_Here to Help You__ Computer Networks_ Interview

05/12/2014 "HereToHelpYou":ComputerNetworks:Interview

http://dharanyadevi.blogspot.in/search/label/Computer%20Networks%3A%20Interview 1/22

Home Technical Studies Online Gov Portals Salutary Links Interview Questions Question Bank Notes & for UG and PG Soft Skills

Aptitude Video Project Lab Manuals Basics and Viva E-Books Research Softwares UGC More Jobs IEEE & Elsevier Papers

Contact Us

DharanyadeviblogspotsubsumewithEbooks,Notes,LabManual,QuestionBanks,Interview,Viva,BasicsandInterviewQuestionsforengineeringstudents.ForAnyHelpContactusdharanyadeviblogspot@gmail.com

Search

SEARCH

Monday, May 28, 2012

ComputerNetworks:Interview,VivaandBasicQuestionsPart3

Interview,VivaandBasicsQuestionofComputerNetworksPart3

1.DefineNetwork?

Anetworkisasetofdevicesconnectedbyphysicalmedialinks.Anetworkisrecursivelyisaconnectionoftwoormorenodesbyaphysicallinkortwoormorenetworksconnectedbyoneormorenodes.

2.WhatisaLink?

Atthelowestlevel,anetworkcanconsistoftwoormorecomputersdirectlyconnectedbysomephysicalmediumsuchascoaxialcableoropticalfiber.SuchaphysicalmediumiscalledasLink.

3.Whatisanode?

Anetworkcanconsistoftwoormorecomputersdirectlyconnectedbysomephysicalmediumsuchascoaxialcableoropticalfiber.SuchaphysicalmediumiscalledasLinksandthecomputeritconnectsiscalledasNodes.

4.WhatisagatewayorRouter?

AnodethatisconnectedtotwoormorenetworksiscommonlycalledasrouterorGateway.Itgenerallyforwardsmessagefromonenetworktoanother.

5.Whatispointpointlink?

Ifthephysicallinksarelimitedtoapairofnodesitissaidtobepointpointlink.

6.WhatisMultipleAccess?

Ifthephysicallinksaresharedbymorethantwonodes,itissaid

133peoplelikethis.Like Share

DharanyaVillupuram,Hindu,India

WorkingasalecturerinAnnaUniversity,Villupuram!!!http://annauniv.academia.edu/Dharanyadevi

Viewmycompleteprofile

About Me

Is This Website IsInformative????

JointhissitewithGoogleFriendConnect

Members

Alreadyamember?

Follow Us :)!!!

(SS)SystemSoftwareVivaQuestionandAnswers.NetAssemblyInterviewQuestionandAnswerPart9.NetDeploymentInterviewQuestionandAnswerPart4

ShowingpostswithlabelComputerNetworks:Interview. Showallposts



tobeMultipleAccess.

7.WhataretheadvantagesofDistributedProcessing?

a.Security/Encapsulationb.Distributeddatabasec.FasterProblemsolvingd.Securitythroughredundancye.CollaborativeProcessing

8.Whatarethecriterianecessaryforaneffectiveandefficientnetwork?

a.PerformanceItcanbemeasuredinmanyways,includingtransmittimeandresponsetime.b.ReliabilityItismeasuredbyfrequencyoffailure,thetimeittakesalinktorecoverfromafailure,andthenetwork'srobustness.c.SecuritySecurityissuesincludesprotectingdatafromunauthorizedaccessandvirues.

9.Namethefactorsthataffecttheperformanceofthenetwork?

a.NumberofUsersb.Typeoftransmissionmediumc.Hardwared.Software

10.Namethefactorsthataffectthereliabilityofthenetwork?

a.Frequencyoffailureb.Recoverytimeofanetworkafterafailure

11.Namethefactorsthataffectthesecurityofthenetwork?

a.UnauthorizedAccessb.Viruses

12.WhatisProtocol?

Aprotocolisasetofrulesthatgovernallaspectsofinformationcommunication.

13.Whatarethekeyelementsofprotocols?

Thekeyelementsofprotocolsarea.SyntaxItreferstothestructureorformatofthedata,thatistheorderinwhichtheyarepresented.b.SemanticsItreferstothemeaningofeachsectionofbits.c.TimingTimingreferstotwocharacteristics:Whendatashouldbesentandhowfasttheycanbesent.

14.WhatarethekeydesignissuesofacomputerNetwork?

a.Connectivityb.CosteffectiveResourceSharingc.SupportforcommonServicesd.Performance

15.DefineBandwidthandLatency?

NetworkperformanceismeasuredinBandwidth(throughput)andLatency(Delay).Bandwidthofanetworkisgivenbythenumberofbitsthatcanbetransmittedoverthenetworkinacertainperiodoftime.Latencycorrespondstohowlongitt5akesamessagetotravelfromoneendoffanetworktotheother.Itisstrictlymeasuredintermsoftime.

16.DefineRouting?

Theprocessofdeterminingsystematicallyhoetoforwardmessagestowardthedestinationnodesbasedonitsaddressiscalledrouting.

17.Whatisapeerpeerprocess?

Theprocessesoneachmachinethatcommunicateatagivenlayerare

Yes

No

NeedToImprove

Satisfactory

Youmayselectmultipleanswers.

Vote Showresults

Votessofar:203Dayslefttovote:2503

Follow by Email

Emailaddress... Submit

357,074Total Pageviews

funnyquotes

Somepeoplepayacomplimentasiftheyexpectedareceipt.

KinHubbard

Cheeky Quotes

.NetInterviewQuestionandAnswerPart2.NetInterviewQuestionandAnswerPart3.NetInterviewQuestionandAnswerPart6.NetInterviewQuestionandAnswerPart7.NetInterviewQuestionandAnswerPart8.NetInterviewQuestionPart1.NetInterviewQuestionPart5BasicsofCBasicsofWirelessNetworkingC#InterviewQuestionandAnswer(1)CInterviewCInterviewQuestionandAnswerPart1(1)CInterviewQuestionandAnswerPart2(1)CInterviewQuestionandAnswerPart3(1)CInterviewQuestionandAnswerPart4(1)CInterviewQuestionandAnswerPart6(1)CInterviewQuestionsandAnswersPart5CProgramtoCounttheLinesCCNAInterViewQuestionandAnswersCOA2Marks(UnitWise)COAQuestionBank16MarksCognizantTestPatternComputerGraphicsLabManualComputerNetworkLabManualComputerNetwork2MarksComputerNetworks16MarksKeyPointsComputerNetworks:BasicsComputerNetworks:InterviewCS1203SYSTEMSOFTWAREB.E/B.TechDEGREEEXAMINATIONMay/Jun2007CS1302BankCS1304SystemSoftwareQuestionBankCS1312ObjectOrientedProgrammingForEEECS2201DataStructuresQuestionBankCS2401ComputerGraphicsCTSaptitude.DBMSLabManualDeleteAdministratorPasswordDifferenceBetweenLANEC2303ComputerArchitectureandOrganizationQuestionBankEc2303ComputerArchitectureAndOrganizationSyllabusEC2305TransmissionLinesAndWaveGuides2and16MarksQuestionBankEC2401WirelessCommunication2MarksQuestionBankECEEC1008HighSpeedNetworksNov/Dec2009paperEngineeringEconomicsAndFinancialAccountingMG24522MarksEngineeringEconomicsandFinancialManagementMG245216MarksQuestionBankFileCopyPrograminCFileManagementinCFileOperationFunctioninC



calledpeerpeerprocess.

18.Whenaswitchissaidtobecongested?

Itispossiblethataswitchreceivespacketsfasterthanthesharedlinkcanaccommodateandstoresinitsmemory,foranextendedperiodoftime,thentheswitchwilleventuallyrunoutofbufferspace,andsomepacketswillhavetobedroppedandinthisstateissaidtocongestedstate.

19.Whatissemanticgap?

Definingausefulchannelinvolvesbothunderstandingtheapplicationsrequirementsandrecognizingthelimitationsoftheunderlyingtechnology.Thegapbetweenwhatapplicationsexpectsandwhattheunderlyingtechnologycanprovideiscalledsemanticgap.

20.WhatisRoundTripTime?

Thedurationoftimeittakestosendamessagefromoneendofanetworktotheotherandback,iscalledRTT.

21.DefinethetermsUnicasting,MulticcastingandBroadcasting?

