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Gigabit Ethernet



Introduction

DevelopmentStatus

GigabitEthernetisatechnologybasedonbasicEthernetstandards.GigabitEthernetandthewidelyusedEthernetarefullycompatiblewithFastEthernet,anduseallthetechnicalspecificationsstipulatedbytheoriginalEthernetstandard,includingCSMA/CDprotocol,Ethernetframe,fullduplex,flowcontrolandIEEE802.3Managementobjectsdefinedinthestandard.AsanintegralpartofEthernet,GigabitEthernetalsosupportstrafficmanagementtechnology,whichguaranteesthequalityofserviceonEthernet.ThesetechnologiesincludeIEEE802.1Player2priority,layer3priorityQoScodingbits,specialServiceandResourceReservationProtocol(RSVP).

GigabitEthernetalsoutilizesIEEE802.1QVLANsupport,fourth-levelfiltering,andGigabitthird-levelswitching.GigabitEthernetwasoriginallydesignedasaswitchingtechnology,usingopticalfiberastheuplinkforconnectionsbetweenbuildings.Later,intheconnectionofserversandbackbonenetworks,GigabitEthernethasbeenwidelyused.DuetotheintroductionoftheIEEE802.3abstandard(GigabitEthernetstandardusingcategory5andaboveunshieldedtwistedpair),GigabitEthernetcanbeused.Applicabletoanylarge,mediumandsmallenterprisesandinstitutions.

GigabitEthernethasdevelopedintoamainstreamnetworktechnology.Largeenterprisesaslargeastensofthousandsofpeople,smallandmedium-sizedenterprisesassmallasdozensofpeople,willuseGigabitEthernettechnologyasthepreferredhigh-speednetworktechnologywhenbuildingcorporateLANs.GigabitEthernettechnologyisevenreplacingATMtechnology,becomingthemainforceintheconstructionofmetropolitanareanetworks.

Features

1.GigabitEthernetprovidesaperfectmigrationpath,fullyprotectingtheinvestmentintheexistingnetworkinfrastructure.GigabitEthernetwillretainIEEE802.3andEthernetframeformatsand802.3managedobjectspecifications,sothatenterprisescanupgradetogigabitperformancewhileretainingexistingcables,operatingsystems,protocols,anddesktopapplicationsProgramandnetworkmanagementstrategiesandtools;

2.ComparedwiththeoriginalbackbonenetworksolutionssuchasFastEthernet,FDDI,andATM,GigabitEthernetprovidesanoptimalpath.Atleastfornow,itisareliableandeconomicalwaytoimprovethebackboneconnectionbetweentheswitchandtheswitchandtheconnectionbetweentheswitchandtheserver.Networkdesignerscanbuildahigh-speedinfrastructurethateffectivelyuseshigh-speed,mission-criticalapplicationsandfilebackups.NetworkmanagerswillprovideuserswithfasteraccesstotheInternet,Intranet,MetropolitanAreaNetworkandWideAreaNetwork.

3.TheIEEE802.3workinggroupestablishedthe802.3zand802.3abGigabitEthernetworkinggroups,whosetaskistodevelopGigabitEthernetstandardsthatmeetdifferentneeds.Thisstandardsupportsfull-duplexandhalf-duplex1000Mbps,andthecorrespondingoperationadoptsIEEE802.3EthernetframeformatandCSMA/CDmediaaccesscontrolmethod.GigabitEthernetisalsobackwardcompatiblewith10BaseTand100BaseT.Inaddition,theIEEEstandardwillsupportmultimodefiberswithamaximumdistanceof550meters,single-modefiberswithamaximumdistanceof70kilometers,andcoppercableswithamaximumdistanceof100meters.GigabitEthernetfillsinthedeficienciesofthe802.3Ethernet/FastEthernetstandard.

Construction

TheGigabitEthernetnetworkiscomposedofGigabitswitches,Gigabitnetworkcards,andintegratedwiringsystems.Thegigabitswitchformsthebackboneofthenetwork.Thegigabitnetworkcardisinsertedintotheserverandconnectedtotheswitchthroughawiringsystem.Therecanalsobemany100Mswitchesunderthegigabitswitch,andthe100Mswitchisconnectedtotheworkstation.Thisistheso-called"100MTothedesktop".Insomeprofessionalgraphicsproductionandvideo-on-demandapplications,"GigabittoDesktop"mayalsobeused,andaGigabitswitchisusedtoconnecttoaworkstationwithaGigabitnetworkcard,whichmeetsthedemandforhighbandwidthunderspecialapplications.

