

different times, a characteristic referred to as
modal dispersion
, the

bandwidth and distances that can be achieved using multimode fibers

is limited. Because only one mode of light is allowed to propagate

through Single-mode fiber, modal dispersion is not present. Single-
mode fiber is capable of achieving higher throughput over longer

distances.
The number of modes that a fiber-optic cable exhibits depends on the

dimensions and variation of refractive indices of the core and cladding

of the cable. Multimode fiber systems use an LED as the light

generating device, while single- mode fiber systems use lasers.
Fiber optic media has several advantages over copper media.

Because fiber optic does not emit electrical signals, it cannot be

tapped to permit unauthorized access to the data being transmitted.

Fiber optic is also immune to electrical interference allowing it to

support higher throughput than copper. For these reasons FDDI is

frequently used as a high speed backbone for large networks.
Contents
System Area Network Interface Cards
By Stephen Bucaro
In organizations with large critical mission networks, servers are

arranged in
clusters
. In a cluster servers are configured to share

resources such as storage and processing as if they were a single

more powerful server. If a server in a cluster fails, the other servers

in the cluster take over for it and continue processing (called "fail-
over").
Servers in a cluster can be configured to communicate with each

other the standard network, but in order to achieve the high level of

performance required, they usually communicate with each other

directly over a separate higher speed and higher reliability
System

Area Network
.
Whereas the standard network may use twisted-pair cabling, the

System Area Network may use separate fiber-optic cabling.
System

Area Network
interface cards are special high speed circuits that

provide communications between the servers over the
System Area

Network
.
If there are only two servers in a cluster, their System Area Network

Interface Cards can be connected directly to each other by a cable. If

there are more than two servers, a special hub is used to provide the

connection.
Contents
CompTIA Network+ Video Mentor
Get all the hands-on training you need to pass CompTIA’s latest

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master to pass the new CompTIA Network+ Exam (N10-004/JK0-
016). This DVD contains more than seven hours of expert-led videos

designed to build and test your knowledge of networking

technologies, media, topologies, devices, management, tools,

security, and a whole lot more!
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idea. Cost me $60. Includes 7 hours of step-by step instruction. Very

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explained things maybe half of the time, but didn't show things on

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take HIS class!
I also used the
Network+ Exam Cram book
, and by studying both I

passed the Network+ N10-004 exam easily. The exam isn't really

that hard. You just need to go slow, and think through the questions.

Plus, there are a lot of common sense safety and customer service

oriented questions. I would recommend using this video mentor along

with a book like the exam cram or something like it. You can't go

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Thorough coverage of all Network+ exam objectives:


Configuring IP addresses: subnets, gateways, DNS servers, NAT,

CIDR, and more


Utilizing today’s core network protocols, including IPv6


Configuring DHCP servers and connecting from Windows clients


Working with Cat 5e cable, NICs, multifunction devices, and other

network hardware


Setting up wireless access points, channels, frequencies, SSID, and

encryption


Identifying network topologies, connectors, and devices


Managing networks and monitoring their performance


Using Windows and Linux command-line network utilities


Setting up secure firewalls and VPNs, authenticating users, and

utilizing leading security protocols


And much more ...
Detailed lessons:
Each module begins with a succinct outline of

Network+ exam items covered that will be demonstrated in both the

lecture and lab portions of the videos.
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Walkthrough labs with the presenter to learn

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CLI Commands and GUI Operations:
Graphical interface and

command-line operations guide you through the task at hand.
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Contents
Network Administrator Street Smarts: A Real World Guide to

CompTIA Network+ Skills
Develop the skills you need in the real world
Hit the ground running with the street-smart training you'll find in

this practical book. Using a "year in the life" approach, it gives you an

inside look at network administration, with key information organized

around the actual day-to-day tasks, scenarios, and challenges you'll

face in the field. This valuable training tool is loaded with hands-on,

step-by-step exercises covering all phases of network administration,

including:


Designing a network


Implementing and configuring networks


Maintaining and securing networks


Troubleshooting a network
An invaluable study tool
This no-nonsense book also covers the common tasks that CompTIA

expects all its Network+ candidates to know how to perform. So

whether you're preparing for certification or seeking practical skills to

break into the field you'll find the instruction you need, including:


Choosing an Internet access technology


Configuring wireless components


Determining optimal placement of routers and servers


Setting up hubs, switches, and routers


Configuring a Windows(r) client


Troubleshooting your network
The book describes actual tasks that a network professional might be

required to perform, starting with a real world scenario, then defining

the scope of the task, the step-by-step procedure to performing the

task, and the criteria for completion. Below is a partial list of the

tasks described in the book:


Discovering and Filtering MAC Addresses


Developing an IP Addressing Scheme


Measuring Wireless Signal Strength


Using a Router as a Frame Relay Switch


Creating Local User Accounts


Creating Local User Groups


Managing Access to Resources


Setting Password Restrictions


Securing Links


Guarding Against SYN Flood Attacks


Implementing File-level Encryption


Using ARP Utilities


Using the Netstat Utility


Using ftp Utilities


Using Ping Utilities


Using the IPCONFIG Utility


Using Traceroute Utilities


Using Telnet


Using NSLOOKUP


Using a Protocol Analyzer


Displaying Computer Event logs
The Street Smarts series is designed to help current or aspiring IT

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Contents
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