Ifthemessageissentfromasourcetoasingledestinationnode,itiscalledUnicasting.Ifthemessageissenttosomesubsetofothernodes,itiscalledMulticasting.IfthemessageissenttoallthemnodesinthenetworkitiscalledBroadcasting.

22.WhatisMultiplexing?

Multiplexingisthesetoftechniquesthatallowsthesimultaneoustransmissionofmultiplesignalsacrossasingledatalink.

23.NamethecategoriesofMultiplexing?

a.FrequencyDivisionMultiplexing(FDM)b.TimeDivisionMultiplexing(TDM)i.SynchronousTDMii.ASynchronousTDMOrStatisticalTDM.c.WaveDivisionMultiplexing(WDM)

24.WhatisFDM?

FDMisananalogtechniquethatcanbeappliedwhenthebandwidthofalinkisgreaterthanthecombinedbandwidthsofthesignalstobetransmitted.

25.WhatisWDM?

WDMisconceptuallythesameasFDM,exceptthatthemultiplexinganddemultiplexinginvolvelightsignalstransmittedthroughfiberopticschannel.

26.WhatisTDM?

TDMisadigitalprocessthatcanbeappliedwhenthedataratecapacityofthetransmissionmediumisgreaterthanthedataraterequiredbythesendingandreceivingdevices.

27.WhatisSynchronousTDM?

InSTDM,themultiplexerallocatesexactlythesametimeslottoeachdeviceatalltimes,whetherornotadevicehasanythingtotransmit.

28.ListthelayersofOSI

a.PhysicalLayerb.DataLinkLayerc.NetworkLayerd.TransportLayere.SessionLayerf.PresentationLayerg.ApplicationLayer

29.Whichlayersarenetworksupportlayers?

a.PhysicalLayer

FilePrograminCFirstYearBasicCProgramPart1FirstYearBasicCProgramPart2FirstYearBasicCProgramPart3FreeDownloadInternetDownloadManagerFreeDownloadUSBDiskSecurity5.4.0.6FullVersionWithUsernameAndSerialKeyGraphicsprograminFedoraGraphics.hinFedora.Graphics.hinLINUXHighSpeedNetworksEC1008:QuestionBankHighSpeedNetworksSyllabusHowtoCreateFolder"CON"HowtoinstallWindows7FromaUSBflashDriveInstallingWindowsMovieMaker6.0onWindows7or8InterviewInterviewandVivaQuestionandAnswerPart2InterviewandVivaQuestionandAnswersPart1InterviewQuestions:OracleIT2401JavaProgramming2MarksJavaProgrammingLabPart1JavaProgrammingLabPart2JavaProgrammingLabPart3JavaRevisionNotesJAVAThreadingInterviewQuestionAndAnswerKernelLabManual:OperatingSystemLatestHighPerformanceProcessorInteli7ProcessorLinearSearchinCandLinearSearchUsingFunctionsLinuxVsUNIXMANandWANMicroprocessorandMicrocontroller2MarksNetworkProtocolInterviewQuestionandAnswersNetworkingInterviewQuestionandAnswerNumberofLinesfromaTextFileandDisplaytheResultOnlineFileSharingWebsitesOOPSLABforCSEAndITOOPSLabManualForEEEOOPSQuestionBankForITOperatingSystem:InterviewOperatingSystem:InterviewOracleJavaCertificationP2PFileSharingSoftwaresPalindromeinCWithoutusingStringFunctionQuestionBankRadioFrequencyIdentification(RFID)(1)Recover(Ctrl+Alt+Del)PermanentlyDeletedFilesSecondYearQuestionBank:DatabaseManagementSystem(DBMS)SecondYearQuestionBank:SoftwareEngineeringandQualityAssuranceServiceOrientedArchitectureShellScripttoFindWhetheranInputNumberisPalindromeorNotShutdownProgramforUbuntuLinux



b.DatalinkLayerandc.NetworkLayers

30.Whichlayersareusersupportlayers?

a.SessionLayerb.PresentationLayerandc.ApplicationLayer

31.Whichlayerlinksthenetworksupportlayersandusersupportlayers?

TheTransportlayerlinksthenetworksupportlayersandusersupportlayers.

32.WhataretheconcernsofthePhysicalLayer?

Physicallayercoordinatesthefunctionsrequiredtotransmitabitstreamoveraphysicalmedium.a.Physicalcharacteristicsofinterfacesandmediab.Representationofbitsc.Datarated.Synchronizationofbitse.Lineconfigurationf.Physicaltopologyg.Transmissionmode

33.WhataretheresponsibilitiesofDataLinkLayer?

TheDataLinkLayertransformsthephysicallayer,arawtransmissionfacility,toareliablelinkandisresponsiblefornodenodedelivery.a.Framingb.PhysicalAddressingc.FlowControld.ErrorControle.AccessControl

34.WhataretheresponsibilitiesofNetworkLayer?

TheNetworkLayerisresponsibleforthesourcetodestinationdeliveryofpacketpossiblyacrossmultiplenetworks(links).a.LogicalAddressingb.Routing

35.WhataretheresponsibilitiesofTransportLayer?

TheTransportLayerisresponsibleforsourcetodestinationdeliveryoftheentiremessage.a.ServicepointAddressingb.Segmentationandreassemblyc.ConnectionControld.FlowControle.ErrorControl

36.WhataretheresponsibilitiesofSessionLayer?

TheSessionlayeristhenetworkdialogController.Itestablishes,maintainsandsynchronizestheinteractionbetweenthecommunicatingsystems.a.Dialogcontrolb.Synchronization

37.WhataretheresponsibilitiesofPresentationLayer?

ThePresentationlayerisconcernedwiththesyntaxandsemanticsoftheinformationexchangedbetweentwosystems.a.Translationb.Encryptionc.Compression

38.WhataretheresponsibilitiesofApplicationLayer?

TheApplicationLayerenablestheuser,whetherhumanorsoftware,toaccessthenetwork.Itprovidesuserinterfacesandsupportforservicessuchasemail,shareddatabasemanagementandothertypesofdistributedinformationservices.a.NetworkvirtualTerminalb.Filetransfer,accessandManagement(FTAM)

inCSOALABSystemSoftwareLabThirdYearQuestionBank:CryptographyandNetworkSercurity(1)ThirdYearQuestionBank:NetworkProgrammingandManagementUseYourPendriveAsRAMVivaandBasicQuestionandAnswerofOperatingSystemPart1VivaandBasicQuestionandAnswerPart4VivaandBasicQuestionandAnswerPart5VivaandBasicQuestionsofDataStructurePart2VivaandBasicQuestionsofDataStructuresVivaandBasicQuestionsofDBMS(1)VivaandBasicQuestionsofJAVAPart1VivaandBasicQuestionsofJavaPart2(1)VivaandBasicQuestionsofOOPSPart1VivaandBasicQuestionsPart1VivaandBasicQuestionsPart3VivaandBasicQuestionsPart4VivaandBasicQuestionsPart6VivaandBasicsofOperatingSystemPart2WebDevelopmentToolsWebTechnologyLabManualWhatisSystemSoftware???????WindowsRunCommandsandShortCutsKeysWirelessCommunication16MarksQuestionBankWordsandCharactersinaGivenTextWriteaCProgramtoCounttheNumberofCharacterXMLInterviewQuestionandAnswer(1)

http://www.flipkart.com



c.Mailservicesd.DirectoryServices

39.Whatarethetwoclassesofhardwarebuildingblocks?

NodesandLinks.

40.Whatarethedifferentlinktypesusedtobuildacomputernetwork?

a.Cablesb.LeasedLinesc.LastMileLinksd.WirelessLinks

41.WhatarethecategoriesofTransmissionmedia?

a.GuidedMediai.TwistedPaircable1.ShieldedTP2.UnshieldedTPii.CoaxialCableiii.Fiberopticcableb.UnguidedMediai.Terrestrialmicrowaveii.SatelliteCommunication

42.Whatarethetypesoferrors?

a.SingleBiterrorInasinglebiterror,onlyonebitinthedataunithaschangedb.BurstErrorABursterrormeansthattwoormorebitsinthedatahavechanged.

43.WhatisErrorDetection?Whatareitsmethods?

