思科認證考試試題及答案5卷

思科認證考試試題及答案5卷第1卷

子網(wǎng)/22有（）個可用的IP地址

A.1022

B.1024

C.256

D.254

正確答案：A

備份路由器IOS的命令是：（）

A.copyflashtftp

B.copyrunning-configtftp

C.copyIOStftp

D.copystartup-configtftp

正確答案：A

CDPisbeingusedthroughouttheEzonexamnetwork.Whataretworeasons

whytheEzonexamnetworkadministratorwoulduseCDP?（Choosetwo）

A.Todeterminethestatusofnetworkservicesonaremotedevice

B.ToobtaintheIPAddressofaconnecteddeviceinordertotelnettothe

device

C.Toverifythetypeofcableinterconnectingtwodevices

D.ToverifyLayer2connectivitybetweentwodeviceswhenLayer3fails

E.ToobtainVLANinformationfromdirectlyconnectedswticehs

F.Todeterminethestatusoftheroutingprotocolsbetweendirectly

connectedrouters

G.Tosupportautomaticnetworkfailoverduringoutages

正確答案：BD

B,D

信息傳送時，RIP使用什么度量值來確定最佳路徑()

A.帶寬

B.跳數(shù)

C.管理距離

D.每個數(shù)據(jù)包發(fā)送的變量

正確答案：B

YouareworkingasanetworktechnicianatEzonexamUniversity,whenyou

getacallfromtheEngineeringFaculty.They'recomplainingthatthey'rereceiving

obsoleteinformationfromtheBusinessFaculty'snetworktrafficbroadcasts.

WhatcanyoudotocontaintheBusinessFaculty'sbroadcastwhilestill

keepingitconnectedtotheinternetandtheenterpriseservicesoftheUniversity?

(Selectallvalidanswerchoices)

A.Usehalfandfull-duplexEthernetontheEngineeringDepartmentLAN

B.EstablishaVTPdomaintominimizetheobsoletetraffic

C.ChangetheswitchIPaddressoftheswitch

D.CreateseparateVLANsandsubnetsforthetwodepartmentsandroute

betweenthetwo

E.ProvidegreaterbandwidthtotheEngineeringDepartmentLAN

F.Placethebusinessdepartmentonaseparatesubnetandroutebetween

networks

正確答案：DF

D,F解析：Explanation:

Inordertopreventthebroadcastandlinklevelmulticasttrafficseparated

betweenthedepartments,theyneedtobeisolatedatlayertwo.Thiscanbe

accomplishedintwoways.ThefirstistocreateseparateVLANsandplaceeach

departmentintoadifferentone.Thesecondmethodwouldbetoseparatethe

twodepartmentsintotwocompletelydifferentnetworks,androutebetween

them.

IncorrectAnswers:

A.Mixingtheuseofhalfandfullduplexwillmakenodifferencetothenumberof

broadcastssent.

B.TrunkingisonlyusefulinnetworksthatalreadycontainVLANs.

C.Thiswillmakenodifference,asalluserswillstillbecontainedwithinthesame

IPsubnet

E.Theamountofbandwidthinvolvedwillnothaveanyimpactontheamountof

broadcaststhataresentandreceived.

思科認證考試試題及答案5卷第2卷

交換機上VLAN的功能描述中，正確的是（）

A.可以減少廣播域的個數(shù)

B.可以減少廣播對網(wǎng)絡性能的影響

C.可以減少沖突域的個數(shù)

D.可以減小沖突域的容量

正確答案：B

AfterconnectingaPCtoanavailableportonaswitch,youfindthatthePC

cannotaccessanyoftheresourcesontheLAN.NootherPC'sconnectedtothe

switchappeartobehavinganyissues.Whatisthemostlikelycauseforthis

problem?

A.Therouterlacksaroutingtableentryforthenewhost

B.ThehostswitchportisassignedtotheincorrectVLAN

C.ThehostMACaddressisincorrectlyconfigured

D.ASTPinstanceforthenewhosthasnotbeeninitialized

E.TheswitchdoesnothavetheMACaddresshardcodedintheCAMtable.

