Networks Questions UGC

8/19/2019 Networks Questions UGC

1/303

The _______ is the physical path over which a message travels.

Protocol,Medium,Signal,All the above

The information to be communicated in a data communications system is

the _______.

Medium,Protocol,Message,Transmission

Freuency of failure and networ! recovery time after a failure aremeasures of the _______ of a networ!.

Performance,"eliability, Security,Feasibility

An unauthori#ed user is a networ! _______ issue.

Performance,"eliability, Security,All the above

$hich topology reuires a central controller or hub%

Mesh,Star,&us,"ing

$hich topology reuires a multipoint connection%

A' Mesh

&' Star

(' &us

)' "ing


2/303

(ommunication between a computer and a !eyboard involves

______________ transmission.

Simple*,+alfduple*,Fullduple*,automatic

A television broadcast is an e*ample of _______ transmission.

A' simple*

&' halfduple*

(' fullduple*

)' automatic

A _______ connection provides a dedicated lin! between two devices.

Pointtopoint,Multipoint,Primary,Secondary

-n a _______ connection, more than two devices can share a single lin!.

A' pointtopoint

&' multipoint

(' primary

)' secondary

-n _______ transmission, the channel capacity is shared by both

communicating devices at all times.

A' simple*

&' halfduple*

(' fullduple*

)' halfsimple*


3/303

-n the original A"PA/T, _______ were directly connected together.

A' -MPs,+ost computers,etwor!s,"outers

This was the 0rst networ!.

A' (S/T,SF/T,AS/T,A"PA/T

$hich organi#ation has authority over interstate and international

commerce in the communications 0eld%

A' -T1T,-///,F((,-S2(

_______ are specialinterest groups that uic!ly test, evaluate, and

standardi#e new technologies.

A' Forums,"egulatory agencies,Standards organi#ations,All of the

above

$hich agency developed standards for physical connection interfaces and

electronic signaling speci0cations%

A' /-A,-T1T,AS-,-S2

_______ is the protocol suite for the current -nternet.

A' T(P3-P,(P,1-4,A(M

_______ refers to the structure or format of the data, meaning the order in

which they are presented.

A' Semantics,Synta*,Timing,All of the above


4/303

________ de0nes how a particular pattern to be interpreted, and what

action is to be ta!en based on that interpretation.

A' Semantics,Synta*,Timing,one of the above

_______ refers to two characteristics5 when data should be sent and how

fast it can be sent.

A' Semantics

&' Synta*

(' Timing

)' none of the above

)ata 6ow between two devices can occur in a _______ way.

A' Simple*,+alfduple*,Fullduple*,All of the above

-n a ______ connection, two and only two devices are connected by a

dedicated lin!.

A' Multipoint,Pointtopoint,7a' and 7b',one of the above

-n a ________ connection, three or more devices share a lin!.

A' Multipoint,

&' pointtopoint

(' 7a' and 7b'


______ refers to the physical or logical arrangement of a networ!.

A' )ata 6ow,Mode of operation,Topology,one of the above


5/303

)evices may be arranged in a _____ topology.

A' Mesh,"ing,&us,All of the above

A _______ is a data communication system within a building, plant, or

campus, or between nearby buildings.

A' MA,8A,$A,one of the above

A ______ is a data communication system spanning states, countries, or

the whole world.

A' MA

&' 8A

(' $A


________ is a collection of many separate networ!s.

A' A $A,An internet,A 8A,one of the above

There are ______________ -nternet service providers.

A' 8ocal,"egional,ational and international,All of the above

A ________ is a set of rules that governs data communication.

A' Forum,Protocol,Standard,one of the above


6/303

________ is an idea or concept that is a precursor to an -nternet standard.

A' "(F,"F(,-),one of the above

The -nternet model consists of _______ layers.

A' Three,Five,Seven,/ight

The processtoprocess delivery of the entire message is the responsibility

of the _______ layer.

A' etwor!,Transport,Application,Physical

The _______ layer is the layer closest to the transmission medium.

A' Physical,)ata lin!,etwor!,Transport

Mail services are available to networ! users through the _______ layer.

A' )ata lin!,Physical,Transport,Application

As the data pac!et moves from the upper to the lower layers, headers are

_______.

A' Added,"emoved,"earranged,Modi0ed

The _______ layer lies between the networ! layer and the application layer.

A' Physical,)ata lin!,Transport,one of the above

8ayer 9 lies between the physical layer and the _______ layer.


7/303

A' etwor!,)ata lin!,Transport,one of the above

$hen data are transmitted from device A to device &, the header from A:s

layer ; is read by &:s _______ layer.

A' Physical,Transport,Application,one of the above

The _______ layer changes bits into electromagnetic signals.


$hich of the following is an application layer service%

A' "emote login,File transfer and access,Mail service,All the above

$hy was the 2S- model developed%

A' Manufacturers disli!ed the T(P3-P protocol suite,The rate of data

transfer was increasing e*ponentially,Standards were needed to allow any two

systems to communicate,one of the above

The _______ model shows how the networ! functions of a computer ought

to be organi#ed.

A' ((-TT,2S-,-S2,AS-

The physical layer is concerned with the movement of _______ over the

physical medium.

A' Programs,)ialogs,Protocols,&its

The 2S- model consists of _______ layers.


8/303

A' Three,Five,Seven,/ight

-n the 2S- model, as a data pac!et moves from the lower to the upper

layers, headers are _______.

A' Added,"emoved,"earranged,Modi0ed

-n the 2S- model, when data is transmitted from device A to device &, the

header from A:s layer < is read by &:s _______ layer.

A' Physical,Transport,Session,Presentation

-n the 2S- model, what is the main function of the transport layer%

A' odetonode delivery,Processtoprocess message

delivery,Synchroni#ation,1pdating and maintenance of routing tables

-n the 2S- model, encryption and decryption are functions of the ________

layer.

A' Transport,Session,Presentation,Application

$hen a host on networ! A sends a message to a host on networ! &, which

address does the router loo! at%

A' Port,8ogical,Physical,one of the above

To deliver a message to the correct application program running on a host,

the _______ address must be consulted.

A' Port,-P,Physical,one of the above

-Pv= has _______ bit addresses.


9/303

A' >9,=;,?9@,ariable

-(MPv= includes _______.

A' -BMP,A"P,"A"P,a and b

The ______ layer is responsible for moving frames from one hop 7node' to

the ne*t.


The ______ layer adds a header to the pac!et coming from the upper layer

that includes the logical addresses of the sender and receiver.

A' Physical,)ata lin!,etwor!,one of the above

The_________ layer is responsible for the delivery of a message from one

process to another.

A' Physical,Transport,etwor!,one of the above

The -nternetwor!ing Protocol 7-P' is a ________ protocol.

A' "eliable,(onnectionoriented,&oth a and b,one of the above

_______ is a processtoprocess protocol that adds only port addresses,

chec!sum error control, and length information to the data from the upper layer.

A' T(P,1)P,-P,one of the above

__________ provides full transport layer services to applications.

A' T(P,1)P,A"P,one of the above


10/303

The ________ address, also !nown as the lin! address, is the address of a

node as de0ned by its 8A or $A.

A' Port,Physical,8ogical,one of the above

/thernet uses a ______ physical address that is imprinted on the networ!

interface card 7-('.

A' >9bit,=;bit,=byte,one of the above

A port address in T(P3-P is ______ bits long.

A' >9,;@,?=,one of the above

The ____ created a model called the 2pen Systems -nterconnection, which

allows diverse systems to communicate.

A' 2S-,-S2,-///,one of the above

The sevenlayer _____ model provides guidelines for the development of

universally compatible networ!ing protocols.

A' 2S-,-S2,-///,one of the above

The physical, data lin!, and networ! layers are the ______ support layers.

A' 1ser,etwor!,&oth 7a' and 7b',either 7a' nor 7b'

The session, presentation, and application layers are the ____ support

layers.


11/303

A' 1ser

&' networ!

(' both 7a' and 7b'

)' neither 7a' nor 7b'

The _______ layer lin!s the networ! support layers and the user support

layers.

A' Transport,etwor!,)ata lin!,Session

The _______ layer coordinates the functions reuired to transmit a bit

stream over a physical medium.

A' Transport,etwor!,)ata lin!,Physical

The _______ layer is responsible for delivering data units from one station

to the ne*t without errors.

A' transport

&' networ!

(' data lin!

)' physical

The ______ layer is responsible for the sourcetodestination delivery of a

pac!et across multiple networ! lin!s.