Datacanbecorruptedduringtransmission.ForreliablecommunicationerrorsmustbedeductedandCorrected.ErrorDetectionusestheconceptofredundancy,whichmeansaddingextrabitsfordetectingerrorsatthedestination.ThecommonErrorDetectionmethodsarea.VerticalRedundancyCheck(VRC)b.LongitudinalRedundancyCheck(VRC)c.CyclicRedundancyCheck(VRC)d.Checksum

44.WhatisRedundancy?

Theconceptofincludingextrainformationinthetransmissionsolelyforthepurposeofcomparison.Thistechniqueiscalledredundancy.

45.WhatisVRC?

ItisthemostcommonandleastexpensivemechanismforErrorDetection.InVRC,aparitybitisaddedtoeverydataunitsothatthetotalnumberof1sbecomesevenforevenparity.Itcandetectallsinglebiterrors.Itcandetectbursterrorsonlyifthetotalnumberoferrorsineachdataunitisodd.

46.WhatisLRC?

InLRC,ablockofbitsisdividedintorowsandaredundantrowofbitsisaddedtothewholeblock.Itcandetectbursterrors.Iftwobitsinonedataunitaredamagedandbitsinexactlythesamepositionsinanotherdataunitarealsodamaged,theLRCcheckerwillnotdetectanerror.InLRCaredundantdataunitfollowsndataunits.

47.WhatisCRC?

CRC,isthemostpowerfuloftheredundancycheckingtechniques,isbasedonbinarydivision.

48.WhatisChecksum?

Checksumisusedbythehigherlayerprotocols(TCP/IP)forerrordetection

49.Listthestepsinvolvedincreatingthechecksum.



a.Dividethedataintosectionsb.Addthesectionstogetherusing1'scomplementarithmeticc.Takethecomplementofthefinalsum,thisisthechecksum.

50.WhataretheDatalinkprotocols?

Datalinkprotocolsaresetsofspecificationsusedtoimplementthedatalinklayer.ThecategoriesofDataLinkprotocolsare1.AsynchronousProtocols2.SynchronousProtocolsa.CharacterOrientedProtocolsb.BitOrientedprotocols

51.CompareErrorDetectionandErrorCorrection:

Thecorrectionoferrorsismoredifficultthanthedetection.Inerrordetection,checksonlyanyerrorhasoccurred.Inerrorcorrection,theexactnumberofbitsthatarecorruptedandlocationinthemessageareknown.Thenumberoftheerrorsandthesizeofthemessageareimportantfactors.

52.WhatisForwardErrorCorrection?

Forwarderrorcorrectionistheprocessinwhichthereceivertriestoguessthemessagebyusingredundantbits.

53.DefineRetransmission?

Retransmissionisatechniqueinwhichthereceiverdetectstheoccurrenceofanerrorandasksthesendertoresendthemessage.Resendingisrepeateduntilamessagearrivesthatthereceiverbelievesiserrorfreed.

54.WhatareDataWords?

Inblockcoding,wedivideourmessageintoblocks,eachofkbits,calleddatawords.Theblockcodingprocessisonetoone.Thesamedatawordisalwaysencodedasthesamecodeword.

55.WhatareCodeWords?

"r"redundantbitsareaddedtoeachblocktomakethelengthn=k

+r.Theresultingnbitblocksarecalledcodewords.2n2k

codewordsthatarenotused.Thesecodewordsareinvalidorillegal.

56.WhatisaLinearBlockCode?

AlinearblockcodeisacodeinwhichtheexclusiveOR(additionmodulo2)oftwovalidcodewordscreatesanothervalidcodeword.

57.WhatareCyclicCodes?

Cycliccodesarespeciallinearblockcodeswithoneextraproperty.Inacycliccode,ifacodewordiscyclicallyshifted(rotated),theresultisanothercodeword.

58.DefineEncoder?

Adeviceorprogramthatusespredefinedalgorithmstoencode,orcompressaudioorvideodataforstorageortransmissionuse.Acircuitthatisusedtoconvertbetweendigitalvideoandanalogvideo.

59.DefineDecoder?

Adeviceorprogramthattranslatesencodeddataintoitsoriginalformat(e.g.itdecodesthedata).ThetermisoftenusedinreferencetoMPEG2videoandsounddata,whichmustbedecodedbeforeitisoutput.

60.WhatisFraming?

Framinginthedatalinklayerseparatesamessagefromonesourcetoadestination,orfromothermessagestootherdestinations,byaddingasenderaddressandadestinationaddress.Thedestinationaddressdefineswherethepackethastogoandthesenderaddresshelpstherecipientacknowledgethereceipt.

61.WhatisFixedSizeFraming?



Infixedsizeframing,thereisnoneedfordefiningtheboundariesoftheframes.Thesizeitselfcanbeusedasadelimiter.

62.DefineCharacterStuffing?

Inbytestuffing(orcharacterstuffing),aspecialbyteisaddedtothedatasectionoftheframewhenthereisacharacterwiththesamepatternastheflag.Thedatasectionisstuffedwithanextrabyte.Thisbyteisusuallycalledtheescapecharacter(ESC),whichhasapredefinedbitpattern.WheneverthereceiverencounterstheESCcharacter,itremovesitfromthedatasectionandtreatsthenextcharacterasdata,notadelimitingflag.

63.WhatisBitStuffing?

Bitstuffingistheprocessofaddingoneextra0wheneverfiveconsecutiveIsfollowa0inthedata,sothatthereceiverdoesnotmistakethepattern0111110foraflag.

64.WhatisFlowControl?

Flowcontrolreferstoasetofproceduresusedtorestricttheamountofdatathatthesendercansendbeforewaitingforacknowledgment.

65.WhatisErrorControl?

Errorcontrolisbotherrordetectionanderrorcorrection.Itallowsthereceivertoinformthesenderofanyframeslostordamagedintransmissionandcoordinatestheretransmissionofthoseframesbythesender.Inthedatalinklayer,thetermerrorcontrolrefersprimarilytomethodsoferrordetectionandretransmission.

66.WhatAutomaticRepeatRequest(ARQ)?

Errorcontrolisbotherrordetectionanderrorcorrection.Itallowsthereceivertoinformthesenderofanyframeslostordamagedintransmissionandcoordinatestheretransmissionofthoseframesbythesender.Inthedatalinklayer,thetermerrorcontrolrefersprimarilytomethodsoferrordetectionandretransmission.Errorcontrolinthedatalinklayerisoftenimplementedsimply:Anytimeanerrorisdetectedinanexchange,specifiedframesareretransmitted.Thisprocessiscalledautomaticrepeatrequest(ARQ).

67.WhatisStopandWaitProtocol?

InStopandwaitprotocol,sendersendsoneframe,waitsuntilitreceivesconfirmationfromthereceiver(okaytogoahead),andthensendsthenextframe.

68.WhatisStopandWaitAutomaticRepeatRequest?

ErrorcorrectioninStopandWaitARQisdonebykeepingacopyofthesentframeandretransmittingoftheframewhenthetimerexpires.

69.WhatisusageofSequenceNumberinRelaibleTransmission?

Theprotocolspecifiesthatframesneedtobenumbered.Thisisdonebyusingsequencenumbers.Afieldisaddedtothedataframetoholdthesequencenumberofthatframe.Sincewewanttominimizetheframesize,thesmallestrangethatprovidesunambiguouscommunication.Thesequencenumberscanwraparound.

70.WhatisPipelining?

Innetworkingandinotherareas,ataskisoftenbegunbeforetheprevioustaskhasended.Thisisknownaspipelining.

71.WhatisSlidingWindow?

Theslidingwindowisanabstractconceptthatdefinestherangeofsequencenumbersthatistheconcernofthesenderandreceiver.Inotherwords,hesenderandreceiverneedtodealwithonlypartofthepossiblesequencenumbers.

72.WhatisPiggyBacking?

Atechniquecalledpiggybackingisusedtoimprovetheefficiencyof



thebidirectionalprotocols.WhenaframeiscarryingdatafromAtoB,itcanalsocarrycontrolinformationaboutarrived(orlost)framesfromBwhenaframeiscarryingdatafromBtoA,itcanalsocarrycontrolinformationaboutthearrived(orlost)framesfromA.

Whatarethetwotypesoftransmissiontechnologyavailable?

(i)Broadcastand(ii)pointtopoint

74.Whatissubnet?

Agenerictermforsectionofalargenetworksusuallyseparatedbyabridgeorrouter.

75.Differencebetweenthecommunicationandtransmission.