正確答案：B

解析:Explanation:VirtualLANsbreakupbroadcastdomainsinalayer-

twoswitchedinternetwork.IfahostisinadifferentVLANthenthenetworkservicesitneed

stouse,thepacketsmustgothrougharouter.Ifroutingdoesnottakeplace,thePCwillbeu

nabletocommunicatewithanyotherdevicesnotinthesameVLAN.AnswerBisthebestan

swerforthisquestion.IncorrectAnswers:A.ThePCisunabletocommunicatewithotherL

ANusers.Norouterneedstoevenbeinstalledforthistowork.C,E.TheMACaddressofthe

PCdoesnotneedtobeenteredmanuallyintotheswitch.Theswitchwilldynamicallylearn

oftheMACaddressofthePC.D.TheSTPalgorithmdoesnotneedtohaveanyendhostinfo

rmationaddedinorderforittowork.

與動態(tài)路由協(xié)議相比，靜態(tài)路由有哪些優(yōu)點?()

A.帶寬占用少

B簡單

C.路由器能自動發(fā)現(xiàn)網(wǎng)絡拓撲變化

D.路由器能自動計算新的路由

正確答案：AB

BothbridgesareswitchesarebeingusedthroughouttheEzonexamLAN.

Whichofthefollowingstatementsaretrueregardingbridgesandswitchesinthis

network?

(Choose3)

A.Switchesareprimarilysoftwarebasedwhilebridgesarehardwarebased.

B.Switchesusuallyhaveahighernumberofportsthanmostbridges.

C.Bridgesarefrequentlyfasterthanswitches.

D.Bridgesdefinebroadcastdomainswhileswitchesdefinecollisiondomains.

E.BothbridgesandswitchesforwardLayer2broadcasts.

F.BothbridgesandswitchesmakeforwardingdecisionsbasedonLayer2

addresses.

正確答案：BEF

B,E,F

Barney是子網(wǎng)/24中一個具有IP地址的主機。以下哪些操作

時標準IPACL可配置來執(zhí)行的()

A.匹配準確的源IP地址

B.使用一個access-list命令匹配IP地址到,而不匹配其他IP

地址

C.使用一access-list命令匹配Barney的子網(wǎng)中的所有IP地址,而不匹配其

他IP地址

D.僅匹配包的目標IP地址

正確答案：AC

思科認證考試試題及答案5卷第3卷

AnewswitchisbeinginstalledintheEzonexamnetworkandyouhavebeen

assignedthetaskofconnectingittoanexistingswitch.Indoingthis,youwantto

setuptheVLANTrunkingProtocolsothatVLANinformationcanbepassed

betweentheswitches.Whichofthefollowingmustyoudotoaccomplishthis?

(Chooseallthatapply).

A.YoumustseteachendofthetrunklinetoIEEE802.Ieencapsulation.

B.YoumustsetthesameVTPmanagementdomainnameonboth

switches.

C.Youmustsetallportsonthetwoswitchesasaccessports.

D.YoumustconfigureoneoftheswitchesasaVTPserver.

E.Youmustusearollovercabletoconnectthetwoswitches.

正確答案：BD

解析：

Explanation:ThefollowingdescribeswhatisneededinordertocorrectlysetupVTP:Incor

rectAnswers:A.TheencapsulationcanbeeitherISLor802.1Q,andneedtomatchateache

ndofthetrunk.C.PortsmustonlybeassignedtoVLANS.Oncethatisdoneandthetrunkisu

pandrunning,theVLANinformationwillbepassedbetweentheswitches.E.AregularCA

T5cableisusedtoconnecttheswitches,assumingl0/100Ethernetisused.

Youareexperiencingintermittentissuesrelatingtocongestionwithinthe

Ezonexamnetwork.WhatarethepossiblecausesofcongestiononthisLAN?

(Chooseallthatapply)

A.Abroadcastdomainwithtoomanyhosts.

B.Fullduplexoperation.

C.Broadcaststorms.

D.Multicasting.

E.NetworkSegmentation.

F.Lowbandwidth.

正確答案：ACF

A,C,F解析：Explanation:

ALANsegmentwithtoomanyhostscanmeanthattherearealargenumberof

stationscontendingforbandwidth.Itcanalsomeananincreaseinthenumberof

collisionsonthesegment,whichcancausefurthercongestionissues.