A' transport

&' networ!

(' data lin!

)' physical


12/303

The ________ layer is responsible for the processtoprocess delivery of the

entire message.

A' transport

&' networ!

(' data lin!

)' physical

The ______ layer establishes, maintains, and synchroni#es the interactions

between communicating devices.

A' Transport,etwor!,Session,Physical

The _______ layer ensures interoperability between communicating devices

through transformation of data into a mutually agreed upon format.

A' Transport,etwor!,)ata lin!,Presentation

The _________ layer enables the users to access the networ!.

A' Transport,Application,)ata lin!,Physical

T(P3-P is a ______ hierarchical protocol suite developed ____ the 2S- model.

A' SevenlayerC before,FivelayerC before,Si*layerC before,FivelayerC

after

The T(P3-P _______ layer is euivalent to the combined session,

presentation, and application layers of the 2S- model.


13/303

A' Application,etwor!,)ata lin!,Physical

The ________ address, also !nown as the lin! address, is the address of a

node as de0ned by its 8A or $A.

A' Physical,-P,Port,Speci0c

The ____ address uniuely de0nes a host on the -nternet.

A' Physical,-P,Port,Speci0c

The_____ address identi0es a process on a host.

A' physical

&' -P

(' port

)' speci0c

&efore data can be transmitted, they must be transformed to ________.

A' Periodic signals,/lectromagnetic signals,Aperiodic signals,8ow

freuency sine waves

A periodic signal completes one cycle in D.DD? s. $hat is the freuency%

A' ? +#,?DD +#,? E+#,? M+#

-n a freuencydomain plot, the hori#ontal a*is measures the ________.

A' Pea! amplitude,Freuency,Phase,Slope


14/303

-n a timedomain plot, the hori#ontal a*is is a measure of ________.

A' Signal amplitude,Freuency,Phase,Time

-f the bandwidth of a signal is < E+# and the lowest freuency is M+#,one of the above

As freuency increases, the period ________.

A' )ecreases,-ncreases,"emains the same,)oubles

Biven two sine waves A and &, if the freuency of A is twice that of &, then

the period of & is ________ that of A.

A' 2nehalf,Twice,The same as,-ndeterminate from

A sine wave is ________.

A' Periodic and continuous,Aperiodic and continuous,Periodic and

discrete,Aperiodic and discrete


15/303

-f the ma*imum amplitude of a sine wave is 9 , the minimum amplitude

is ________ .

A' 9,?,9,between 9 and 9

A signal is measured at two diGerent points. The power is P? at the 0rst

point and P9 at the second point. The d& is D. This means ________.

A' P9 is #ero,P9 euals P?,P9 is much larger than P?,P9 is much

smaller than P?

________ is a type of transmission impairment in which the signal loses

strength due to the resistance of the transmission medium.

A' Attenuation,)istortion,oise,)ecibel

________ is a type of transmission impairment in which the signal loses

strength due to the diGerent propagation speeds of each freuency that ma!esup the signal.

A' Attenuation

&' )istortion

(' oise

)' )ecibel

________ is a type of transmission impairment in which an outside source

such as crosstal! corrupts a signal.

A' Attenuation

&' )istortion

(' oise

)' )ecibel


16/303


17/303

_______ signals can have only a limited number of values.

A' Analog,)igital,7a' or 7b',one of the above

Freuency and period are ______.

A' -nverse of each other,Proportional to each other,The same,one of

the above

________is the rate of change with respect to time.

A' Amplitude,Time,Freuency,oltage

_______ describes the position of the waveform relative to time D.

A' Freuency,Phase,Amplitude,oltage

A sine wave in the ______ domain can be represented by one single spi!e

in the _____ domain.

A' TimeC freuency,FreuencyC time,TimeC phase,PhaseC time

A _________ sine wave is not useful in data communicationsC we need to

send a _______ signal.

A' (ompositeC singlefreuency,SinglefreuencyC composite,Single

freuencyC doublefreuency,one of the above

The _____ of a composite signal is the diGerence between the highest and

the lowest freuencies contained in that signal.

A' Freuency,Period,&andwidth,Amplitude


18/303

A7n'_________ signal is a composite analog signal with an in0nite

bandwidth.

A' )igital,Analog,/ither 7a' or 7b',either 7a' nor 7b'

&aseband transmission of a digital signal is possible only if we have a ____

channel.

A' 8owpass,&andpass,8ow rate,+igh rate

-f the available channel is a ____ channel, we cannot send a digital signal

directly to the channel.

A' lowpass

&' bandpass

(' low rate

)' high rate

For a ______ channel, the yuist bit rate formula de0nes the theoretical

ma*imum bit rate.

A' noisy

&' noiseless

(' bandpass

)' lowpass

For a ______ channel, we need to use the Shannon capacity to 0nd the

ma*imum bit rate.

A' oisy,oiseless,&andpass,8owpass

_________ can impair a signal.


19/303

A' Attenuation,)istortion,oise,All of the above

The _________ product de0nes the number of bits that can 0ll the lin!.

A' &andwidthperiod,Freuencyamplitude,&andwidthdelay,)elay

amplitude

1nipolar, bipolar, and polar encoding are types of _______ encoding.

A' 8ine,&loc!,"H,Manchester

_______ encoding has a transition at the middle of each bit.

A' "H,Manchester,)iGerential Manchester,All the above

_______ encoding has a transition at the beginning of each D bit.

A' "H,Manchester,)iGerential Manchester,All the above

P(M is an e*ample of _______ conversion.

A' )igitaltodigital,)igitaltoanalog,Analogtoanalog,Analogtodigital

-f the freuency spectrum of a signal has a bandwidth of


20/303

A' /ual to the lowest freuency of a signal,/ual to the highest

freuency of a signal,Twice the bandwidth of a signal,Twice the highest freuency

of a signal

$hich of the following encoding methods does not provide for

synchroni#ation%

A' "H8,"H,"H-,Manchester

$hich encoding method uses alternating positive and negative values for?s%

A' "H-,"H,Manchester,AM-

$hich uanti#ation level results in a more faithful reproduction of the

signal%

A' 9,@,?=,>9

&loc! coding can help in _______ at the receiver.

A' Synchroni#ation,/rror detection,Attenuation,7a' and 7b'

-n _______ transmission, bits are transmitted simultaneously, each across

its own wire.

A' Asynchronous serial,Synchronous serial,Parallel,7a' and 7b'

-n _______ transmission, bits are transmitted over a single wire, one at a

time.


21/303

A' Asynchronous serial,Synchronous serial,Parallel,7a' and 7b'

-n _______ transmission, a start bit and a stop bit frame a character byte.

A' asynchronous serial

&' synchronous serial

(' parallel

)' 7a' and 7b'

-n asynchronous transmission, the gap time between bytes is _______.

A' Fi*ed,ariable,A function of the data rate,Hero

___________ conversion involves three techniues5 line coding, bloc!

coding, and scrambling.

A' Analogtodigital,)igitaltoanalog,Analogtoanalog,)igitaltodigital

________ is the process of converting digital data to a digital signal.

A' &loc! coding,8ine coding,Scrambling,one of the above

A' &loc! coding

&' 8ine coding

(' Scrambling

)' one of the above


22/303

________ is normally referred to as m&3n& codingC it replaces each mbit

group with an nbit group.

A' &loc! coding,8ine coding,Scrambling,one of the above

________ provides synchroni#ation without increasing the number of bits.

A' Scrambling,8ine coding,&loc! coding,one of the above

Two common scrambling techniues are ________.

A' "H and "H,AM- and "H,&@HS and +)&>,Manchester and

diGerential Manchester

The most common techniue to change an analog signal to digital data is

called __________.

A' PA8,P(M,Sampling,one of the above

The 0rst step in P(M is ________.

A' Iuanti#ation,Modulation,Sampling,one of the above

There are three sampling methods5 __________.

A' Iuanti#ed, sampled, and ideal,-deal, sampled, and 6attop,-deal,natural, and 6attop,one of the above

______ 0nds the value of the signal amplitude for each sampleC ____ 0nds

the change from the previous sample.

A' )MC P(M,P(MC )M,)MC (M,one of the above


23/303

$hile there is 7are' only _____ way7s' to send parallel data, there is 7are'

three subclass7es' of serial transmission.

A' 2neC two,TwoC three,2neC three,one of the above

-n ______ transmission, we send ? start bit 7D' at the beginning and ? or

more stop bits 7?s' at the end of each byte.