Transmissionisaphysicalmovementofinformationandconcernissueslikebitpolarity,synchronisation,clocketc.

Communicationmeansthemeaningfullexchangeofinformationbetweentwocommunicationmedia.

76.Whatarethepossiblewaysofdataexchange?

(i)Simplex(ii)Halfduplex(iii)Fullduplex.

77.WhatisSAP?

Seriesofinterfacepointsthatallowothercomputerstocommunicatewiththeotherlayersofnetworkprotocolstack.

78.Whatdoyoumeantby"tripleX"inNetworks?

ThefunctionofPAD(PacketAssemblerDisassembler)isdescribedinadocumentknownasX.3.ThestandardprotocolhasbeendefinedbetweentheterminalandthePAD,calledX.28anotherstandardprotocolexistsbetweenhtePADandthenetwork,calledX.29.Together,thesethreerecommendationsareoftencalled"tripleX".

79.Whatisframerelay,inwhichlayeritcomes?

Framerelayisapacketswitchingtechnology.Itwilloperateinthedatalinklayer.

80.Whatisterminalemulation,inwhichlayeritcomes?

Telnetisalsocalledasterminalemulation.Itbelongstoapplicationlayer.

81.WhatisBeaconing?

Theprocessthatallowsanetworktoselfrepairnetworksproblems.Thestationsonthenetworknotifytheotherstationsontheringwhentheyarenotreceivingthetransmissions.BeaconingisusedinTokenringandFDDInetworks.

82.Whatisredirector?

RedirectorissoftwarethatinterceptsfileorprintsI/Orequestsandtranslatesthemintonetworkrequests.Thiscomesunderpresentationlayer.

83.WhatisNETBIOSandNETBEUI?

NETBIOSisaprogramminginterfacethatallowsI/Orequeststobesenttoandreceivedfromaremotecomputerandithidesthenetworkinghardwarefromapplications.

NETBEUIisNetBIOSextendeduserinterface.AtransportprotocoldesignedbymicrosoftandIBMfortheuseonsmallsubnets.

84.WhatisRAID?

Amethodforprovidingfaulttolerancebyusingmultipleharddiskdrives.

85.Whatispassivetopology?

Whenthecomputersonthenetworksimplylistenandreceivethesignal,theyarereferredtoaspassivebecausetheydon'tamplifythesignalinanyway.Exampleforpassivetopologylinearbus.



86.WhatisBrouter?

Hybriddevicesthatcombinethefeaturesofbothbridgesandrouters.

87.Whatiscladding?

Alayerofaglasssurroundingthecenterfiberofglassinsideafiberopticcable.

88.Whatispointtopointprotocol?

AcommunicationsprotocolusedtoconnectcomputerstoremotenetworkingservicesincludingInternetserviceproviders.

89.HowGatewayisdifferentfromRouters?

AgatewayoperatesattheupperlevelsoftheOSImodelandtranslatesinformationbetweentwocompletelydifferentnetworkarchitecturesordataformats.

90.Whatisattenuation?

Thedegenerationofasignaloverdistanceonanetworkcableiscalledattenuation.

91.WhatisMACaddress?

TheaddressforadeviceasitisidentifiedattheMediaAccessControl(MAC)layerinthenetworkarchitecture.MACaddressisusuallystoredinROMonthenetworkadaptercardandisunique.

92.Differencebetweenbitrateandbaudrate.

Bitrateisthenumberofbitstransmittedduringonesecondwhereasbaudratereferstothenumberofsignalunitspersecondthatarerequiredtorepresentthosebits.baudrate=(bitrate/N)whereNisnoofbitsrepresentedbyeachsignalshift.

93.WhatisBandwidth?

Everylinehasanupperlimitandalowerlimitonthefrequencyofsignalsitcancarry.Thislimitedrangeiscalledthebandwidth.

94.WhatarethetypesofTransmissionmedia?

Signalsareusuallytransmittedoversometransmissionmediathatarebroadlyclassifiedintotwocategories.

a.)GuidedMedia:Thesearethosethatprovideaconduitfromonedevicetoanotherthatincludetwistedpair,coaxialcableandfiberopticcable.Asignaltravelingalonganyofthesemediaisdirectedandiscontainedbythephysicallimitsofthemedium.Twistedpairandcoaxialcableusemetallicthatacceptandtransportsignalsintheformofelectricalcurrent.Opticalfiberisaglassorplasticcablethatacceptsandtransportssignalsintheformoflight.

b.)UnguidedMedia:Thisisthewirelessmediathattransportelectromagneticwaveswithoutusingaphysicalconductor.Signalsarebroadcasteitherthroughair.Thisisdonethroughradiocommunication,satellitecommunicationandcellulartelephony.

95.WhatisProject802?

ItisaprojectstartedbyIEEEtosetstandardstoenableintercommunicationbetweenequipmentfromavarietyofmanufacturers.Itisawayforspecifyingfunctionsofthephysicallayer,thedatalinklayerandtosomeextentthenetworklayertoallowforinterconnectivityofmajorLANprotocols.

Itconsistsofthefollowing:1. 802.1isaninternetworkingstandardforcompatibilityof

differentLANsandMANsacrossprotocols.2. 802.2Logicallinkcontrol(LLC)istheuppersublayerof

thedatalinklayerwhichisnonarchitecturespecific,thatisremainsthesameforallIEEEdefinedLANs.

3. Mediaaccesscontrol(MAC)isthelowersublayerofthedatalinklayerthatcontainssomedistinctmoduleseachcarryingproprietaryinformationspecifictotheLANproductbeingused.ThemodulesareEthernetLAN(802.3),TokenringLAN(802.4),TokenbusLAN(802.5).



4. 802.6isdistributedqueuedualbus(DQDB)designedtobeusedinMANs.

96.WhatisProtocolDataUnit?

ThedataunitintheLLCleveliscalledtheprotocoldataunit(PDU).ThePDUcontainsoffourfieldsadestinationserviceaccesspoint(DSAP),asourceserviceaccesspoint(SSAP),acontrolfieldandaninformationfield.DSAP,SSAPareaddressesusedbytheLLCtoidentifytheprotocolstacksonthereceivingandsendingmachinesthataregeneratingandusingthedata.ThecontrolfieldspecifieswhetherthePDUframeisainformationframe(Iframe)orasupervisoryframe(Sframe)oraunnumberedframe(Uframe).

97.Whatarethedifferenttypeofnetworking/internetworkingdevices?

1. Repeater:Alsocalledaregenerator,itisanelectronicdevicethatoperatesonlyatphysicallayer.Itreceivesthesignalinthenetworkbeforeitbecomesweak,regeneratestheoriginalbitpatternandputstherefreshedcopybackintothelink.

2. Bridges:TheseoperatebothinthephysicalanddatalinklayersofLANsofsametype.Theydividealargernetworkintosmallersegments.Theycontainlogicthatallowthemtokeepthetrafficforeachsegmentseparateandthusarerepeatersthatrelayaframeonlythesideofthesegmentcontainingtheintendedrecipentandcontrolcongestion.

3. Routers:Theyrelaypacketsamongmultipleinterconnectednetworks(i.e.LANsofdifferenttype).Theyoperateinthephysical,datalinkandnetworklayers.Theycontainsoftwarethatenablethemtodeterminewhichoftheseveralpossiblepathsisthebestforaparticulartransmission.

4. Gateways:Theyrelaypacketsamongnetworksthathavedifferentprotocols(e.g.betweenaLANandaWAN).Theyacceptapacketformattedforoneprotocolandconvertittoapacketformattedforanotherprotocolbeforeforwardingit.TheyoperateinallsevenlayersoftheOSImodel.

98.WhatisICMP?

ICMPisInternetControlMessageProtocol,anetworklayerprotocoloftheTCP/IPsuiteusedbyhostsandgatewaystosendnotificationofdatagramproblemsbacktothesender.Itusestheechotest/replytotestwhetheradestinationisreachableandresponding.Italsohandlesbothcontrolanderrormessages.

99.WhatarethedataunitsatdifferentlayersoftheTCP/IPprotocolsuite?

Thedataunitcreatedattheapplicationlayeriscalledamessage,atthetransportlayerthedataunitcreatediscalledeitherasegmentoranuserdatagram,atthenetworklayerthedataunitcreatediscalledthedatagram,atthedatalinklayerthedatagramisencapsulatedintoaframeandfinallytransmittedassignalsalongthetransmissionmedia.

