Incorrect answers and explanations: A is incorrect because UDP is the User Datagram Protocol, which is a simple transport protocol and isn’t used to prevent looping on a network.. C is
Trang 1You have decided to implement redundant switches on your
net-9
work that will enable packets of data to take the best possible route
to its destination Which of the following features will you want
on the switches that will be used on this network so that looping doesn’t occur?
A STP
B UDP
C TCP
D IDS
Correct answer and explanation: A STP is Spanning Tree Protocol, which
was designed to prevent broadcast storms that result from looping When a switch has more than one way to communicate with a node, it can cause broadcasts to go out across more than one path This can create a loop in the way this data travels across the network The Spanning Tree Protocol uses
an algorithm that identifies that a switch has multiple ways of communicat-ing with a scommunicat-ingle node
Incorrect answers and explanations: A is incorrect because UDP is the
User Datagram Protocol, which is a simple transport protocol and isn’t
used to prevent looping on a network B is incorrect because TCP is the Transmission Control Protocol and isn’t used for preventing looping C is
incorrect because an IDS is an Intrusion Detection System
You have installed new cabling to accommodate a new section of
10
the building that is being networked Once computers are installed, you find that they are unable to connect to the network You believe the problem is that the length of the cabling has exceeded the maximum distance allowed You want to fix the problem with the least amount of cost and work Which of the following will you do?
A Remove the cabling and install cable that supports a longer distance
B Install a passive hub to increase the distance that data can travel along the cable
C Install a NIC to increase the distance that data can travel along the cable
D Install a switch to increase the distance that data can travel along the cable
Correct answer and explanation: D Install a switch to increase the
dis-tance that data can travel along the cable Switches have the capability to regenerate data so that data can travel over longer distances along cabling
Trang 2Incorrect answers and explanations: A is incorrect because the scenario
states that new cabling has just been installed B is incorrect because a passive
hub will not regenerate the data being passed across the hub C is incorrect
because a NIC provides computers and devices with access to a network but is
not used to regenerate data so that it can be transmitted over longer distances
A computer wants to send data to another computer on the network
11
Before it can send the data, it must send its credentials to a server
that verifies that it has access Which of the following is being used?
A Port authentication
B Port mirroring
C VLAN
D Trunking
Correct answer and explanation: A Port authentication requires a client
authenticating to a server before it is given access to a port This provides an
additional layer of security in clients being able to send data across a network
Incorrect answers and explanations: B is incorrect because port mirroring is
used to allow all the data sent and received on one port or VLAN to be copied
to another port C is incorrect because a VLAN is a virtual LAN, which is used
to make computers in different locations appear to be part of the same local
area network In doing so, broadcast messages can be sent to all computers
and devices that are part of the same VLAN, because they are part of the same
broadcast domain D is incorrect because trunking is used to allow two or
more VLANs to communicate with one another across a single network link
You want to have computers in different buildings to be part of the
12
same broadcast domain so that when a computer sends a broadcast
message, all the computers in that domain will receive it What
will you do to achieve this?
A Use a switch to establish a bridge between the two networks
B Use port mirroring to have the broadcast sent to computers in
the other building
C Implement a VLAN so that all computers can be part of the
same VLAN and receive broadcasts
D Use trunking to connect the two networks together
Correct answer and explanation: C A VLAN is a virtual LAN, which is
used to make computers in different locations appear to be part of the same
local area network In doing so, broadcast messages can be sent to all
com-puters and devices that are part of the same VLAN because they are part of
the same broadcast domain
Trang 3Incorrect answers and explanations: A is incorrect because multiport
bridg-ing wouldn’t make the computers in different buildbridg-ings part of the same
broadcast domain B is incorrect because port mirroring is used to allow all
the data sent and received on one port or VLAN to be copied to another port
D is incorrect because trunking is used to allow two or more VLANs to
com-municate with one another across a single network link
A client is attempting to send data across a port that requires
13
authentication In attempting to send data across the network in this situation, what role does the client play?
A Supplicant
B Authenticator
C Authentication server
D File server
Correct answer and explanation: A The supplicant is a client that wishes
access to the network and is attempting to use the port on a switch using port authentication This may be a computer, software, or network device that requires access to the network
Incorrect answers and explanations: B is incorrect because the
authentica-tor is the port that is configured to restrict access and requires authentication
before allowing access C is incorrect because the authentication server verifies
the credentials of the supplicant and determines if access should be granted or
denied D is incorrect because the file server is simply storing a copy of the file
you want to access and isn’t part of the port authentication process
You have set up several VLANs on your network You want to have
14
computers that are part of the same VLAN that are in different buildings connected by a single network link Which of the follow-ing will you use to implement this?