Beforebuildinganetwork,whethertouseGigabitor100M,wemuststartfromtheactualsituation,startfromtheapplication,andconsiderwhatfunctionsthenetworkshouldhave.Differentapplicationshavedifferentrequirements,andthereisalmostnonetworkwithasingleservice.However,amongthevariousbusinesses,theproductivebusinessisdefinitelythehighestpriority.Ifvoiceistransmittedoverthenetwork,thenvoiceservicesalsoneedtobeprioritized.Ifthedemandforbusinesspriorityishigh,thenetworkmusthaveQoSguarantees.Suchanetworkmustbeintelligent.Theswitchportcanidentifywhattypesofservicesarepassing,andthenqueueupdifferentservices,andallocatedifferentbandwidthsfordifferentservices,soastoensuretheoperationofkeyservices.Thedataserviceitselfisintelligent,anditcanbetransmittednomatterhowmuchbandwidthitis,justthelengthoftime,butthevoiceorvideoisnotthesame.Ifthebandwidthissmall,itwillbedifficulttohearimmediately,ortheimagewillbejittery.notallowed.SoQoSisveryimportant.Forapuredatanetwork,thedemandforQoSisverylow.Whenplanningthenetwork,youmustfirstunderstandwhichfunctionsarenecessaryandwhichcannotbeconsidered.Forexample,multicastingisoneofthemoreimportantfeatures.Ifimagesneedtobetransmittedonthenetwork,andthenetworkdoesnothavethecharacteristicsofmulticasting,thebandwidthwasteofthenetworkwillbeveryserious,orevenimpossibletoachieve.

Kansainvälinen standardi

Tammikuussa 1997 IEEE802.3z:n ensimmäinen luonnos hyväksyttiin;

Kesäkuussa 1997 luonnos V3.1 hyväksyttiin. Lopulliset tekniset tiedot on muotoiltu tässä;

Kesäkuussa 1998 IEEE802.3z-standardi hyväksyttiin virallisesti;

Kesäkuussa 1999 IEEE802.3abstandardi(ie1000Base-T) hyväksyttiin virallisesti.Voit käyttää kierrettyjä parikaapeleita GigabitEthernetille.

TheGigabitEthernetstandardmainlytargetsthreetypesoftransmissionmedia:single-modefiber;long-wavelaseronmulti-modefiber(called1000BaseLX),short-wavelaseronmulti-modefiber(called1000BaseSX));1000BaseCXmedium,whichcanbetransmittedonabalancedshielded150ohmcoppercable.The1000BaseTstandardsimulatedbytheIEEE802.3zcommitteeallowsthetransmissiondistanceofGigabitEthernetonCategory5,Super5,andCategory6UTPtwisted-pairlinestobeextendedto100meters,sothatmostofthewiringinthebuildingadoptsCategory5UTPtwistedpaircableguaranteestheuser'spreviousinvestmentinEthernetandFastEthernet.Fornetworkadministrators,thereisnoneedtoacceptnewtraining.WiththeknowledgeofEthernetnetworks,theycanmanageandmaintainGigabitEthernet.

ThestandardizationofGigabitEthernetincludesthreemainmodules:encoding/decoding,transceiver,andnetworkmedia.Differenttransceiverscorrespondtodifferentnetworkmediatypes.When1000BASE-LXisbasedonthe1300nmsingle-modeopticalcablestandard,ituses8B/10Bencodinganddecoding,andthemaximumtransmissiondistanceis5000meters.1000BASE-SXisbasedon780nmFibreChanneloptics,using8B/10Bencodinganddecodingmethods,using50micronor62.5micronmultimodeopticalcables,andthemaximumtransmissiondistanceis300metersto500meters.TheSCtypeopticalfiberconnectorusedtoconnecttheopticalfiberisofthesamemodelastheconnectorusedinFastEthernet100BASEFX.1000BASE-CXisastandardbasedoncoppercables,using8B/10Bencodinganddecodingmethods,withamaximumtransmissiondistanceof25meters.1000BASE-Tisbasedonunshieldedtwistedpairtransmissionmedium,using1000BASE-TcopperphysicallayerCopperPHYencodinganddecodingmethod,thetransmissiondistanceis100meters.1000BASE-Tusesall4twistedpairsintransmissionandworksinfullduplexmode.ThisdesignusesPAM-5(5-levelpulseamplificationmodulation)encodingtotransmit250Mbpsoneachpair.Two-waytransmissionrequiresthatallfourwire-pairtransceiverportsmustuseahybridmagneticfieldcircuit.Becauseaperfecthybridmagneticfieldcircuitcannotbeprovided,itisimpossibletocompletelyisolatethetransmittingandreceivingcircuits.Anysendingandreceivinglineswillechotheequipment.Therefore,toachievetherequirederrorrate(BER),theechomustbecanceled.1000BASE-Tcannotfilterthefrequencybandsabove125MHz,buttheuseofscramblingtechnologyandtrelliscodingcanfilterthefrequencybandsafter80MHz.InordertosolvethelimitationofCategory5linesduetonear-endcrosstalkinsuchahighfrequencyrange,appropriatesolutionsshouldbeadoptedtooffsetthecrosstalk.