100.WhatisdifferencebetweenARPandRARP?

Theaddressresolutionprotocol(ARP)isusedtoassociatethe32bitIPaddresswiththe48bitphysicaladdress,usedbyahostoraroutertofindthephysicaladdressofanotherhostonitsnetworkbysendingaARPquerypacketthatincludestheIPaddressofthereceiver.

Thereverseaddressresolutionprotocol(RARP)allowsahosttodiscoveritsInternetaddresswhenitknowsonlyitsphysicaladdress.

101.WhatistheminimumandmaximumlengthoftheheaderintheTCPsegmentandIPdatagram?

Theheadershouldhaveaminimumlengthof20bytesandcanhaveamaximumlengthof60bytes.

102.Whatistherangeofaddressesintheclassesofinternetaddresses?

ClassA0.0.0.0127.255.255.255ClassB128.0.0.0191.255.255.255ClassC192.0.0.0223.255.255.255ClassD224.0.0.0239.255.255.255ClassE240.0.0.0247.255.255.255

103.WhatisthedifferencebetweenTFTPandFTPapplicationlayerprotocols?



TheTrivialFileTransferProtocol(TFTP)allowsalocalhosttoobtainfilesfromaremotehostbutdoesnotprovidereliabilityorsecurity.ItusesthefundamentalpacketdeliveryservicesofferedbyUDP.

TheFileTransferProtocol(FTP)isthestandardmechanismprovidedbyTCP/IPforcopyingafilefromonehosttoanother.ItusestheservicesofferbyTCPandsoisreliableandsecure.Itestablishestwoconnections(virtualcircuits)betweenthehosts,onefordatatransferandanotherforcontrolinformation.

104.Whataremajortypesofnetworksandexplain?

1. Serverbasednetwork:providecentralizedcontrolofnetworkresourcesandrelyonservercomputerstoprovidesecurityandnetworkadministration

2. Peertopeernetwork:computerscanactasbothserverssharingresourcesandasclientsusingtheresources.

105.Whataretheimportanttopologiesfornetworks?

1. BUStopology:Inthiseachcomputerisdirectlyconnectedtoprimarynetworkcableinasingleline.Advantages:Inexpensive,easytoinstall,simpletounderstand,easytoextend.

2. STARtopology:Inthisallcomputersareconnectedusingacentralhub.Advantages:Canbeinexpensive,easytoinstallandreconfigureandeasytotroubleshootphysicalproblems.

3. RINGtopology:Inthisallcomputersareconnectedinloop.Advantages:Allcomputershaveequalaccesstonetworkmedia,installationcanbesimple,andsignaldoesnotdegradeasmuchasinothertopologiesbecauseeachcomputerregeneratesit.

106.Whatismeshnetwork?

Anetworkinwhichtherearemultiplenetworklinksbetweencomputerstoprovidemultiplepathsfordatatotravel.

107.Whatisdifferencebetweenbasebandandbroadbandtransmission?

Inabasebandtransmission,theentirebandwidthofthecableisconsumedbyasinglesignal.Inbroadbandtransmission,signalsaresentonmultiplefrequencies,allowingmultiplesignalstobesentsimultaneously.

108.Explain543rule?

InaEthernetnetwork,betweenanytwopointsonthenetwork,therecanbenomorethanfivenetworksegmentsorfourrepeaters,andofthosefivesegmentsonlythreeofsegmentscanbepopulated.

109.WhatMAU?

IntokenRing,hubiscalledMultistationAccessUnit(MAU).

110.Whatisthedifferencebetweenroutableandnonroutableprotocols?

Routableprotocolscanworkwitharouterandcanbeusedtobuildlargenetworks.NonRoutableprotocolsaredesignedtoworkonsmall,localnetworksandcannotbeusedwitharouter.

111.WhyshouldyoucareabouttheOSIReferenceModel?

Itprovidesaframeworkfordiscussingnetworkoperationsanddesign.

112.Whatislogicallinkcontrol?

OneoftwosublayersofthedatalinklayerofOSIreferencemodel,asdefinedbytheIEEE802standard.Thissublayerisresponsibleformaintainingthelinkbetweencomputerswhentheyaresendingdataacrossthephysicalnetworkconnection.

113.Whatisvirtualchannel?

Virtualchannelisnormallyaconnectionfromonesourcetoonedestination,althoughmulticastconnectionsarealsopermitted.Theothernameforvirtualchannelisvirtualcircuit.

114.Whatisvirtualpath?



Alonganytransmissionpathfromagivensourcetoagivendestination,agroupofvirtualcircuitscanbegroupedtogetherintowhatiscalledpath.

115.Whatispacketfilter?

Packetfilterisastandardrouterequippedwithsomeextrafunctionality.Theextrafunctionalityallowseveryincomingoroutgoingpackettobeinspected.Packetsmeetingsomecriterionareforwardednormally.Thosethatfailthetestaredropped.

116.Whatistrafficshaping?

Oneofthemaincausesofcongestionisthattrafficisoftenbusy.Ifhostscouldbemadetotransmitatauniformrate,congestionwouldbelesscommon.Anotheropenloopmethodtohelpmanagecongestionisforcingthepackettobetransmittedatamorepredictablerate.Thisiscalledtrafficshaping.

117.Whatismulticastrouting?

Sendingamessagetoagroupiscalledmulticasting,anditsroutingalgorithmiscalledmulticastrouting.

118.Whatisregion?

Whenhierarchicalroutingisused,theroutersaredividedintowhatwewillcallregions,witheachrouterknowingallthedetailsabouthowtoroutepacketstodestinationswithinitsownregion,butknowingnothingabouttheinternalstructureofotherregions.

119.Whatissillywindowsyndrome?

ItisaproblemthatcanruinTCPperformance.ThisproblemoccurswhendataarepassedtothesendingTCPentityinlargeblocks,butaninteractiveapplicationonthereceivingsidereads1byteatatime.

120.WhatareDigramsandTrigrams?

Themostcommontwolettercombinationsarecalledasdigrams.e.g.th,in,er,reandan.Themostcommonthreelettercombinationsarecalledastrigrams.e.g.the,ing,and,andion.

121.ExpandIDEA.

IDEAstandsforInternationalDataEncryptionAlgorithm.

122.Whatiswidemouthfrog?

Widemouthfrogisthesimplestknownkeydistributioncenter(KDC)authenticationprotocol.

123.WhatisMailGateway?

Itisasystemthatperformsaprotocoltranslationbetweendifferentelectronicmaildeliveryprotocols.

124.WhatisIGP(InteriorGatewayProtocol)?

Itisanyroutingprotocolusedwithinanautonomoussystem.

125.WhatisEGP(ExteriorGatewayProtocol)?

Itistheprotocoltheroutersinneighboringautonomoussystemsusetoidentifythesetofnetworksthatcanbereachedwithinorviaeachautonomoussystem.

126.Whatisautonomoussystem?

ItisacollectionofroutersunderthecontrolofasingleadministrativeauthorityandthatusesacommonInteriorGatewayProtocol.

127.WhatisBGP(BorderGatewayProtocol)?

Itisaprotocolusedtoadvertisethesetofnetworksthatcanbereachedwithinanautonomoussystem.BGPenablesthisinformationtobesharedwiththeautonomoussystem.ThisisnewerthanEGP(ExteriorGatewayProtocol).



PostedbyDharanyaat11:43PM Nocomments:

Labels:ComputerNetworks:Interview,VivaandBasicQuestionsPart3

128.WhatisGatewaytoGatewayprotocol?

ItisaprotocolformerlyusedtoexchangeroutinginformationbetweenInternetcorerouters.

129.WhatisNVT(NetworkVirtualTerminal)?

Itisasetofrulesdefiningaverysimplevirtualterminalinteraction.TheNVTisusedinthestartofaTelnetsession.

130.WhatisaMultihomedHost?

ItisahostthathasamultiplenetworkinterfacesandthatrequiresmultipleIPaddressesiscalledasaMultihomedHost.

131.WhatisKerberos?

ItisanauthenticationservicedevelopedattheMassachusettsInstituteofTechnology.Kerberosusesencryptiontopreventintrudersfromdiscoveringpasswordsandgainingunauthorizedaccesstofiles.

132.WhatisOSPF?

ItisanInternetroutingprotocolthatscaleswell,canroutetrafficalongmultiplepaths,andusesknowledgeofanInternet'stopologytomakeaccurateroutingdecisions.