A' Synchronous,Asynchronous,-sochronous,one of the above

-n _________ transmission, we send bits one after another without start or

stop bits or gaps. -t is the responsibility of the receiver to group the bits.

A' synchronous

&' asynchronous

(' isochronous


The ________ mode provides synchroni#ation for the entire stream of bits

must. -n other words, it guarantees that the data arrive at a 0*ed rate.

A' synchronous

&' asynchronous

(' isochronous


A _________ digital signal includes timing information in the data being

transmitted.

A' Selfsynchroni#ing,Selfmodulated,Selftransmitted,one of the

above


24/303

-n decoding a digital signal, the receiver calculates a running average of

the received signal power, called the _______.

A' &aseline,&ase,8ine,one of the above

The ________ rate de0nes the number of data elements sent in ?sC the

______ rate is the number of signal elements sent in ?s.

A' )ataC signal,SignalC data,&audC bit,one of the above

The signal rate is sometimes called the ____ rate.

A' &aud,&it,Signal,one of the above

The data rate is sometimes called the ___ rate.

A' &aud,&it,Signal,one of the above

-n a _____ scheme, all the signal levels are on one side of the time a*is,

either above or below.

A' Polar,&ipolar,1nipolar,All of the above

-n ______ schemes, the voltages are on the both sides of the time a*is. For

e*ample, the voltage level for D can be positive and the voltage level for ? can

be negative.

A' polar

&' bipolar

(' unipolar

)' all of the above


25/303

-n _____, the level of the voltage determines the value of the bit.

A' "H-,"H8,&oth 7a' and 7b',either 7a' nor 7b'

-n ______, the change or lac! of change in the level of the voltage

determines the value of the bit.

A' "H-

&' "H8

(' both 7a' and 7b'


The idea of "H and the idea of "H8 are combined into the ________

scheme.

A' Manchester,)iGerential Manchester,&oth 7a' and 7b',either 7a' nor

7b'

The idea of "H and the idea of "H- are combined into the ________

scheme.

A' Manchester

&' diGerential Manchester

(' both 7a' and 7b'


-n _______ encoding, the duration of the bit is divided into two halves. The

voltage remains at one level during the 0rst half and moves to the other level inthe second half. The transition at the middle of the bit provides synchroni#ation.

A' Manchester


(' both 7a' and 7b'



26/303

-n ___________ there is always a transition at the middle of the bit, but the

bit values are determined at the beginning of the bit. -f the ne*t bit is D, there is

a transitionC if the ne*t bit is ?, there is none.

A' Manchester


(' both 7a' and 7b'


-n Manchester and diGerential Manchester encoding, the transition at the

middle of the bit is used for __________.

A' &it transfer,&aud transfer,Synchroni#ation,one of the above

The minimum bandwidth of Manchester and diGerential Manchester is ____

that of "H.

A' The same as,Twice,Thrice,one of the above

-n _______encoding, we use three levels5 positive, #ero, and negative.

A' 1nipolar,&ipolar,Polar,one of the above

The _____ scheme uses data patterns of si#e 9 and encodes the 9bit

patterns as one signal element belonging to a fourlevel signal.

A' ;&,one of the above

The ______ scheme uses three levels 7J, D, and ' and three transition

rules to move between the levels.

A' ;&



27/303

______ substitutes eight consecutive #eros with DDD&D&.

A' &;&@,+)&>,&@HS,one of the above

______ substitutes four consecutive #eros with DDD or &DD

A' &;&@,+)&>,&@HSf,one of the above

ASE, PSE, FSE, and IAM are e*amples of ________ conversion.


AM and FM are e*amples of ________ conversion.


> -n IAM, both ________ of a carrier freuency are varied.

A' Freuency and amplitude,Phase and freuency,Amplitude and

phase,one of the above

; -f the baud rate is ;DD for a IPSE signal, the bit rate is ________ bps.

A' ?DD,;DD,@DD,?=DDa

< -f the bit rate for an ASE signal is ?9DD bps, the baud rate is ________.

A' >DD,;DD,=DD,?9DD

= -f the bit rate for an FSE signal is ?9DD bps, the baud rate is ________.


28/303

A' >DD

&' ;DD

(' =DD

)' ?9DD

-f the bit rate for a ?=IAM signal is ;DDD bps, what is the baud rate%

A' >DD

&' ;DD

(' ?DDD

)' ?9DD

@ -f the baud rate for a =;IAM signal is 9DDD, what is the bit rate%

A' >DD

&' ;DD

(' ?DDD

)' ?9DDD

K Biven an AM radio signal with a bandwidth of ?D E+# and the highest

freuency component at D< E+#, what is the freuency of the carrier signal%

A' DD E+#,D< E+#,?D E+#,(annot be determined from given

information

?D _______ conversion is the process of changing one of the characteristics of

an analog signal based on the information in the digital data.

A' )igitaltoanalog,Analogtoanalog,Analogtodigital,)igitaltodigital


29/303

?? $hich of the following is not a digitaltoanalog conversion%

A' ASE,PSE,FSE,AM

?9 -n ________, the amplitude of the carrier signal is varied to create signal

elements. &oth freuency and phase remain constant.

A' ASE,PSE,

(' FSE

)' IAM

?> -n _________, the freuency of the carrier signal is varied to represent data.

&oth pea! amplitude and phase remain constant.

A' ASE

&' PSE

(' FSE

)' IAM

?; -n ________, the phase of the carrier is varied to represent two or more

diGerent signal elements. &oth pea! amplitude and freuency remain constant.

A' ASE

&' PSE

(' FSE

)' IAM


30/303

?< A constellation diagram shows us the __________ of a signal element,

particularly when we are using two carriers 7one inphase and one uadrature'.

A' Amplitude and phase,Amplitude and freuency,Freuency and

phase,one of the above

?= Iuadrature amplitude modulation 7IAM' is a combination of ___________.

A' ASE and FSE,ASE and PSE,PSE and FSE,one of the above

? ________ uses two carriers, one inphase and the other uadrature.

A' ASE,PSE,FSE,IAM

?@ _________ conversion is the representation of analog information by an

analog signal.

A' )igitaltoanalog,Analogtoanalog,Analogtodigital,)igitaltodigital

?K Analogtoanalog conversion is needed if the available bandwidth is

_______.

A' 8owpass,&andpass,/ither 7a' or 7b',either 7a' nor 7b'

9D $hich of the following is not an analogtoanalog conversion%

A' AM,PM,FM,IAM

9? -n _____ transmission, the carrier signal is modulated so that its amplitude

varies with the changing amplitudes of the modulating signal.


31/303

A' AM,PM,FM,one of the above

99 -n _____ transmission, the freuency of the carrier signal is modulated to

follow the changing voltage level 7amplitude' of the modulating signal. The pea!

amplitude and phase of the carrier signal remain constant, but as the amplitude

of the information signal changes, the freuency of the carrier changes

correspondingly.

A' AM

&' PM

(' FM


9> -n _____ transmission, the phase of the carrier signal is modulated to follow

the changing voltage level 7amplitude' of the modulating signal.

A' AM

&' PM

(' FM


9; -n _______, the pea! amplitude of one signal level is DC the other is the

same as the amplitude of the carrier freuency.

A' PSE,22E,FSE,one of the above

9< +ow many carrier freuencies are used in &ASE%

A' 9,?,D,one of the above


32/303

9= +ow many carrier freuencies are used in &FSE%

A' 9

&' ?

(' D


9 +ow many carrier freuencies are used in &PSE%

A' 9

&' ?

(' D


9@ +ow many carrier freuencies are used in IPSE%

A' 9

&' ?

(' D


9K The constellation diagram of &ASE has ______ dots.

A' 9

&' ?

(' D



33/303

>D The constellation diagram of &PSE has ______ dots.

A' 9

&' ?

(' D


>? The constellation diagram of IPSE has ______ dots.

A' 9

&' ?

(' ;


>9 The constellation diagram of ?=IAM has ______ dots.

A' ;,?=,@,one of the above

>> The Federal (ommunications (ommission 7F((' allows ______!+# for each

AM station.

A' ; The Federal (ommunications (ommission 7F((' allows ______ !+# for each

FM station.