TheoriginalGigabitEthernetusedhigh-speed780nmfiberchannelopticalcomponentstotransmitsignalsonopticalfibers,andused8B/10Bencodinganddecodingmethodstoachieveserializationandrestorationofopticalsignals.ThedataoperatingrateofFibreChanneltechnologyis1.063Gbps,whichwillbeincreasedto1.250Gbpsinthefuture,enablingthedataratetoreachacomplete1000Mbps.Forlongerconnectiondistances,1300nmopticalcomponentswillbeused.Inordertoadapttothedevelopmentofsilicontechnologyanddigitalsignalprocessingtechnology,amedium-independentlogicalinterfaceshouldbeestablishedbetweentheMAClayerandthePHYlayer,sothatGigabitEthernetcanworkinanunshieldedtwistedpaircablesystem.Thislogicalinterfacewillbeapplicabletotheencodingmethodofunshieldedtwistedpaircablesystemsandisindependentoftheencodingmethodoffiberchannel.ThefollowingfigureillustratesthecompositionofGigabitEthernet.

GigabitEthernet

Therearenotmanyconditionsforupgrading10Mand100MnetworkstoGigabit.Themostimportantthingistheintegratedwiringconditions.GigabitEthernetreferstothebandwidthofthenetworkbackbone,andthebackbonecablingsystemmustmeettherequirementsofGigabitEthernet.Iftheoriginalnetworkcoversmultiplebuildingsseparatedbyseveralhundredmeterstoseveralkilometers,theoriginalbackbonewiringgenerallyusesmulti-modeorsingle-modefiber,whichcanmeettherequirementsofagigabitbackbone,andthereisnoneedtore-laythefiber.Whenthedistancebetweenbuildingsislessthan550meters,generallylayingrelativelyinexpensivemulti-modeopticalfibercanmeettheneedsofGigabitEthernet.

Iftheoriginalnetworkonlycoversonebuilding,andthedistancebetweenthefurthestnetworknodeandthenetworkcenterisnomorethan100meters,theoriginalCategory5orCategory5cablingsystemcanbeused.IftheoriginalwiringsystemdoesnotmeettheCategory5standard,orifabus-typewiringsystemisusedinsteadofastar-typewiringsystem,thenCategory5linesmustbere-routed.

ToupgradetoGigabitEthernet,youmustfirstupgradethenetworkbackboneswitchtoGigabittoincreasethedatatrafficthatthenetworkbackbonecanwithstand,soastoachievethepurposeofacceleratingthenetworkspeed.Theprevious100Mswitcheswereusedasbranchswitches,andtheprevioushubscanbeusedwherethereareinsufficientwiringpoints.TherearemanyGigabitswitchproducts,whichcanbeselectedaccordingtoactualconditionssuchasnetworkrequirementsandbudgets.

Theserveronthenetworkneedstohandlealotofdata.Ifthenetworkbackboneisupgradedtogigabit,buttheservernetworkcardisstillatthelevelof100M,theservernetworkcardwillbecomethebottleneckofthenetwork,andgigabitmustbeusedThenetworkcardcaneliminatethisbottleneck.Thesolutionistoaddagigabitnetworkcardtotheoriginalserver.Notethat64-bitPCIGigabitnetworkcardsshouldbeselectedfirst,anditsperformanceishigherthanordinaryPCIGigabitnetworkcards.Gigabitnetworkcardcanbeselectedaccordingtoactualconditionssuchasnetworkrequirementsandbudget.

