Network+ Guide to Networks, 6th Edition

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Network+

Guide to Networks,
6
th

Edition


Solutions

6


1

Network+ Guide to Networks,
6
th Edition


Chapter 6 Solutions


Review Questions


1.

Which of the following utilities could you use to force the NIC on your Linux
server to use full
-
duplex transmission?

a.

ipconfig

b.

ifconfig

c.

iftool

d.

ethtool

2.

Which of the following
is a significant advantage to using an SFP interface on a
router rather than an on
-
board NIC?

a.

The SFP will be capable of higher throughputs.

b.

The SFP can be added or removed without affecting operations, thus
allowing for customization and future upgrades.

c.

The SFP can accept multiple types of connectors, allowing the router to
connect two disparate network types.

d.

The SFP promises greater security, as it can encrypt and decrypt data.

3.

Y
ou and a friend decide to set up Fast Ethernet networks in your respective
houses to

connect a half
-
dozen computers

at each location
. Both of you will
connect your networks to high
-
speed

Internet connections. As the connectivity
device for end nodes, you purchase a router,

whereas your friend
uses an old, but
Network+

Guide to Networks,
6
th

Edition


Solutions

6


2

functional,

12
-
port
hub

he found at a garage sale
. Which of the following will
your network

do that your friend’s network won’t do?

a.

Filter traffic based on IP address.

b.

Transmit data from any one of the connected computers to any other.

c.

Create a VLAN out of some of the compute
rs to isolate their transmissions
and

prevent them from affecting other connections.

d.

Allow other connectivity devices to be added to the network in the future.

4.

You are a network technician working on a 100Base
-
T network. A coworker has
been

having trouble
logging on to the server and asks whether you can quickly
tell her if her

workstation’s NIC is operating properly. You do not have the NIC’s
utility disk on

hand, but you look at the back of her workstation and learn that
although the NIC is

properly insta
lled and connected to the network, something’s
wrong with it. What

might you have seen that causes you to come to this
conclusion?

a.

Its activity LED is blinking green.

b.

Its loopback plug is improperly terminated.

c.

It has two types of receptacles

SC and RJ
-
45

and the wrong one is in
use.

d.

None of its LEDs are lit.

5.

How do bridges keep track of whether they should forward or filter frames?

a.

From each frame they receive, they extract source addresses; those frames
whose

s
ource addresses don’t belong to the bridge’s broadcast domain are
filtered.

Network+

Guide to Networks,
6
th

Edition


Solutions

6


3

b.

They hold each frame until it is requested by the destination node, at
which time the

bridge forwards the data to the correct segment based on
its MAC address.

c.

They maintain a filt
ering database that identifies which frames can be
filtered and which should be forwarded, based on their destination
MAC address.

d.

They compare the incoming frame’s network address to known addresses
on both

segments and filter those that don’t belong to e
ither.

6.

Which of the following
distinguishes switches from repeating devices, such as
hubs?

a.

Switches separate collision domains.

b.

Switches
separate broadcast domains
.

c.

Switches can alert the network administrator to high data collision rates.

d.

Switches do not
examine Network layer protocol information, which
makes them

faster

than repeating devices
.

7.

In cut
-
through switching, which frame field does the switch never read?

a.

Start frame delimiter

b.

Source address

c.

Frame check sequence

d.

Protocol type

8.

What potential probl
em does STP (Spanning Tree Protocol) address?

a.

An excess of erroneously short packets

b.

A broadcast storm

Network+

Guide to Networks,
6
th

Edition


Solutions

6


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c.

Network congestion due to a router failure

d.

Slow convergence time

9.

You are asked to configure a backbone switch that connects servers supplying
oceanic

and

atmospheric data to mariners and pilots around the world. Your
network’s traffic

load is very high at all times, day and night. What type of
switching do you configure

the switch to use?

a.

Bypass switching

b.

Store
-
and
-
forward switching

c.

Cut
-
through switching

d.

Message switching

10.

Suppose your company’s network contains two separate VLANs. Computer A is
on the

Customer Service VLAN and Computer B is on the Warehouse VLAN.
Besides a Layer 2

switch, what device is required for Computer A and Computer
B to exchange da
ta?

a.

Repeater

b.

Bridge

c.

Multiplexer

d.

Router

11.

In STP, what device acts as a guide to setting the best paths between switches?

a.

Root bridge

b.

Workgroup bridge

c.

Parent bridge

d.

Link bridge

Network+

Guide to Networks,
6
th

Edition


Solutions

6


5

12.

What switching technique allows you to funnel traffic belonging to more than one

V
LAN through a single switch interface?

a.

Jamming

b.

Route capturing

c.

Trunking

d.

Multiplexing

13.

Which of the following identifies the VLAN to which each piece of data belongs?

a.

A shim added to each packet’s header

b.

An envelope that encapsulates each packet

c.

A tag added
to each frame’s header

d.

A FCS added to each packet’s header

14.

Which of the following routing protocols is used on the Internet’s backbone?

a.