A' 9D,?DD,9DD,one of the above

The sharing of a medium and its lin! by two or more devices is called

_______.

A' Modulation,/ncoding,8ine discipline,Multiple*ing


34/303

9 $hich multiple*ing techniue transmits analog signals%

A' F)M,T)M,$)M,7a' and 7c'

> $hich multiple*ing techniue transmits digital signals%

A' F)M,T)M,$)M,one of the above

; $hich multiple*ing techniue shifts each signal to a diGerent carrier

freuency%

A' F)M,T)M,&oth 7a' and 7b',one of the above

< -n synchronous T)M, for n signal sources of the same data rate, each

frame contains _______ slots.

A' n,n J ?,n L ?,D to n

= -n T)M, the transmission rate of the multiple*ed path is usually _______ the

sum of the transmission rates of the signal sources.

A' Breater than,8ess than,/ual to,ot related to

$hich multiple*ing techniue involves signals composed of light beams%



35/303

@ _________ utili#ation is the use of available bandwidth to achieve speci0c

goals.

A' Freuency,&andwidth,Amplitude,one of the above

K ________ can be achieved by using multiple*ingC ______ can be achieved by

using spreading.

A' /ciencyC privacy and antiNamming,Privacy and antiNammingC

eciency,Privacy and eciencyC antiNamming,/ciency and antiNammingC

privacy

?D ________ is the set of techniues that allows the simultaneous transmission

of multiple signals across a single data lin!.

A' )emodulating,Multiple*ing,(ompressing,one of the above

?? -n a multiple*ed system, __ lines share the bandwidth of ____ lin!.

A' ?C n,?C ?,nC ?,nC n

?9 The word ______ refers to the portion of a _______ that carries a

transmission.

A' (hannelC lin!,8in!C channel,8neC channel,8ineC lin!

?> ______ can be applied when the bandwidth of a lin! 7in hert#' is greater

than the combined bandwidths of the signals to be transmitted.

A' T)M,F)M,&oth 7a' or 7b',either 7a' or 7b'


36/303

?; FSM is an _________techniue.

A' Analog,)igital,/ither 7a' or 7b',one of the above

?< ____ is designed to use the high bandwidth capability of 0beroptic cable.


?= ______ is an analog multiple*ing techniue to combine optical signals.

A' F)M,

&' T)M

(' $)M

)' one of the above

? _____ is a digital process that allows several connections to share the highbandwidth of a lin!.

A' F)M,T)M,$)M

)' one of the above

?@ _____ is a digital multiple*ing techniue for combining several lowrate

channels into one highrate one.

A' F)M

&' T)M

(' $)M

)' one of the above


37/303

?K $e can divide ____ into two diGerent schemes5 synchronous or statistical.

A' F)M

&' T)M

(' $)M


9D -n ________ T)M, each input connection has an allotment in the output

even if it is not sending data.

A' Synchronous,Statistical,-sochronous,one of the above

9? -n ________ T)M, slots are dynamically allocated to improve bandwidth

eciency.

A' Synchronous,Statistical,-sochronous,one of the above

99 -n ________, we combine signals from diGerent sources to 0t into a larger

bandwidth.

A' Spread spectrum,8ine coding,&loc! coding,one of the above

9> _______ is designed to be used in wireless applications in which stationsmust be able to share the medium without interception by an eavesdropper and

without being subNect to Namming from a malicious intruder.

A' Spread spectrum,Multiple*ing,Modulation,one of the above.

9; The _______ techniue uses M diGerent carrier freuencies that are

modulated by the source signal. At one moment, the sign modulates one carrier

freuencyC at the ne*t moment, the signal modulates another carrier freuency.


38/303

A' F)M,)SSS,F+SS,T)M

9< The ______ techniue e*pands the bandwidth of a signal by replacing each

data bit with n bits.

A' F)M

&' )SSS

(' F+SS

)' T)M

?. transmission media are usually categori#ed as _______.

A' Fi*ed or un0*ed,Buided or unguided,)eterminate or

indeterminate,Metallic or nonmetallic

9 Transmission media lie below the _______ layer.

A' Physical,etwor!,Transport,Application

> _______ cable consists of an inner copper core and a second conducting

outer sheath.

A' Twistedpair,(oa*ial,Fiberoptic,Shielded twistedpair

; -n 0ber optics, the signal is _______ waves.

A' 8ight,"adio,-nfrared,ery lowfreuency

< $hich of the following primarily uses guided media%

A' (ellular telephone system,8ocal telephone system,Satellitecommunications,"adio broadcasting


39/303

= $hich of the following is not a guided medium%

A' Twistedpair cable,(oa*ial cable,Fiberoptic cable,Atmosphere

$hat is the maNor factor that ma!es coa*ial cable less susceptible to noise

than twistedpair cable%

A' -nner conductor,)iameter of cable,2uter conductor,-nsulating

material

@ -n an optical 0ber, the inner core is _______ the cladding.

A' )enser than,8ess dense than,The same density as,Another name for

K The inner core of an optical 0ber is _______ in composition.

A' Blass or plastic,(opper,&imetallic,8iuid

?D $hen a beam of light travels through media of two diGerent densities, if

the angle of incidence is greater than the critical angle, _______ occurs.

A' "e6ection,"efraction,-ncidence,(riticism

?? $hen the angle of incidence is _______ the critical angle, the light beam

bends along the interface.

A' More than,8ess than,/ual to,one of the above


40/303

?9 Signals with a freuency below 9 M+# use _______ propagation.

A' Bround,S!y,8ineofsight,one of the above

?> Signals with a freuency between 9 M+# and >D M+# use ______

propagation.

A' Bround,S!y,8ineofsight,one of the above

?; Signals with a freuency above >D M+# use _______propagation.

A' ground

&' s!y

(' lineofsight


?< A parabolic dish antenna is a7n' _______ antenna.

A' 2mnidirectional,&idirectional,1nidirectional,+orn

?= A7n' _____ medium provides a physical conduit from one device to another.

A' Buided,1nguided,/ither 7a' or 7b',one of the above

?

A' (oa*ial,Fiberoptic,Twistedpair,one of the above

?@ _______ cable is used for voice and data communications.


41/303

A' (oa*ial,Fiberoptic,Twistedpair,one of the above

?K __________ consists of a central conductor and a shield.

A' (oa*ial

&' Fiberoptic

(' Twistedpair


9D _____ cable can carry signals of higher freuency ranges than _____ cable.

A' TwistedpairC Fiberoptic,(oa*ialC 0beroptic,(oa*ialC twisted

pair,one of the above

9? ______ cables are composed of a glass or plastic inner core surrounded by

cladding, all encased in an outside Nac!et.

A' (oa*ial,Fiberoptic

(' Twistedpair


99 ______ cables carry data signals in the form of light.

A' (oa*ial

&' Fiberoptic

(' Twistedpair



42/303

9> -n a 0beroptic cable, the signal is propagated along the inner core by

_______.

A' "e6ection,"efraction,Modulation,one of the above

9; _________ media transport electromagnetic waves without the use of a

physical conductor.

A' Buided, 1nguided,/ither 7a' or 7b',one of the above

9< "adio waves are _________.

A' 2mnidirectional,1nidirectional,&idirectional,one of the above

9= Microwaves are _________.

A' omnidirectional

&' unidirectional

(' bidirectional


9 _______ are used for cellular phone, satellite, and wireless 8A

communications.

A' "adio waves,Microwaves,-nfrared waves,one of the above

9@ ________ are used for shortrange communications such as those between

a P( and a peripheral device.

A' "adio waves

&' Microwaves


43/303

(' -nfrared waves


Traditionally, _____ methods of switching have been important.

A' Four,Three,Five,Si*

9 $e can divide today:s networ!s into ____ broad categories.

A' four

&' three

(' 0ve

)' two

> Pac!etswitched networ!s can also be divided into ______subcategories5

virtualcircuit networ!s and datagram networ!s

A' Four,Three,Two,Five

; A ________ networ! is made of a set of switches connected by physical

lin!s, in which each lin! is divided into n channels.

A' 8ineswitched,Frameswitched,(ircuitswitched,one of the above

< (ircuit switching ta!es place at the ________ layer.

A' )ata line,Physical,etwor!,Transport

= -n _______, the resources need to be reserved during the setup phaseC the

resources remain dedicated for the entire duration of data transfer phase untilthe teardown phase.


44/303

A' )atagram switching,(ircuit switching,Frame switching,one of the

above

-n _________, there is no resource allocation for a pac!et.

A' datagram switching

&' circuit switching

(' frame switching


@ -n _________, resources are allocated on demand.



(' frame switching


K -n __________, each pac!et is treated independently of all others.



(' frame switching


?D -n _______ there are no setup or teardown phases.