133.WhatisProxyARP?

ItisusingaroutertoanswerARPrequests.Thiswillbedonewhentheoriginatinghostbelievesthatadestinationislocal,wheninfactisliesbeyondrouter.

134.WhatisSLIP(SerialLineInterfaceProtocol)?

ItisaverysimpleprotocolusedfortransmissionofIPdatagramsacrossaserialline.

135.WhatisRIP(RoutingInformationProtocol)?

Itisasimpleprotocolusedtoexchangeinformationbetweentherouters.

136.Whatissourceroute?

ItisasequenceofIPaddressesidentifyingtherouteadatagrammustfollow.AsourceroutemayoptionallybeincludedinanIPdatagramheader.

Recommend this on Google

ComputerNetworks:Interview,VivaandBasicQuestionsPart4

Interview,VivaandBasicQuestionsofComputerNetworksPart4

1.Whatare10Base2,10Base5and10BaseTEthernetLANs?10Base2AnEthernettermmeaningamaximumtransferrateof10Megabitspersecondthatusesbasebandsignaling,withacontiguouscablesegmentlengthof100metersandamaximumof2segments.



10Base5AnEthernettermmeaningamaximumtransferrateof10Megabitspersecondthatusesbasebandsignaling,with5continuoussegmentsnotexceeding100meterspersegment.10BaseTAnEthernettermmeaningamaximumtransferrateof10Megabitspersecondthatusesbasebandsignalingandtwistedpaircabling.

2.Whatisthedifferencebetweenanunspecifiedpassiveopenandafullyspecifiedpassiveopen?Anunspecifiedpassiveopenhastheserverwaitingforaconnectionrequestfromaclient.Afullyspecifiedpassiveopenhastheserverwaitingforaconnectionfromaspecificclient.

3.ExplainthefunctionofTransmissionControlBlock?ATCBisacomplexdatastructurethatcontainsaconsiderableamountofinformationabouteachconnection.

4.WhatisaManagementInformationBase(MIB)?AManagementInformationBaseispartofeverySNMPmanageddevice.EachSNMPagenthastheMIBdatabasethatcontainsinformationaboutthedevice'sstatus,itsperformance,connections,andconfiguration.TheMIBisqueriedbySNMP.

5.WhatisanonymousFTPandwhywouldyouuseit?AnonymousFTPenablesuserstoconnecttoahostwithoutusingavalidloginandpassword.Usually,anonymousFTPusesalogincalledanonymousorguest,withthepasswordusuallyrequestingtheuser'sIDfortrackingpurposesonly.AnonymousFTPisusedtoenablealargenumberofuserstoaccessfilesonthehostwithouthavingtogotothetroubleofsettinguploginsforthemall.AnonymousFTPsystemsusuallyhavestrictcontrolsovertheareasananonymoususercanaccess.

6.Whatisapseudotty?ApseudottyorfalseterminalenablesexternalmachinestoconnectthroughTelnetorrlogin.Withoutapseudotty,noconnectioncantakeplace.

7.Whichlayerofthe7layermodelprovidesservicestotheApplicationlayerovertheSessionlayerconnection?Presentation.

8.WhatdoestheMountprotocoldo?TheMountprotocolreturnsafilehandleandthenameofthefilesysteminwhicharequestedfileresides.Themessageissenttotheclientfromtheserverafterreceptionofaclient'srequest.

9.WhatisExternalDataRepresentation?ExternalDataRepresentationisamethodofencodingdatawithinanRPCmessage,usedtoensurethatthedataisnotsystemdependent.

10.WhichOSIReferenceLayercontrolsapplicationtoapplicationcommunication?Session

11.BOOTPhelpsadisklessworkstationboot.HowdoesitgetamessagetothenetworklookingforitsIPaddressandthelocationofitsoperatingsystembootfiles?BOOTPsendsaUDPmessagewithasubnetworkbroadcastaddressandwaitsforareplyfromaserverthatgivesittheIPaddress.Thesamemessagemightcontainthenameofthemachinethathasthebootfilesonit.Ifthebootimagelocationisnotspecified,theworkstationsendsanotherUDPmessagetoquerytheserver.

12.WhatisaDNSresourcerecord?Aresourcerecordisanentryinanameserver'sdatabase.Thereareseveraltypesofresourcerecordsused,includingnametoaddressresolutioninformation.ResourcerecordsaremaintainedasASCIIfiles.

13.WhatprotocolisusedbyDNSnameservers?DNSusesUDPforcommunicationbetweenservers.Itisabetter



choicethanTCPbecauseoftheimprovedspeedaconnectionlessprotocoloffers.Ofcourse,transmissionreliabilitysufferswithUDP.

14.Whatisthedifferencebetweeninteriorandexteriorneighborgateways?InteriorgatewaysconnectLANsofoneorganization,whereasexteriorgatewaysconnecttheorganizationtotheoutsideworld.

15.WhatistheHELLOprotocolusedfor?TheHELLOprotocolusestimeinsteadofdistancetodetermineoptimalrouting.ItisanalternativetotheRoutingInformationProtocol.

16.Whataretheadvantagesanddisadvantagesofthethreetypesofroutingtables?Thethreetypesofroutingtablesarefixed,dynamic,andfixedcentral.Thefixedtablemustbemanuallymodifiedeverytimethereisachange.Adynamictablechangesitsinformationbasedonnetworktraffic,reducingtheamountofmanualmaintenance.Afixedcentraltableletsamanagermodifyonlyonetable,whichisthenreadbyotherdevices.Thefixedcentraltablereducestheneedtoupdateeachmachine'stable,aswiththefixedtable.Usuallyadynamictablecausesthefewestproblemsforanetworkadministrator,althoughthetable'scontentscanchangewithouttheadministratorbeingawareofthechange.

17.WhatisacharacteristicofStoreandForwardswitches?TheyreadtheentireframeandcheckCRCbeforeforwarding.

18.Whatissourceroute?ItisasequenceofIPaddressesidentifyingtherouteadatagrammustfollow.AsourceroutemayoptionallybeincludedinanIPdatagramheader.

19.WhatisRIP(RoutingInformationProtocol)?Itisasimpleprotocolusedtoexchangeinformationbetweentherouters.

20.WhatisSLIP(SerialLineInterfaceProtocol)?ItisaverysimpleprotocolusedfortransmissionofIPdatagramsacrossaserialline.

21.WhatisProxyARP?ItisusingaroutertoanswerARPrequests.Thiswillbedonewhentheoriginatinghostbelievesthatadestinationislocal,wheninfactisliesbeyondrouter.

22.WhatisOSPF?ItisanInternetroutingprotocolthatscaleswell,canroutetrafficalongmultiplepaths,andusesknowledgeofanInternet'stopologytomakeaccurateroutingdecisions.

23.WhatisKerberos?ItisanauthenticationservicedevelopedattheMassachusettsInstituteofTechnology.Kerberosusesencryptiontopreventintrudersfromdiscoveringpasswordsandgainingunauthorizedaccesstofiles.

24.WhatisaMultihomedHost?ItisahostthathasamultiplenetworkinterfacesandthatrequiresmultipleIPaddressesiscalledasaMultihomedHost.

25.WhatisNVT(NetworkVirtualTerminal)?Itisasetofrulesdefiningaverysimplevirtualterminalinteraction.TheNVTisusedinthestartofaTelnetsession.

26.WhatisGatewaytoGatewayprotocol?ItisaprotocolformerlyusedtoexchangeroutinginformationbetweenInternetcorerouters.

27.WhatisBGP(BorderGatewayProtocol)?Itisaprotocolusedtoadvertisethesetofnetworksthatcanbe



reachedwithinanautonomoussystem.BGPenablesthisinformationtobesharedwiththeautonomoussystem.ThisisnewerthanEGP(ExteriorGatewayProtocol).

28.Whatisautonomoussystem?ItisacollectionofroutersunderthecontrolofasingleadministrativeauthorityandthatusesacommonInteriorGatewayProtocol.

29.WhatisEGP(ExteriorGatewayProtocol)?Itistheprotocoltheroutersinneighboringautonomoussystemsusetoidentifythesetofnetworksthatcanbereachedwithinorviaeachautonomoussystem.

30.WhatisIGP(InteriorGatewayProtocol)?Itisanyroutingprotocolusedwithinanautonomoussystem.