A Multiport bridging
B STP
C Create a new VLAN that will incorporate the different comput-ers you want connected together as part of the same VLAN
D Use trunking to connect the two virtual networks together
Correct answer and explanation: D Use trunking to connect the two
VLANs together Trunking is used to allow two or more VLANs to commu-nicate with one another across a single network link
Incorrect answers and explanations: A is incorrect because multiport
bridg-ing is another term for a switch, which can connect different LANs together
Trang 4in the same way a bridge would B is incorrect because STP is Spanning
Tree Protocol, which was designed to prevent broadcast storms that result
from looping C is incorrect because the computers you want to connect are
already part of a VLAN
A client is attempting to send data across a port that requires
15
authentication In attempting to send data across the network in
this situation, what role does the port play?
A Supplicant
B Authenticator
C Authentication server
D File server
Correct answer and explanation: B The authenticator is the port that is
con-figured to restrict access and requires authentication before allowing access
Incorrect answers and explanations: A is incorrect because a supplicant is
a client that wishes access to the network and is attempting to use the port
on a switch using port authentication This may be a computer, software, or
network device that requires access to the network C is incorrect because
the authentication server verifies the credentials of the supplicant and
deter-mines if access should be granted or denied D is incorrect because the file
server is simply storing a copy of the file you want to access and isn’t part of
the port authentication process
ChApTEr 5: wIrElESS NETworKING
You have a wireless network that has been in place for several years
1
Your users still are using 802.11b network cards in several systems
to connect to this wireless network Your company has decided to
update the wireless network to accommodate higher speeds Which
one of the following standards could you implement in your upgrade?
A 802.11a
B 802.11b
C 802.11g
D 802.11n
Correct answer and explanation: C and D Backwards compatibility with
802.11b can be maintained by implementing 802.11g or 802.11n Of note,
the overall wireless system will run slower with 802.11b clients still using
the access point
Trang 5Incorrect answers and explanations: A and B Answer A is incorrect,
802.11b and 802.11a run on different frequencies and therefore do not
inter-operate Answer B is incorrect as they are currently running this standard.
What technology does the 802.11n networks use to achieve great
2
speed?
A WPA
B 802.1X
C WEP
D MIMO (Multiple Input/Multiple Output)
Correct Answer and Explanation: D 802.11n uses MIMO utilizing more
than one antenna to achieve greater speed
Incorrect answers and explanations: A, B, and C Answer A is incorrect, WPA is a wireless encryption protocol Answer B is incorrect as this is a wireless authentication protocol Answer C is incorrect This is a wireless
encryption protocol
You are running a wireless network using 802.11g You fear that
3
someone might eavesdrop on your confidential information What protocols could you use to protect your wireless network?
A WPA
B 802.1X
C WEP
D MIMO (Multiple Input/Multiple Output)
Correct answer and explanation: A and C The older of the wireless
encryp-tion protocols is WEP, and the newer version is called WPA
Incorrect answers and explanations: B and D Answer B is incorrect as this is a wireless authentication protocol Answer D is incorrect This is
used by 802.11n to achieve greater speeds
You are about to implement a new wireless network Your
com-4
pany has a whole room filled with 2.4 GHz cordless phones What standard of 802.11 would you implement to reduce inter-ference?
A 802.11a
B 802.11b
C 802.11g
D 802.11n
Trang 6Correct answer and explanation: A 802.11a uses frequencies in the 5-GHz
range instead of 2.4 GHz
Incorrect answers and explanations: B, C, and D Answer B is incorrect as
this uses the 2.4-GHz range Answer C is incorrect as this uses the 2.4-GHz
range Answer D is incorrect as this uses both 2.4 GHz and 5 GHz.
You are a user in a company that would like to connect to the
5
company’s wireless network What information must you know in
order to connect to the wireless network?
A Username
B Password
C SSID
D Frequency
Correct answer and explanation: C In order to connect to a wireless
net-work, you must know the SSID or name of that wireless network You may
be able to pick it from a list as seen in Figure 5.21
FIGurE 5.21 Vista Connect to a Network.
Trang 7Incorrect answers and explanations: A, B, and D Answer A is incorrect;
you will not need to provide a username unless you are using RADIUS
authentication Answer B is incorrect; you would only have to provide a
password for RADIUS authentication or if you are using WEP or WPA
Answer D is incorrect The frequency is set for each standard such as
802.11a, or 802.11g
You are a user in a company that would like to connect to the
com-6
pany’s wireless network The company uses APs for connection to the corporate LAN What mode should your wireless connection be set to attach to WAPs?
A Ad hoc
B Secure
C Infrastructure
D WPA
Correct answer and explanation: C When you connect to wireless access
points, your connection should be set for infrastructure mode
Incorrect answers and explanations: A, B, and D Answer A is incorrect Ad hoc is for computer to computer connection Answer B is incorrect; though a
secure connection would be good, this is not a mode for wireless connection
Answer D is incorrect; WPA is an encryption protocol and not a mode.
You and a friend are at home and would like to share a few files
7
between your two computers What mode should you set your wireless card to make the connection?