(' frame switching


45/303


?? A _________ networ! is a cross between a circuitswitched networ! and a

datagram networ!. -t has some characteristics of both.

A' irtualcircuit,Pac!etswitched,Frameswitched,one of the above

?9 $e can say that a pac!et switch has _______ types of components.

A' Two,Three,Four,one of the above

?> The simplest type of switching fabric is the ______ switch.

A' (rosspoint,(rossbar,TS-,STS

?; A ________ switch is a multistage switch with microswitches at each stage

that route the pac!ets based on the output port represented as a binary string.

A' (rossbar,TS-,&anyan,one of the above

?< -n a banyan switch, for @ inputs and @ outputs, we have _____ stages.

A' @,;,>,9

?= -n a banyan switch, for @ inputs and @ outputs, we have _____

microswitches at each stage.

A' @

&' ;


46/303

(' >

)' 9

? A ________ switch combines spacedivision and timedivision technologies

to ta!e advantage of the best of both.

A' TST,SSS,TTT,one of the above

?@ The most popular technology in timedivision switching is called the

_________.

A' ST-,-TS,TS-,one of the above

?K &ased on the (los criteria, if O 9DD, then n must be eual to or greater

than ____.

A' ?D,9D,>D,;D

9D &ased on the (los criteria, if O 9DD, then ! must be eual to or greater

than ____.

A' 9?,?K,>?,;?

9? &ased on the (los criteria, if O 9DD, then the minimum number of

crosspoints is greater than or eual to _______.

A' ?


47/303

A' ?DDDD,9DDDD,;DDDD,>DDDD

9> -n a threestage space division switch, if O 9DD, the number of

crosspoints is ______.

A' ;DDDD,Breater than ;DDDD,8ess than ;DDDD,Breater than ?DDDDD

9; A ________ switch combines crossbar switches in several 7normally three'

stages.

A' Multistage,Multiple crossbar,Multiple path,one of the above

9< -n _______ switching, the paths in the circuit are separated from one

another spatially.

A' Timedivision,Spacedivision,Twodimensional,Threedimensional

9= A switched $A is normally implemented as a _______ networ!.

A' irtualcircuit,)atagram,(ircuitswitched,one of the above

9 -n a ________ networ!, two types of addressing are involved5 global andlocal.

A' irtualcircuit,)atagram,(ircuitswitched,one of the above

9@ The networ! layer in the -nternet is designed as a __________ networ!.

A' virtualcircuit

&' datagram


48/303

(' circuitswitched


9K A switch in a datagram networ! uses a routing table that is based on the

______ address.

A' Source,)estination,8ocal,one of the above

>D The _______ address in the header of a pac!et in a datagram networ!

normally remains the same during the entire Nourney of the pac!et.

A' Source,)estination,8ocal,one of the above

A local telephone networ! is an e*ample of a _______ networ!.

A' pac!etswitched

&' circuitswitched

(' messageswitched


9 The local loop has _______ cable that connects the subscriber telephone to

the nearest end oce.

A' twistedpair

&' coa*ial

(' 0beroptic


> )ata from a computer are _______C the local loop handles _______ signals.

A' analogC analog


49/303

&' analogC digital

(' digitalC digital

)' digitalC analog

; _______ is suitable for businesses that reuire comparable upstream and

downstream data rates.

A' )S8

&' A)S8

(' S)S8

)' 7a' and 7b'

< )MT is a modulation techniue that combines elements of _______ and

_______.

A' F)MC T)M

&' I)MC IAM

(' F)MC IAM

)' PSEC FSE

= The largest portion of the bandwidth for A)S8 carries _______.

A' voice communication

&' upstream data

(' downstream data

)' control data

_______ was designed as an alternative to the T? line.


50/303

A' )S8

&' A)S8

(' S)S8

)' +)S8

@ +)S8 encodes data using _______.

A' ;&3


51/303

A' PSE

&' IAM

(' P(M

)' ASE

?9 -n an +F( networ!, the upstream data are modulated using the _______

modulation techniue.

A' IAM

&' IPSE

(' P(M

)' ASE

?> The standard for data transmission over an +F( networ! is called _______.

A' M(S

&' )2(S-S

(' (MTS

)' A)S8

?; The original telephone networ!, which is referred to as the plain old

telephone system 7P2TS', was an ________ system.

A' digital

&' analog

(' digital as well as analog



52/303

?< The modern telephone networ! is now ________.

A' digital

&' analog

(' digital as well as analog


?= The telephone networ! is made of ______ maNor components.

A' 9

&' >

(' ;


? The 1nited States is divided into many _______.

A' 8/(s

&' 8ATAs

(' -4(s


?@ The carrier that handles intra8ATA services is called a7n' _____ .

A' P2P

&' -4(

(' 8/(



53/303

?K The carrier that handles inter8ATA services is called a7n' _______.

A' P2P

&' -4(

(' 8/(


9D -n ______signaling, the same circuit is used for both signaling and data.

A' inband

&' outofband

(' mi*ed


9? -n ________signaling, a portion of the bandwidth is used for signaling and

another portion for data.

A' inband

&' outofband

(' mi*ed


99 The protocol that is used for signaling in the telephone networ! is called

______.

A' P2P

&' SSS

(' SS



54/303

9> Telephone companies provide two types of analog services5 analog _______

services and analog _____services.

A' switchedC inband

&' outofbandC inband

(' switchedC leased

)' leasedC outofband

9; The two most common digital services are ________ service and ______.

A' switched3


55/303

9 ______technology is a set of technologies develpoed by the telephone

companies to provide high data rate transmission.

A' AS8

&' )S8

(' 8)S


9@ The traditional cable T system used ________cable end to end.

A' twistedpair

&' coa*ial

(' 0beroptic


9K The second generation of cable networ!s is called a7n' _________ networ!.

A' +F(

&' +(F

(' (F+


>D The +F( networ! uses _______ cable.

A' twistedpair

&' coa*ial

(' 0beroptic

)' a combination of 7b' and 7c'


56/303

>? To use a cable networ! for data transmission, we need two !ey devices5 a

______ and a _________

A' (MC (MS

&' (TC (MTS

(' (MC (MTS


$hich error detection method uses one:s complement arithmetic%

A' Simple parity chec!

&' Twodimensional parity chec!

(' ("(

)' (hec!sum

9 $hich error detection method consists of Nust one redundant bit per data

unit%

A' Simple parity chec!

&' Twodimensional parity chec!

(' ("(

)' (hec!sum

> -n cyclic redundancy chec!ing, what is the ("(%

A' The divisor

&' The uotient

(' The dividend

)' The remainder


57/303

; -n cyclic redundancy chec!ing, the divisor is _______ the ("(.

A' The same si#e as

&' one bit less than

(' one bit more than


< A burst error means that two or more bits in the data unit have changed.

A' doublebit

&' burst

(' singlebit


= -n ________ error correction, the receiver corrects errors without reuestingretransmission.

A' bac!ward

&' onward

(' forward


-n ________ error correction, the receiver as!s the sender to send the data

again.

A' bac!ward

&' retransmission

(' forward



58/303

@ $e can divide coding schemes into two broad categories5 ________ and

______coding.

A' bloc!C linear

&' linearC nonlinear

(' bloc!C convolution


K -n modulo9 arithmetic, __________ give the same results.

A' addition and multiplication

&' addition and division

(' addition and subtraction


?D -n modulo9 arithmetic, we use the ______ operation for both addition and

subtraction.

A' 42"

&' 2"

(' A)


?? -n _____ coding, we divide our message into bloc!s, each of ! bits, called

___.

A' bloc!C bloc!words

&' linearC datawords


59/303


60/303

A' <

&' =

(' ??


?= -n a linear bloc! code, the _______ of any two valid codewords creates

another valid codeword.

A' 42"ing

&' 2"ing

(' A)ing


? A simple paritychec! code can detect __________ errors.

A' an evennumber of

&' two

(' no errors

)' an oddnumber of

?@ _______codes are special linear bloc! codes with one e*tra property. -f a

codeword is rotated, the result is another codeword.

A' onlinear

&' (onvolution

(' (yclic



61/303

?K The _____of errors is more dicult than the ______.

A' correctionC detection

&' detectionC correction

(' creationC correction

)' creationC detection

9D -n modulo?? arithmetic, we use only the integers in the range ______,

inclusive.

A' ? to ?D

&' ? to ??

(' D to ?D


9? -n modulo9 arithmetic, we use only ______.

A' ? and 9

&' D and 9

(' D and ?