Broadcaststormsaretheresultofalargenumberofbroadcastssentoverthe

LAN.Becauseeachstationlistenstothesebroadcastmessages,congestioncan

occurquickly.Finally,lowbandwidthcansimplymeanthattheLANcannot

processalloftheLANtrafficthatisbeingsent.ThiscanmeanthatTCPsessions

areretransmitted,whichcanleadtoadditionalcongestion.

IncorrectAnswers:

B.Thiscanalleviatecongestion,asdatacanbesentandreceivedatthesame

time.Inaddition,collisionsarenotpossibleinafullduplexLAN.

D.Multicastingcanactuallyalleviatecongestionissues,assinglestreamsof

informationcanreachmultiplehostsatthesametime,insteadofusingaseries

ofpointtopoint

connections.

E.SegmentationbreaksupalargeLANintomultiple,smallerLANS.Thiswill

meanfewerhostsperbroadcastdomain.

介質(zhì)lOOBaseT的最大傳輸距離是：（）

A.IOm

B.lOOm

C.lOOOm

D.500m

正確答案：B

WhichOSIlayerheadercontainstheaddressofadestinationhostthatison

anothernetwork?

A.Application

B.Presentation

C.Session

D.Transport

E.Network

F.Datalink

G.Physical

正確答案：E

E解析：Explanation:

Onlynetworkaddresscontainsthisinformation.Totransmitthepacketsthe

senderusesnetworkaddressanddatalinkaddress.Butthelayer2address

representsjusttheaddressofthenexthopdeviceonthewaytothesender.Itis

changedoneachhop.Networkaddressremainsthesame.

YouareanadministratoroftheEzonexamswitchednetworkandyourgoalis

toreducesomeoftheadministrativeoverheadonyournetwork.Youplanon

achievingthisbyconfiguringanewVLANforeachdepartmentintheEzonexam

network.

However,youneedtosharetheVLANinformationacrossnumerous

switches.Whichofthefollowingwouldallowyouaccomplishthis?

A.STP

B.GVRP

C.SNMP

D.VTP

E.DHCP

F.Noneoftheabove

正確答案：D

D解析：Explanation:

TheVTP(VLANTrunkingProtocol)isaCiscoLayer2messagingprotocolthat

managestheaddition,deletion,andrenamingofVLANsonanetwork-widebasis.

ItallowsforVLANinformationtospanmultipleswitcheswithintheswitch

domain.

IncorrectAnswers:

A.STPisaswitchingprotocolbutitisusedforpreventingnetworkloops.

B.GVARPisanactualprotocolusedinswitchadministration,butitbeyondthe

scopeofwhataCCNAisexpectedtoknow.

C.SNMPisaprotocolusedformanagingandmonitoringnetworks

E.DHCPistheDynamicHostConfigurationProtocol,whichallowsforPC'sto

obtaintheirIPaddressdynamicallyuponbootingupzalongwiththeirDNSand

defaultgatewayinformation.

思科認證考試試題及答案5卷第4卷

TheLANneedsareexpandingattheEzonexamcorporateoffice,whichis

quicklygrowing.YouareinstructedtoenlargetheareacoveredbyasingleLAN

segmentontheEzonexamnetwork.

Whichofthefollowingarelayer1devicesthatyoucanuse?(Chooseallthat

apply.)

A.Aswitch

B.Arouter

C.Anetworkadaptercard

D.Ahub

E.Arepeater

正確答案：DE

解析:Explanation:

Ahubsimplyrepeatstheelectricalsignalandmakesnoattempttointerpretthe

electricalsignal(layer1)asaLANframe.(Layer2).So,ahubactuallyperforms

OSIlayer1functions,repeatinganelectricalsignal,whereasaswitchperforms

OSIlayer2functions,actuallyinterpretingEthernetheaderinformation,

particularlyaddresses,tomakeforwardingdecisions.Hubscanbeusedto

increasethenumberofstationsthatcanbesupportedonaLAN.

Becausetherepeaterdoesnotinterpretwhatthebitsmean,butdoesexamine

andgenerateelectricalsignals,arepeaterisconsideredtooperateatLayer1.

RepeaterscanbeusedtophysicallyextendtheLANtogreaterdistances.