31.WhatisMailGateway?Itisasystemthatperformsaprotocoltranslationbetweendifferentelectronicmaildeliveryprotocols.

32.Whatiswidemouthfrog?Widemouthfrogisthesimplestknownkeydistributioncenter(KDC)authenticationprotocol.

33.WhatareDigramsandTrigrams?Themostcommontwolettercombinationsarecalledasdigrams.e.g.th,in,er,reandan.Themostcommonthreelettercombinationsarecalledastrigrams.e.g.the,ing,and,andion.

34.Whatissillywindowsyndrome?ItisaproblemthatcanruinTCPperformance.ThisproblemoccurswhendataarepassedtothesendingTCPentityinlargeblocks,butaninteractiveapplicationonthereceivingsidereads1byteatatime.

35.Whatisregion?Whenhierarchicalroutingisused,theroutersaredividedintowhatwecallregions,witheachrouterknowingallthedetailsabouthowtoroutepacketstodestinationswithinitsownregion,butknowingnothingabouttheinternalstructureofotherregions.

36.Whatismulticastrouting?Sendingamessagetoagroupiscalledmulticasting,anditsroutingalgorithmiscalledmulticastrouting.

37.Whatistrafficshaping?Oneofthemaincausesofcongestionisthattrafficisoftenbusy.Ifhostscouldbemadetotransmitatauniformrate,congestionwouldbelesscommon.Anotheropenloopmethodtohelpmanagecongestionisforcingthepackettobetransmittedatamorepredictablerate.Thisiscalledtrafficshaping.

38.Whatispacketfilter?Packetfilterisastandardrouterequippedwithsomeextrafunctionality.Theextrafunctionalityallowseveryincomingoroutgoingpackettobeinspected.Packetsmeetingsomecriterionareforwardednormally.Thosethatfailthetestaredropped.

39.Whatisvirtualpath?Alonganytransmissionpathfromagivensourcetoagivendestination,agroupofvirtualcircuitscanbegroupedtogetherintowhatiscalledpath.

40.Whatisvirtualchannel?Virtualchannelisnormallyaconnectionfromonesourcetoonedestination,althoughmulticastconnectionsarealsopermitted.Theothernameforvirtualchannelisvirtualcircuit.

41.Whatislogicallinkcontrol?



OneoftwosublayersofthedatalinklayerofOSIreferencemodel,asdefinedbytheIEEE802standard.Thissublayerisresponsibleformaintainingthelinkbetweencomputerswhentheyaresendingdataacrossthephysicalnetworkconnection.

42.WhyshouldyoucareabouttheOSIReferenceModel?Itprovidesaframeworkfordiscussingnetworkoperationsanddesign.

43.Whatisthedifferencebetweenroutableandnonroutableprotocols?Routableprotocolscanworkwitharouterandcanbeusedtobuildlargenetworks.NonRoutableprotocolsaredesignedtoworkonsmall,localnetworksandcannotbeusedwitharouter.

44.WhatisMAU?IntokenRing,hubiscalledMultistationAccessUnit(MAU).

45.Explain543rule?InaEthernetnetwork,betweenanytwopointsonthenetwork,therecanbenomorethanfivenetworksegmentsorfourrepeaters,andofthosefivesegmentsonlythreeofsegmentscanbepopulated.

46.WhatisthedifferencebetweenTFTPandFTPapplicationlayerprotocols?TheTrivialFileTransferProtocol(TFTP)allowsalocalhosttoobtainfilesfromaremotehostbutdoesnotprovidereliabilityorsecurity.ItusesthefundamentalpacketdeliveryservicesofferedbyUDP.TheFileTransferProtocol(FTP)isthestandardmechanismprovidedbyTCP/IPforcopyingafilefromonehosttoanother.ItusestheservicesofferedbyTCPandsoisreliableandsecure.Itestablishestwoconnections(virtualcircuits)betweenthehosts,onefordatatransferandanotherforcontrolinformation.

47.Whatistherangeofaddressesintheclassesofinternetaddresses?ClassA0.0.0.0127.255.255.255ClassB128.0.0.0191.255.255.255ClassC192.0.0.0223.255.255.255ClassD224.0.0.0239.255.255.255ClassE240.0.0.0247.255.255.255

48.WhatistheminimumandmaximumlengthoftheheaderintheTCPsegmentandIPdatagram?Theheadershouldhaveaminimumlengthof20bytesandcanhaveamaximumlengthof60bytes.

49.WhatisdifferencebetweenARPandRARP?Theaddressresolutionprotocol(ARP)isusedtoassociatethe32bitIPaddresswiththe48bitphysicaladdress,usedbyahostoraroutertofindthephysicaladdressofanotherhostonitsnetworkbysendingaARPquerypacketthatincludestheIPaddressofthereceiver.Thereverseaddressresolutionprotocol(RARP)allowsahosttodiscoveritsInternetaddresswhenitknowsonlyitsphysicaladdress.

50.WhatisICMP?ICMPisInternetControlMessageProtocol,anetworklayerprotocoloftheTCP/IPsuiteusedbyhostsandgatewaystosendnotificationofdatagramproblemsbacktothesender.Itusestheechotest/replytotestwhetheradestinationisreachableandresponding.Italsohandlesbothcontrolanderrormessages.

51.WhatarethedataunitsatdifferentlayersoftheTCP/IPprotocolsuite?Thedataunitcreatedattheapplicationlayeriscalledamessage,atthetransportlayerthedataunitcreatediscalledeitherasegmentoranuserdatagram,atthenetworklayerthedataunitcreatediscalledthedatagram,atthedatalinklayerthedatagramisencapsulatedintoaframeandfinallytransmittedassignalsalongthetransmissionmedia.



52.WhatisProject802?ItisaprojectstartedbyIEEEtosetstandardsthatenableintercommunicationbetweenequipmentfromavarietyofmanufacturers.Itisawayforspecifyingfunctionsofthephysicallayer,thedatalinklayerandtosomeextentthenetworklayertoallowforinterconnectivityofmajorLANprotocols.Itconsistsofthefollowing:802.1isaninternetworkingstandardforcompatibilityofdifferentLANsandMANsacrossprotocols.802.2Logicallinkcontrol(LLC)istheuppersublayerofthedatalinklayerwhichisnonarchitecturespecific,thatisremainsthesameforallIEEEdefinedLANs.Mediaaccesscontrol(MAC)isthelowersublayerofthedatalinklayerthatcontainssomedistinctmoduleseachcarryingproprietaryinformationspecifictotheLANproductbeingused.ThemodulesareEthernetLAN(802.3),TokenringLAN(802.4),TokenbusLAN(802.5).802.6isdistributedqueuedualbus(DQDB)designedtobeusedinMANs.

53.WhatisBandwidth?Everylinehasanupperlimitandalowerlimitonthefrequencyofsignalsitcancarry.Thislimitedrangeiscalledthebandwidth.

54.Differencebetweenbitrateandbaudrate.Bitrateisthenumberofbitstransmittedduringonesecondwhereasbaudratereferstothenumberofsignalunitspersecondthatarerequiredtorepresentthosebits.baudrate=bitrate/NwhereNisnoofbitsrepresentedbyeachsignalshift.

55.WhatisMACaddress?TheaddressforadeviceasitisidentifiedattheMediaAccessControl(MAC)layerinthenetworkarchitecture.MACaddressisusuallystoredinROMonthenetworkadaptercardandisunique.

56.Whatisattenuation?Thedegenerationofasignaloverdistanceonanetworkcableiscalledattenuation.

57.Whatiscladding?Alayerofaglasssurroundingthecenterfiberofglassinsideafiberopticcable.

58.WhatisRAID?Amethodforprovidingfaulttolerancebyusingmultipleharddiskdrives.

59.WhatisNETBIOSandNETBEUI?NETBIOSisaprogramminginterfacethatallowsI/Orequeststobesenttoandreceivedfromaremotecomputerandithidesthenetworkinghardwarefromapplications.NETBEUIisNetBIOSextendeduserinterface.AtransportprotocoldesignedbymicrosoftandIBMfortheuseonsmallsubnets.

60.Whatisredirector?RedirectorissoftwarethatinterceptsfileorprintsI/Orequestsandtranslatesthemintonetworkrequests.Thiscomesunderpresentationlayer.