99 Adding ? and ? in modulo9 arithmetic results in _________.

A' ?

&' 9

(' D



62/303

9> -n bloc! coding, if ! O9 and n O>, we have _______ invalid codewords.

A' @

&' ;

(' 9


9; The +amming distance between eual codewords is _________.

A' ?

&' n

(' D


9< The +amming distance between ?DD and DD? is ________.

A' 9

&' D

(' ?


9= -n bloc! coding, if n O

(' <



63/303

9 -f the +amming distance between a dataword and the corresponding

codeword is three, there are _____ bits in error.

A' >

&' ;

(' <


9@ The _______ of a polynomial is the highest power in the polynomial.

A' range

&' degree

(' power


9K The divisor in a cyclic code is normally called the _________.

A' degree

&' generator

(' redundancy


>D A generator that contains a factor of ____ can detect all oddnumbered

errors.

A' *

&' * J ?

(' ?



64/303

>? (hec!sums use _________ arithmetic.

A' two:s complement arithmetic

&' one:s complement arithmetic

(' either 7a' or 7b'


>9 -n one:s complement arithmetic, if positive is D???, then negative is

________.

A' ????

&' ??D?

(' ?DDD


>> The chec!sum of ???? and ???? is _________.

A' ????

&' DDDD

(' ???D

)' D???

>; The chec!sum of DDDD and DDDD is __________.

A' ????

&' DDDD

(' ???D

)' D???


65/303

? -n a Bo&ac! A"I, if the window si#e is =>, what is the range of

seuence numbers%

A' D to =>

&' D to =;

(' ? to =>

)' ? to =;

9 -n Bo&ac! A"I, if frames ;, A"I stands for _______.

A' Automatic repeat uanti#ation

&' Automatic repeat reuest

(' Automatic retransmission reuest

)' Ac!nowledge repeat reuest

; For Stopand$ait A"I, for ?D data pac!ets sent, _______

ac!nowledgments are needed.

A' e*actly ?D

&' less than ?D

(' more than ?D



66/303

< +)8( is an acronym for _______.

A' +ighduple* line communication

&' +ighlevel data lin! control

(' +alfduple* digital lin! combination

)' +ost doublelevel circuit

= )ata lin! control deals with the design and procedures for ______communication.

A' nodetonode

&' hosttohost

(' processtoprocess


_______ in the data lin! layer separates a message from one source to a

destination, or from other messages going from other sources to other

destinations.

A' )igiti#ing

&' (ontrolling

(' Framing


@ -n _______ framing, there is no need for de0ning the boundaries of frames.

A' 0*edsi#e

&' variablesi#e


67/303

(' standard


K -n ________ framing, we need a delimiter 76ag' to de0ne the boundary of

two frames.

A' 0*edsi#e

&' variablesi#e

(' standard


?D _________framing uses two categories of protocols5 characteroriented and

bitoriented.

A' Fi*edsi#e

&' ariablesi#e

(' Standard

)' one of the above

?? -n a ________ protocol, the data section of a frame is a seuence of

characters.

A' bitoriented

&' characteroriented



?9 -n a _________ protocol, the data section of a frame is a seuence of bits.


68/303

A' byteoriented

&' bitoriented



?> -n _________ protocols, we use ________.

A' characterorientedC byte stung

&' characterorientedC bit stung

(' bitorientedC character stung


?; &yte stung means adding a special byte to the data section of the frame

when there is a character with the same pattern as the ______.

A' header

&' trailer

(' 6ag


?< -n ________ protocols, we use ________.

A' byteorientedC bit stung

&' characterorientedC bit stung

(' bitorientedC bit stung



69/303

?= &it stung means adding an e*tra D to the data section of the frame when

there is a seuence of bits with the same pattern as the ________.

A' header

&' trailer

(' 6ag


? _______ control refers to a set of procedures used to restrict the amount of

data that the sender can send before waiting for ac!nowledgment.

A' Flow

&' /rror

(' Transmission


?@ ______ control refers to methods of error detection and correction.

A' Flow

&' /rror

(' Transmission


?K The Simplest Protocol and the Stopand$ait Protocol are for ______

channels.

A' noisy

&' noiseless




70/303

9D The StopAnd$ait A"I, Bo&ac! A"I, and the Selective "epeat A"I

are for ______ channels.

A' noisy

&' noiseless



9? The ____ Protocol has neither 6ow nor error control.

A' Stopand$ait

&' Simplest

(' Bo&ac! A"I

)' Selective"epeat A"I

99 The _______Protocol has 6ow control, but not error control.

A' Stopand$ait

&' Simplest

(' Bo&ac! A"I


9> The _______Protocol has both 6ow control and error control.

A' Stopand$ait

&' Bo&ac! A"I

(' Selective"epeat A"I

)' both 7b' and 7c'


71/303

9; -n the _____ Protocol, the sender sends its frames one after another with no

regard to the receiver.

A' Stopand$ait

&' Simplest

(' Bo&ac! A"I


9< -n the _____ Protocol, the sender sends one frame, stops until it receives

con0rmation from the receiver, and then sends the ne*t frame.

A' Stopand$ait

&' Simplest

(' Bo&ac! A"I


9= The _________Protocol, adds a simple error control mechanism to the

_______Protocol.

A' Stopand$ait A"IC Stopand$ait

&' Bo&ac! A"IC Stopand$ait

(' Selective "epeat A"IC Bo&ac! A"I


9 -n the _________Protocol, if no ac!nowledgment for a frame has arrived, we

resend all outstanding frames.

A' Stopand$ait A"I

&' Bo&ac! A"I


72/303



9@ -n the _________ protocol we avoid unnecessary transmission by sending

only frames that are corrupted.

A' Stopand$ait A"I

&' Bo&ac! A"I



9K &oth Bo&ac! and Selective"epeat Protocols use a _________.

A' sliding frame

&' sliding window

(' sliding pac!et


>D -n Bo&ac! A"I, if < is the number of bits for the seuence number,

then the ma*imum si#e of the send window must be _____

A' ?<

&' ?=

(' >?

)' ?

>? -n Bo&ac! A"I, if < is the number of bits for the seuence number,

then the ma*imum si#e of the receive window must be _____


73/303

A' ?<

&' ?=

(' >?

)' ?

>9 -n Selective "epeat A"I, if < is the number of bits for the seuence

number, then the ma*imum si#e of the send window must be _____

A' ?<

&' ?=

(' >?

)' ?

>> -n Selective "epeat A"I, if < is the number of bits for the seuence

number, then the ma*imum si#e of the receive window must be _____

A' ?<

&' ?=

(' >?

)' ?

>; +ighlevel )ata 8in! (ontrol 7+)8(' is a _______ protocol for

communication over pointtopoint and multipoint lin!s.

A' bitoriented

&' byteoriented

(' characteroriented



74/303

>< The most common protocol for pointtopoint access is the PointtoPoint

Protocol 7PPP', which is a _________protocol.

A' bitoriented

&' byteoriented

(' characteroriented


>= _______ control refers to a set of procedures used to restrict the amount of

data that the sender can send before waiting for ac!nowledgment.

A' Flow

&' /rror

(' Transmission


> _________control in the data lin! layer is based on automatic repeat

reuest, which is the retransmission of data.

A' Flow

&' /rror

(' Transmission


>@ -n Stopand$ait A"I, we use seuence numbers to number the frames.

The seuence numbers are based on __________arithmetic.

A' modulo9

&' modulo;

(' modulom


75/303


>K -n Stopand$ait A"I, the ac!nowledgment number always announces in

______ arithmetic the seuence number of the ne*t frame e*pected.

A' modulo9

&' modulo;

(' modulom


;D -n the Bo&ac! Protocol, if the si#e of the seuence number 0eld is @, the

seuence numbers are in ________ arithmetic,

A' modulo9

&' modulo @

(' modulo9


76/303

&' "M

(' A"M

)' &M

;> -n _________, the con0guration is balanced. The lin! is pointtopoint, and

each station can function as a primary and a secondary.

A' A&M

&' "M

(' A"M

)' &M

;; -n PPP, the ________ is responsible for establishing, maintaining,

con0guring, and terminating lin!s.

A' (P

&' 8(P

(' (+AP

)' PAP

;< -n PPP, ________ is a simple authentication procedure with a twostep

process5

A' (P

&' 8(P

(' (+AP

)' PAP


77/303

;= -n PPP, _______ is a threeway handsha!ing authentication protocol in

which the password is !ept secretC it is never sent online.