YouareaseniornetworkadministratoratEzonexam,andwhileperforming

thepasswordrecoveryprocedureonyour2500seriesCiscorouter,youtypein

thefollowingcommand:

o/r0x2142

Whatisthepurposeofthiscommand?

A.Itisusedtorestarttherouter.

B.ItisusedtobypasstheconfigurationinNVRAM.

C.ItisusedtoenterROMMonitormode.

D.Itisusedtoviewthelostpassword.

E.Itisusedtosavethechangestotheconfiguration.

正確答案：B

解析:Explanation:

Theo/r0x2142commandchangesthevalueofconfig-registerto2142inaCisco

2500seriesrouter,sothattheRouterignorestheNVRAMcontentsandrevertsto

theinitialsetupconfigurationmodewhenitboots.

Whyisfull-duplexEthernetsuperiortoitssingle-duplexcounterpart?(Select

twoanswerchoices.)

A.Itusesinexpensivehubs

B.Itoperateswithoutcollisions

C.Itoperatesonswitches

D.Itprovidesfasterdatatransfer

E.Itutilizesfewerwiringpairs

正確答案：BD

解析：Explanation:

FullduplexEthernetallowsconcurrentsendingandreceiving,whichallowsthe

fullbandwidthtobeusedforbothsendingandreceiving.Theresultisacollision

freenetworkwithincreasedthroughput.

IncorrectAnswers:

A,C.Theseareincorrectbecausefullduplexdoesn'trequirehubsorswitches.Full

duplexoperationcanbeusedonswitchandrouterports,aswellasPChosts.

E.Thisisincorrectbecausefullduplexactuallyusesmorewiringpairs.Infull

duplex,bothwirepairsareused.Halfduplexusesonlyasinglepair.

要在交換機上運行802.1W,可使用哪個命令來啟用該協(xié)議?()

A.Switch(config)#spanning-treemoderapid-pvst

B.Switch#spanning-treemoderapid-pvst

C.Switch(config)#spanning-treemode802.lw

D.Switch#spanning-treemode802.1w

答案：A

屬于私有IP段的是()

A.-55

B.-55

C.-55

D.-55

E.-55

正確答案：ABD

思科認證考試試題及答案5卷第5卷

在大型網(wǎng)絡中選擇OSPF而不選擇RIP的原因是()

A.更快的路由收斂

B.需要更少的路由器內(nèi)存

C.需要更少的CPU的資源

D.更優(yōu)的選路，路由無環(huán)路

正確答案：AD

下面哪一項正確描述了路由協(xié)議()

A.允許數(shù)據(jù)包在主機間傳送的一種協(xié)議

B.定義數(shù)據(jù)包中的格式和用法的一種方式

C.通過執(zhí)行一個算法來完成路由選擇的一種協(xié)議

D指定MAC地址和IP地址捆綁的方式和時間的一種協(xié)議

正確答案：C

YouaregivenaPC,arouter,andacable.Selectthecorrectcombinationthat

willallowyoutologintorouterVE1locallyusingaterminalemulationprogram

suchasHyperTerminal.

A.ConnectthePC'sCOMporttotherouter'sconsoleportusingastraight-

throughcable.

B.ConnectthePC'sCOMporttotherouter'sconsoleportusingarollover

cable.

C.ConnectthePC'sCOMporttotherouter'sEthernetportusingastraight-

throughcable.

D.ConnectthePC'sEthernetporttotherouter'sEthernetportusinga

rollovercable.

E.ConnectthePC'sEthernetporttotherouter'sEthernetportusinga

straight-throughcable.

F.Noneoftheabove

正確答案：B

B解析：Explanation:

ToconnecttheRouterinConsoleporttoconfigureusingHyperTerminal,you

requiredtheRolloverCable,whichconnectsthePC'sCOMporttotherouter's

Consoleport.

IncorrectAnswers:

A,C,E:StraightCablesareusedfor:Hosttoswitch,SwitchtoRouter.

D:RollovercablesareusedforConsole/COMconnections,notforIPtrafficover

the

Ethernetports.

WhatisthemaximumnumberofIPaddressesthatcanbeassignedtohosts

onaEzonexamsubnetthatusesthe24subnetmask?

A