61.WhatisBeaconing?Theprocessthatallowsanetworktoselfrepairnetworksproblems.Thestationsonthenetworknotifytheotherstationsontheringwhentheyarenotreceivingthetransmissions.BeaconingisusedinTokenringandFDDInetworks.

62.Whatisterminalemulation,inwhichlayeritcomes?Telnetisalsocalledasterminalemulation.Itbelongstoapplicationlayer.

63.Whatisframerelay,inwhichlayeritcomes?



Framerelayisapacketswitchingtechnology.Itwilloperateinthedatalinklayer.

64.Whatdoyoumeantby"tripleX"inNetworks?ThefunctionofPAD(PacketAssemblerDisassembler)isdescribedinadocumentknownasX.3.ThestandardprotocolhasbeendefinedbetweentheterminalandthePAD,calledX.28anotherstandardprotocolexistsbetweenhtePADandthenetwork,calledX.29.Together,thesethreerecommendationsareoftencalled"tripleX"

65.WhatisSAP?Seriesofinterfacepointsthatallowothercomputerstocommunicatewiththeotherlayersofnetworkprotocolstack.

66.Whatissubnet?Agenerictermforsectionofalargenetworksusuallyseparatedbyabridgeorrouter.

67.WhatisBrouterHybriddevicesthatcombinethefeaturesofbothbridgesandrouters.

68.HowGatewayisdifferentfromRouters?AgatewayoperatesattheupperlevelsoftheOSImodelandtranslatesinformationbetweentwocompletelydifferentnetworkarchitecturesordataformats.

69.Whatarethedifferenttypeofnetworking/internetworkingdevices?Repeater:Alsocalledaregenerator,itisanelectronicdevicethatoperatesonlyatphysicallayer.Itreceivesthesignalinthenetworkbeforeitbecomesweak,regeneratestheoriginalbitpatternandputstherefreshedcopybackintothelink.

Bridges:TheseoperatebothinthephysicalanddatalinklayersofLANsofsametype.Theydividealargernetworkintosmallersegments.Theycontainlogicthatallowthemtokeepthetrafficforeachsegmentseparateandthusarerepeatersthatrelayaframeonlythesideofthesegmentcontainingtheintendedrecipentandcontrolcongestion.

Routers:Theyrelaypacketsamongmultipleinterconnectednetworks(i.e.LANsofdifferenttype).Theyoperateinthephysical,datalinkandnetworklayers.Theycontainsoftwarethatenablethemtodeterminewhichoftheseveralpossiblepathsisthebestforaparticulartransmission.

Gateways:Theyrelaypacketsamongnetworksthathavedifferentprotocols(e.g.betweenaLANandaWAN).Theyacceptapacketformattedforoneprotocolandconvertittoapacketformattedforanotherprotocolbeforeforwardingit.TheyoperateinallsevenlayersoftheOSImodel.

70.Whatismeshnetwork?Anetworkinwhichtherearemultiplenetworklinksbetweencomputerstoprovidemultiplepathsfordatatotravel.

71.Whatispassivetopology?Whenthecomputersonthenetworksimplylistenandreceivethesignal,theyarereferredtoaspassivebecausetheydontamplifythesignalinanyway.Exampleforpassivetopologylinearbus.

72.Whataretheimportanttopologiesfornetworks

BUStopology:Inthiseachcomputerisdirectlyconnectedtoprimarynetworkcableinasingleline.Advantages:Inexpensive,easytoinstall,simpletounderstand,easytoextend.



STARtopology:Inthisallcomputersareconnectedusingacentralhub.Advantages:Canbeinexpensive,easytoinstallandreconfigureandeasytotroubleshootphysicalproblems.

RINGtopology:Inthisallcomputersareconnectedinloop.Advantages:Allcomputershaveequalaccesstonetworkmedia,installationcanbesimple,andsignaldoesnotdegradeasmuchasinothertopologiesbecauseeachcomputerregeneratesit.

73.Whataremajortypesofnetworksandexplain?ServerbasednetworkPeertopeernetworkPeertopeernetwork,computerscanactasbothserverssharingresourcesandasclientsusingtheresources.Serverbasednetworksprovidecentralizedcontrolofnetworkresourcesandrelyonservercomputerstoprovidesecurityandnetworkadministration

74.WhatisProtocolDataUnitThedataunitintheLLCleveliscalledtheprotocoldataunit(PDU).ThePDUcontainsoffourfieldsadestinationserviceaccesspoint(DSAP),asourceserviceaccesspoint(SSAP),acontrolfieldandaninformationfield.DSAP,SSAPareaddressesusedbytheLLCtoidentifytheprotocolstacksonthereceivingandsendingmachinesthataregeneratingandusingthedata.ThecontrolfieldspecifieswhetherthePDUframeisainformationframe(Iframe)orasupervisoryframe(Sframe)oraunnumberedframe(Uframe).

75.Whatisdifferencebetweenbasebandandbroadbandtransmission?Inabasebandtransmission,theentirebandwidthofthecableisconsumedbyasinglesignal.Inbroadbandtransmission,signalsaresentonmultiplefrequencies,allowingmultiplesignalstobesentsimultaneously.

76.Whatarethepossiblewaysofdataexchange?(i)Simplex(ii)Halfduplex(iii)Fullduplex.

77.WhatarethetypesofTransmissionmedia?Signalsareusuallytransmittedoversometransmissionmediathatarebroadlyclassifiedintotwocategories.GuidedMedia:Thesearethosethatprovideaconduitfromonedevicetoanotherthatincludetwistedpair,coaxialcableandfiberopticcable.Asignaltravelingalonganyofthesemediaisdirectedandiscontainedbythephysicallimitsofthemedium.Twistedpairandcoaxialcableusemetallicthatacceptandtransportsignalsintheformofelectricalcurrent.Opticalfiberisaglassorplasticcablethatacceptsandtransportssignalsintheformoflight.UnguidedMedia:Thisisthewirelessmediathattransportelectromagneticwaveswithoutusingaphysicalconductor.Signalsarebroadcasteitherthroughair.Thisisdonethroughradiocommunication,satellitecommunicationandcellulartelephony.

78.Differencebetweenthecommunicationandtransmission.Transmissionisaphysicalmovementofinformationandconcernissueslikebitpolarity,synchronization,clocketc.Communicationmeansthemeaningfullexchangeofinformationbetweentwocommunicationmedia.

79.TheInternetControlMessageProtocoloccursatwhatlayerofthesevenlayermodel?Network

80.WhichprotocolresolvesanIPaddresstoaMACaddress?ARP

81.MIDIandMPEGareexamplesofwhatlayeroftheOSIsevenlayermodel?



PostedbyDharanyaat11:07PM 5comments:

Labels:ComputerNetworks:Interview,VivaandBasicQuestionsPart4

Presentation

82.WhatistheprotocolnumberforUDP?17

83.Whichprotocolisusedforbootingdisklessworkstations?RARP

84.Whichlayerisresponsibleforputting1sand0sintoalogicalgroup?Physical

85.Whatdoes'P'meanwhenrunningaTrace?Protocolunreachable

86.UDPworksatwhichlayeroftheDODmodel?HosttoHost

87.WhatisthedefaultencapsulationofNetware3.12?802.2

88.PinguseswhichInternetlayerprotocol?ICMP

89.Whichswitchingtechnologycanreducethesizeofabroadcastdomain?VLAN

90.Whatisthefirststepindataencapsulation?Userinformationisconvertedintodata.

91.WhatistheprotocolnumberforTCP?6

92.WhatdoyouusetheAuxportfor?Modem

93.RepeatersworkatwhichlayeroftheOSImodel?Physical

94.WANstandsforwhichofthefollowing?WideAreaNetwork

95.WhatISDNprotocolspecifiesconcepts,terminology,andservices?I

96.LANstandsforwhichofthefollowing?LocalAreNetwork

97.DHCPstandsforDynamicHostConfigurationProtocol

98.WhatdoestheacronymARPstandfor?AddressResolutionProtocol

99.Whichlayerisresponsibleforidentifyingandestablishingtheavailabilityoftheintendedcommunicationpartner?Application.

100.WhichOSIlayerprovidesmechanical,electrical,proceduralforactivating,maintainingphysicallink?Physical

Recommend this on Google



OlderPostsHome

Subscribeto:Posts(Atom)

Referthissite2urfrndz

DharanyadeviBlogSpot.Simpletemplate.PoweredbyBlogger.

Documents

_Here to Help You__ Computer Networks_ Interview