EIGRP

b.

OSPF

c.

BGP

d.

RIP

15.

Which of the following types of routing protocols allows routers to exchange
information about best p
aths with their neighboring routers only?

a.

Link
-
state

b.

Hybrid

c.

Distance
-
vector

d.

All of the above

16.

Why is a large, busy network more likely to use dynamic routing?

Network+

Guide to Networks,
6
th

Edition


Solutions

6


6

a.

Because dynamic routing is the default option on most routers, and it is
difficult to

configure
routers to use static routing

b.

Because dynamic routing is the only routing method compatible with the
BGP routing protocol, which is necessary for routing between WANs

c.

Because dynamic routing allows for stricter IP filtering and, therefore,
offers greater

d
ata security than static routing

d.

Because dynamic routing automatically selects the most efficient route
between nodes, reducing the possibility for human error

17.

A packet on a network using the RIP routing method has been passed from one
connectivity device
to another 15 times. What happens when it gets passed to one
more

device?

a.

It is returned to the node that originally transmitted it.

b.

It is encapsulated by the routing protocol and retransmitted.

c.

It is forwarded to its destination by the last device.


d.

It is

discarded.

18.

Which of the following factors is not considered when OSPF determines the best
path for a packet?

a.

Link failure

b.

Number of hops

c.

Throughput

d.

Latency

19.

Wh
at is a router’s convergence time?

a.

The time a router takes to interpret Layer 2 addressing information for any
Network+

Guide to Networks,
6
th

Edition


Solutions

6


7

given frame

b.

The maximum amount of time a router is allowed for choosing the best
path

c.

The time it takes for a router to recognize a best path in the event of a
change or network ou
tage


d.

T
he
time it takes for border routers to exchange routing table information

20.

At which layers of the OSI model are gateways capable of functioning?

a.

Layers 1 and 2

b.

Layers 2 and 3

c.

Layers 1, 2, and 3

d.

At all layers


Hands
-
On Projects


Project
6
-
1

In this project, students learn how to install a NIC on a Windows
7

workstation.

Steps 1


7: Students remove existing NIC drivers via the System
and Security window
.

Steps 8


9: Students physically install a new NIC in the computer and observe what
happe
ns when the computer boots up.

Step 10: If the NIC is installed properly, its LEDs (typically, green and orange) will blink
to indicate that it’s receiving power and exchanging traffic on the network (if it is
connected to the network properly). Conversel
y, if no LEDs are lit, the NIC is not
installed or connected properly.


Project
6
-
2

In this project students install drivers for the NIC they physically installed in Proj
ect 6
-
1.
Although the Windows

OS will automatically install a driver for most NICs, it
’s also
useful for students to learn how to install a new driver.

Students should refer to the
chapter text
for steps on installing NIC software. At the end of the project, students
should verify that their NIC is operating properly.

Network+

Guide to Networks,
6
th

Edition


Solutions

6


8


Project 6
-
3

In this p
roject,

students

create a simple VLAN on a Cisco switch using the IOS’s
command prompts. (Alternately, students could try using a Cisco IOS simulator such as
GNS3
.) At the end of the project, in Steps
21
-
28
, students connect a Windows 7
computer to the VLA
N port and assign it a static IP address to test whether their VLAN
works.


Case Projects


Case Project 6
-
1

Students should be aware that as long as they can log on to routers and switches,
they don’t need physical access to these devices to learn a lot about a network.
For instance, viewing routers’ access lists and routing tables will show how the
routers inte
rconnect with other routers, what routing protocols are in use, and
what types of clients and devices they accept connections from. The switches’
configurations will show VLAN configuration (including ports that belong to
each VLAN), switching methods, STP

settings, etc. Configurations on both types
of devices will show what connection speeds and access methods
are
in use.


Case Project 6
-
2

Students should create a simple network diagram that i
ncludes all the listed
hardware. Each piece of equipment should
be

labeled
. Each
location

should be
identified
. C
onnections between devices and connections between cl
ients and
connectivity devices should also be clearly identified.


Case Project 6
-
3

Students should explain how VLANs can separate traffic and therefore, contribute
to security for an isolated group of clients. Students should also understand that
routers will be necessary for the Accounting group’s VLAN to exchange data
with other client
s on the ConnectSpree network. In this project, students add to
the simple network

diagram they began in Case Project 6
-
2 to show the VLAN
and how it connects to the network backbone.


Case Project 6
-
4

Because it’s an ISP, ConnectSpree will rely on Interne
t connections with higher
bandwidth and
,

probably
,

redundant connections. This means edge routers will
also need the capacity to handle redundant connections and fast throughput

(at
Network+

Guide to Networks,
6
th

Edition


Solutions

6


9

least, and probably greater than, 1Gbps)
.
The ISP might also rely on multi
ple edge
routers. The routers will run BGP, rather than interior routing protocols, for
Internet connections. In addition to Internet gateways, the ISP might operate mail
gateways and gateways devoted to managing converged services, such as VoIP.