A Ad hoc
B Secure
C Infrastructure
D WPA
Correct answer and explanation: A For computer to computer connection,
you need to implement an Ad hoc network
Incorrect answers and explanations: B, C, and D Answer B is incorrect;
a secure network is good, but not a mode that you can set your network
card to Answer C is incorrect; infrastructure is used when making a con-nection to a WAP Answer D is incorrect as WPA is a wireless encryption
protocol
You have heard that there is a way to make a connection to a
8
network printer without using a cable You would like to make this
Trang 8connection not using radio waves but instead using light pulses
What technology could allow you to make a connection to a printer
this way?
A 802.11b
B IrDA
C Bluetooth
D 802.11g
Correct answer and explanation: B An Infrared connection uses light
pulses instead of radio waves in order to connect Printers often have a
port for Infrared connection Incorrect answers and explanations: A, C,
and D Answer A is incorrect; 802.11b uses radio waves for its connection
Answer C is incorrect; bluetooth uses radio waves for its connection
Answer D is incorrect; 802.11g uses radio waves for its connection.
You are a user who would like to connect your PDA to your
com-9
puter using a wireless technology The PDA has several different
types of networks available You would like to use the technology
that only allows for a short distance connection
A 802.11b
B IrDA
C Bluetooth
D 802.11g
Correct answer and explanation: C A bluetooth connection only can make
a connection over a short distance (13–30 feet)
Incorrect answers and explanations: A, B, and D Answer A is incorrect;
802.11b has a distance of approximately 200 feet Answer B is incorrect as
most PDAs do not have an Infrared connection available Answer D is
incor-rect; 802.11 g has a distance of approximately 200 feet
You would like to make a secure connection to the corporate
wire-10
less network What must you possess to implement WEP for your
machine? You are a user who would like to connect your PDA to
your computer using a wireless technology The PDA has several
different types of networks available You would like to use the
technology that only allows for a short distance connection
A Username
B Password
C PassKey
D Certificate
Trang 9Correct answer and explanation: C A connection using WEP requires the
use of a Pre-Shared PassKey that both the access point and your computer are configured with
Incorrect answers and explanations: A, B, and D Answer A is incorrect; WEP does not need a username Answer B is incorrect as WEP does not need
a password but the PassKey Answer D is incorrect, as a certificate is not used
for WEP connection
You are troubleshooting a wireless 802.11b connection
Periodi-11
cally, your computer loses connection What could be the cause of this issue?
A Interference
B Incorrect username
C Incorrect encryption type
D Incorrect mode
Correct answer and explanation: A A connection has been established so
the most likely cause is interference from other 2.4 GHz devices
Incorrect answers and explanations: B, C, and D Answer B is incorrect,
you have already made a connection, so username would not be an issue
Answer C is incorrect as you have already made a connection, so encryption type would not be the problem Answer D is incorrect; since you are
connect-ing to an access point your mode would have to be set to infrastructure
You are a corporate user trying to connect to the company’s
wire-12
less network When you look at the list of available networks, you
do not find the corporate network listed What is most likely the cause?
A Wireless is turned off
B Incorrect mode
C Beaconing is turned off
D Interference
Correct answer and explanation: C In order to protect wireless networks,
often the SSID is not beaconed or sent out so wireless users can see it
In order to connect to this type of network, you must choose to connect manually, type in the SSID, and choose to connect even if the SSID is not broadcasting
Incorrect answers and explanations: A, B, and D Answer A is incorrect; wireless is working for other users so this would not be the case Answer B
is incorrect; computers can choose automatically between infrastructure and
Trang 10ad hoc Answer D is incorrect; interference would not cause the network to
not show up
You are having interference problems with devices that are using
13
the 2.4-Ghz frequency range Which standard would you choose to
avoid this interference?
A 802.11a
B 802.11b
C 802.11g
D 802.11n
Correct answers and explanation: A 802.11a uses the 5-GHz frequency
range
Incorrect answers and explanations: B, C, and D Answer B is
incor-rect; 802.11B uses the 2.4-GHz frequency range Answer C is incorrect as
802.11G uses the 2.4-GHz frequency range Answer D is incorrect; 802.11n
uses both the 2.4- and 5-GHz frequency ranges
You are a corporate user trying to connect to the company’s
wire-14
less network When you attempt to connect to the network, you are
denied being able to connect; what could be the cause?
A Wrong 802.11 standard
B Incorrect encryption type
C Bad username
D Interference
Correct answer and explanation: B If the wireless networking devices are
not set up for the same encryption, then the connection will be denied
Incorrect answers and explanations: A, C, and D Answer A is incorrect;
if you can see the network, then you are using the same 802.11 standard
Answer C is incorrect as usernames are only used with RADIUS
authen-tication Answer D is incorrect; interference would not cause the denied
connection
You are a corporate user trying to connect to the company’s
wire-15
less network You are within the distance limit of the wireless
network yet you are unable to find the network When you move
closer, the network then shows up What could be the cause?
A Structural interference between the AP and your machine
B Environmental interference such as electromagnetic
interference