A' (P

&' 8(P

(' (+AP

)' PAP

-n ________ each station sends a frame whenever it has a frame to send.

A' pure A82+A

&' slotted A82+A

(' both 7a' and 7b'


9 -n pure A82+A, the vulnerable time is ______ the frame transmission time.

A' the same as

&' two times

(' three times


> The ma*imum throughput for pure A82+A is ________ per cent.

A' ?9.9

&' ?@.;

(' >=.@


; -n __________, each station is forced to send only at the beginning of the

time slot.


78/303

A' pure A82+A

&' slotted A82+A

(' both 7a' and 7b'


< -n slotted A82+A, the vulnerable time is ______ the frame transmission

time.

A' the same as

&' two times

(' three times


= The ma*imum throughput for pure A82+A is ________ per cent.

A' ?9.9

&' ?@.;

(' >=.@


The vulnerable time for (SMA is the ________propagation time.

A' the same as

&' two times

(' three times



79/303

@ -n the _________ method, after the station 0nds the line idle, it sends its

frame immediately. -f the line is not idle, it continuously senses the line until it

0nds it idle.

A' nonpersistent

&' ?persistent

(' ppersistent


K -n the ________method, a station that has a frame to send senses the line.

-f the line is idle, it sends immediately. -f the line is not idle, it waits a randomamount of time and then senses the line again.

A' nonpersistent

&' ?persistent

(' ppersistent


?D -n the _______method, after the station 0nds the line idle it sends or refrain

from sending based on the outcome of a random number generator. -f the line is

busy, it tries again.

A' nonpersistent

&' ?persistent

(' ppersistent


?? $e have categori#ed access methods into _______ groups.

A' two

&' three

(' four


80/303

)' 0ve

?9 -n ___________ methods, no station is superior to another station and none

is assigned the control over another.

A' random access

&' controlled access

(' channeli#ation


?> -n ______, the chance of collision can be reduced if a station senses the

medium before trying to use it.

A' MA

&' (SMA

(' F)MA

)' ()MA

?; ________ reuires that each station 0rst listen to the medium before

sending.

A' MA

&' (SMA

(' F)MA

)' ()MA

?< __________ augments the (SMA algorithm to detect collision.

A' (SMA3(A


81/303

&' (SMA3()


)' both 7a' and 7b'

?= -n ________, a station monitors the medium after it sends a frame to see if

the transmission was successful. -f so, the station is 0nished. -f, however, there is

a collision, the frame is sent again.

A' (SMA3(A

&' (SMA3()


)' both 7a' and 7b'

? To avoid collisions on wireless networ!s, ________was invented.

A' (SMA3(A

&' (SMA3()


)' both 7a' and 7b'

?@ -n _______, collisions are avoided through the use of three strategies5 the

interframe space, the contention window, and ac!nowledgments.

A' (SMA3(A

&' (SMA3()


)' both 7a' and 7b'


82/303

?K -n _______ methods, the stations consult one another to 0nd which station

has the right to send.

A' random access


(' channeli#ation


9D -n _______ methods, a station cannot send unless it has been authori#ed by

other stations.

A' random access


(' channeli#ation


9? $e discussed ______ popular controlledaccess methods.

A' two

&' three

(' four


99 -n the ________ method, a station needs to ma!e a reservation before

sending data. Time is divided into intervals.

A' reservation

&' polling

(' to!en passing



83/303

9> -n the _____ method, time is divided into intervals. -n each interval, a

reservation frame precedes the data frames sent in that interval.

A' reservation

&' polling

(' to!en passing


9; -n the ______ method, all data e*changes must be made through the

primary device even when the ultimate destination is a secondary device.

A' reservation

&' polling

(' to!en passing


9< -n the _______ method, the primary device controls the lin!C the secondary

devices follow its instructions.

A' reservation

&' polling

(' to!en passing


9= -n the _______ method, the stations in a networ! are organi#ed in a logical

ring.

A' reservation

&' polling


84/303

(' to!en passing


9 -n the _______ method, each station has a predecessor and a successor.

A' reservation

&' polling

(' to!en passing


9@ -n the _________ method, a special pac!et called a ______ circulates through

the ring.

A' reservation5 control frame

&' polling5 poll reuest

(' to!en passing5 to!en


9K _________ is a multipleaccess method in which the available bandwidth of

a lin! is shared in time, freuency, or through code, between diGerent stations.

A' "andom access

&' (ontrolled access

(' (hanneli#ation


>D $e discussed ________ channeli#ation protocols.

A' two


85/303

&' three

(' four


>? -n ________, the available bandwidth is divided into freuency bands.

A' F)MA

&' T)MA

(' ()MA


>9 -n ______, each station is allocated a band to send its data. -n other words,

each band is reserved for a speci0c station, and it belongs to the station all the

time.

A' F)MA

&' T)MA

(' ()MA


>> -n _______, the stations share the bandwidth of the channel in time.

A' F)MA

&' T)MA

(' ()MA



86/303

>; -n _____, each station is allocated a time slot during which it can send data.

/ach station transmits its data in its assigned time slot.

A' F)MA

&' T)MA

(' ()MA


>< -n _____, each station transmits its data in its assigned time slot.

A' F)MA

&' T)MA

(' ()MA


>= -n ______, the stations use diGerent codes to achieve multiple access.

A' F)MA

&' T)MA

(' ()MA


> _______ is based on coding theory and uses seuences of numbers called

chips.

A' F)MA

&' T)MA

(' ()MA



87/303

>@ -n _______, the seuences are generated using orthogonal codes such the

$alsh tables.

A' F)MA

&' T)MA

(' ()MA


$hat is the he*adecimal euivalent of the /thernet address D?D??D?D DDD?DDD?

D?D?D?D? DDD??DDD ?D?D?D?D DDDD????%

A'


88/303

; $hich of the following could not be an /thernet unicast destination%

A' ;>5&5=(5)/5?D5DD

&' ;;5AA5(?59>5;9

(' ;=5


89/303

@ The _______ layer of /thernet consists of the 88( sublayer and the MA(

sublayer.

A' data lin!

&' physical

(' networ!


K The _____ sublayer is responsible for the operation of the (SMA3() access

method and framing.

A' 88(

&' M--

(' MA(


?D /ach station on an /thernet networ! has a uniue _______ address

imprinted on its networ! interface card 7-('.

A' 9

&' @D

(' ?9@


90/303


?9 The ma*imum frame length for ?DMbps /thernet is ________ bytes.

A' ?


91/303

)' ?D&aseF

?= ________ uses 0beroptic cable.

A' ?D&ase<

&' ?D&ase9

(' ?D&aseT

)' ?D&aseF

? Fast /thernet has a data rate of ________Mbps.

A' ?D

&' ?DD

(' ?DDD

)' ?D,DDD

?@ -n _________, autonegotiation allows two devices to negotiate the mode or

data rate of operation.

A' Standard

&' Fast /thernet

(' Bigabit /thernet

)' TenBigabit /thernet

?K __________ uses two pairs of twistedpair cable.

A' ?DD&aseT4

&' ?DD&aseF4

(' ?DD&aseT;


92/303


9D _________ uses two 0beroptic cables.

A' ?DD&aseT4

&' ?DD&aseF4

(' ?DD&aseT;


9? _________ uses four pairs of voicegrade, or higher, twistedpair cable.

A' ?DD&aseT4

&' ?DD&aseF4

(' ?DD&aseT;


99 Bigabit /thernet has a data rate of ________Mbps.

A' ?D

&' ?DD

(' ?DDD

)' ?D,DDD

9> Bigabit /thernet access methods include _______ mode.

A' halfduple*

&' fullduple*

(' both 7a' and 7b'


93/303


9; __________ uses two optical 0bers and a shortwave laser source,

A' ?DDD&aseS4

&' ?DDD&ase84

(' ?DDD&aseT


9< __________uses two optical 0bers and a longwave laser source.

A' ?DDD&aseS4

&' ?DDD&ase84

(' ?DDD&aseT


9= __________ uses four twisted pairs.

A' ?DDD&aseS4

&' ?DDD&ase84

(' ?DDD&aseT


9 ________ uses shortwave @


94/303


9@ ________uses longwave ?>?Dnm single mode 0ber.

A' ?DB&aseS

&' ?DB&ase8

(' ?DB&ase/


9K ________ uses ?D -n /thernet addressing, if the least signi0cant bit of the 0rst byte is D, the

address is _________.

A' unicast

&' multicast

(' broadcast


>? -n /thernet addressing, if the least signi0cant bit of the 0rst byte is ?, the

address is _________.

A' unicast

&' multicast


95/303

(' broadcast


>9 -n /thernet addressing, if all the bits are ?s, the address is _________.

A' unicast

&' multicast

(' broadcast


>> ______de0nes a protocol data unit 7P)1' that is somewhat similar to that of

+)8(.

A' MA(

&' 88(

(' 881


>; The purpose of the _______ is to provide 6ow and error control for the

upperlayer protocols that actually demand these services

A' MA(

&' 88(

(' 881


>< -n the /thernet, the _______0eld is actually added at the physical layer and

is not 7formally' part of the frame.


96/303


97/303

A' ;&3

)' Manchester

;? ?DDD&aseS4, ?DDD&ase84, and ?DDD&ase(4 use _________ bloc! coding

and ________ line coding.

A' ;&3


98/303

&' -/// @D9.<

(' -/// @D9.??

)' -/// @D9.9

9 -n -/// @D9.??, a ___ is made of stationary or mobile wireless stations and

an optional central base station, !nown as the access point 7AP'.

A' /SS

&' &SS

(' (SS


> -n -/// @D9.??, a &SS without an AP is called an _________.

A' an ad hoc architecture

&' an infrastructure networ!



; -n -/// @D9.??, a &SS with an AP is sometimes referred to as ____________.

A' an ad hoc architecture

&' an infrastructure networ!



< -n -/// @D9.??, communication between two stations in two diGerent &SSs

usually occurs via two ________.


99/303

A' &SSs

&' /SSs

(' APs


= -n -/// @D9.??, a station with ________ mobility is either stationary 7not

moving' or moving only inside a &SS.

A' notransition

&' &SStransition

(' /SStransition


-n -/// @D9.??, a station with ________mobility can move from one &SS to

another, but the movement is con0ned inside one /SS.

A' notransition

&' &SStransition

(' /SStransition


@ -n -/// @D9.??, a station with ________ mobility can move from one /SS to

another.

A' notransition

&' &SStransition

(' /SStransition



100/303

K -n -/// @D9.??, _______ is an optional access method that can be

implemented in an infrastructure networ! 7not in an ad hoc networ!'.

A' )(F

&' P(F



?D -n -/// @D9.??, when a frame is going from one station in a &SS to another

without passing through the distribution system, the address 6ag is _____

A' DD

&' D?

(' ?D

)' ??

?? -n -/// @D9.??, when a frame is coming from an AP and going to a station,

the address 6ag is _______.

A' DD

&' D?

(' ?D

)' ??

?9 -n -/// @D9.??, when a frame is going from a station to an AP, the address

6ag is _____.

A' DD

&' D?

(' ?D


101/303

)' ??

?> -n -/// @D9.??, when a frame is going from one AP to another AP in a

wireless distribution system, the address 6ag is _____

A' DD

&' D?

(' ?D

)' ??

?; The -/// @D9.?? standard for wireless 8As de0nes two services5 ______

and _______.

A' &SSC ASS

&' /SSC SSS

(' &SSC /SS

)' &SSC )(F

?< -n -/// @D9.??, the access method used in the )(F sublayer is _________.

A' A82+A

&' (SMA3(A

(' (SMA3()


?= -n -/// @D9.??, the access method used in the P(F sublayer is ______.

A' contention

&' controlled


102/303

(' polling


? -n -/// @D9.??, the ______ is a timer used for collision avoidance.

A' A

&' &SS

(' /SS


?@ -n -/// @D9.??, the MA( layer frame has ______ 0elds.

A' four

&' 0ve

(' si*


?K -n -/// @D9.??, the addressing mechanism can include up to

______addresses.

A' four

&' 0ve

(' si*


9D The original -/// @D9.??, uses _________.

A' F+SS

&' )SSS


103/303

(' 2F)M

)' either 7a' or 7b'

9? The -/// @D9.??a, uses _________.

A' F+SS

&' )SSS

(' 2F)M


99 The -/// @D9.??b, uses _________.

A' F+SS

&' )SSS

(' 2F)M


9> The -/// @D9.??g, uses _________.

A' F+SS

&' )SSS

(' 2F)M


9; The original -/// @D9.??, has a data rate of _____Mbps.

A' ?

&' =


104/303

(' ??

)' 99

9< -/// @D9.??a, has a data rate of _____Mbps.

A' ?

&' 9

(' =


9= -/// @D9.??b, has a data rate of _____Mbps.

A' ?

&' 9

('


105/303

(' si*


9K &luetooth is a _______ technology that connects devices 7called gadgets' in

a small area.

A' wired 8A

&' wireless 8A

(' 8A


>D A &luetooth networ! is called a ________.

A' piconet

&' scatternet

(' bluenet


>? -n &luetooth, multiple ________ form a networ! called a _________.

A' scatternetC piconets

&' piconets5 scatternet

(' piconets5 bluenet

)' bluenetC scatternet

>9 A &luetooth networ! consists of _____ primary device7s' and up to ____

secondary devices.

A' oneC 0ve


106/303

&' 0veC three

(' twoC si*

)' oneC seven

>> The "TS and (TS frames in (SMA3(A ____ solve the hidden station

problem. The "TS and (TS frames in (SMA3(A ____ solve the e*posed station

problem.

A' canC cannot

&' cannotC can

(' canC can

)' cannotC cannot

>; -n &luetooth, the current data rate is ____Mbps

A' 9

&' <

(' ??


>< -n &luetooth, the _______ layer is roughly euivalent to the physical layer of

the -nternet model.

A' radio

&' baseband

(' 89(AP



107/303

>= -n &luetooth, the _____layer is roughly euivalent to the MA( sublayer in

8As.

A' radio

&' baseband

(' 89(AP


> -n &luetooth, the 89(AP sublayer, is roughly euivalent to the 88( sublayer

in 8As.

A' radio

&' baseband

(' 89(AP


>@ The access method in &luetooth is ________.

A' F)MA

&' T))T)MA

(' ()MA


>K -n &luetooth, the _____ lin! is used when avoiding latency 7delay in data

delivery' is more important than integrity 7errorfree delivery'.

A' S(2

&' A(8

(' A(2

)' S(8


108/303

;D -n &luetooth, the _____ lin! is used when data integrity is more important

than avoiding latency.

A' S(2

&' A(8

(' A(2

)' S(8

;? &luetooth uses ______method in the physical layer to avoid interference

from other devices or other networ!s.

A' )SSS

&' F+SS

(' F)MA


A repeater is a connecting device that operates in the _______ layer of the

-nternet model.

A' physical

&' data lin!

(' networ!

)' all of the above

9 A _______ regenerates a signal, connects segments of a 8A, and has no

0ltering capability.

A' repeater

&' bridge

(' router



109/303

> A _______ is a connecting device that operates in the physical and data lin!

layers of the -nternet model.

A' repeater

&' bridge

(' router


; A ________ bridge can forward and 0lter frames and automatically build its

forwarding table.

A' simple

&' dual

(' transparent


< A bridge can use the _________ algorithm to create a loopless topology.

A' binary tree

&' spanning tree

(' multiway tree


= A _______ 8A allows several 8As to be connected.

A' bac!bone

&' wireless

(' wired


110/303


A bac!bone is usually a ______.

A' bus

&' star



@ A virtual local area networ! 78A' is con0gured by _________.

A' software

&' physical wiring

(' hardware


K Membership in a 8A can be based on _________.

A' port numbers

&' MA( addresses

(' -P addresses

)' all of the above

?D 8As can_________.

A' reduce networ! trac

&' provide an e*tra measure of security



111/303

)' both 7a' and 7b'

?? _________ is Nust a connector.

A' An active hub

&' A passive hub



?9 -n a startopology /thernet 8A, _______ is Nust a point where the signals

coming from diGerent stations collideC it is the collision point.

A' An active hub

&' A passive hub



?> ________ is part of the mediaC its location in the -nternet model is below the

physical layer.

A' An active hub

&' A passive hub



?; A _______ is a device that operates only in the physical layer.

A' passive hub

&' repeater


112/303

(' bridge

)' router

?< A ________receives a signal and, before it becomes too wea! or corrupted,

regenerates the original bit pattern. -t then sends the refreshed signal.

A' passive hub

&' repeater

(' bridge

)' router

?= A __________ forwards every frameC it has no 0ltering capability.

A' passive hub

&' repeater

(' bridge

)' router

? ________ is actually a multiport repeater. -t is normally used to create

connections between stations i

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