Thebackboneofthenetworkhasbeenupgraded,andthebranchesofthenetworkshouldbeupgradedaccordingly.Iftheoriginalusercomputerhasalreadyinstalleda10M/100Madaptivenetworkcard,youdon’tneedtoupgradethenetworkcard,justconnectthenetworkcardtoa100Mswitch;iftheoriginal10Mbpsnetworkcardisused,youneedtochangethenetworkcardto10M/100Madaptivenetworkcard,soastoincreasethespeedofworkstationsaccessingtheserver.

Prospectforecast

Itisestimatedthatbefore2005,thedatatransmissionvolumewillincreaseby3timeseachyear,andwillexceedthevoicetransmissionvolumethatyear,becomingthemaintransmissionmethodofglobalcommunicationnetwork.Inthefaceofever-increasingdatastreamsandmultimediaservices,themarketscaleofhigh-endnetworkproductswithlarge-capacity,high-speed,andmulti-functionmoduleswillcontinuetoexpand.ItisforeseeablethatthemarketshareofGigabitEthernetswitcheswillbecomelargerandlarger.WiththedevelopmentoftheInternetandtheemergenceofendlessapplicationsonthenetwork,10GigabitEthernetwillbethemainstreaminthefuture,andGigabitEthernetwillstillbethemainstreaminthemarket.

Technicaladvantages

Inordertomaintainthemaximumcollisionareawithadiameterof200metersandtheminimumCSMA/CDcarriertimeinthelocalareanetwork,theEthernettimeslicehasbeenextendedfrom512bitsto512bytes(4096bits),theminimumframelengthbecomes512bytes,andthemaximumframelengthisstill1518bytes.ThecarrierextensionfeaturesolvestheinherenttimingproblemofCSMA/CDwithoutmodifyingtheminimumpacketsize.Althoughthesechangesmayaffecttheperformanceofsmallinformationpackets,thiseffecthasbeenoffsetbyacharacteristiccalledpacketbursttransferintheCSM/CDalgorithm.ThebiggestadvantageofGigabitEthernetisitscompatibilitywithexistingEthernet.

Like100M-bitEthernet,GigabitEthernetusesthesameframeformatandframesizeas10M-bitEthernet,andthesameCSMA/CDprotocol.ThismeansthatthemajorityofEthernetuserscanupgradetheexistingEthernetsmoothlyandwithoutinterruptionwithoutaddingadditionalprotocolstacksormiddleware.Atthesametime,GigabitEthernetalsoinheritsotheradvantagesofEthernet,suchashighreliabilityandeasymanagement.

Comparedwithothertechnologies,GigabitEthernethastheadvantageoflargebandwidthandstillhasroomfordevelopment.Therelevantstandardsorganizationsareformulatingtechnicalspecificationsandstandardsfor10GEthernet.Atthesametime,prioritycontrolmechanismsandprotocolstandardsbasedontheEthernetframelayerandIPlayer,aswellasvariousQoSsupporttechnologieshavegraduallymatured,providingafoundationfortheimplementationofapplicationsrequiringbetterservicequality.Withtheadvancementofopticalfibermanufacturingandtransmissiontechnology,thetransmissiondistanceofGigabitEthernetcanreachupto100kilometers,whichmakesitgraduallybecomeatechnologychoiceforbuildingmetropolitanareanetworksandevenwideareanetworks.

TheadvantageofusingGigabitEthernetinthebackboneisthatGigabitEthernetwillprovide10timestheperformanceofFastEthernetandiscompatiblewiththeexisting10/100Ethernetstandard.Atthesametime,thevirtualnetworkstandard802.1Qandprioritystandard802.1pdevelopedfor10/100/1000Mbpshavebeenpromoted,andthegigabitnetworkhasbecomethemainstreamtechnologythatformsthebackboneofthenetwork.

ThefirstGigabitEthernetstandard802.3,whichwasformulatedinJune1998,targetsfull-duplexlinksusingopticalfibercablesandshort-distancecoppercables.Thestandard802.3abforhalf-duplexandremotecopperwirecableswasintroducedin1999.

Thehigh-speedmulti-layerdatapacketforwardingcapabilityofGigabitEthernetisapowerfulexamplethatGigabitEthernettechnologycanprovidethebestperformance-to-priceratio.Notonlythat,GigabitEthernettechnologyisalsoverybeneficialforreducingthelong-termcostofownershipofthenetwork.

Switchingtechnology

Sincetheendof1996,somecompanieshavesuccessivelyintroducedswitchproductsthatintegratelayer2switchingandlayer3routing.Thistechnologyiscalled"multi-layerswitching(multilayerswitching)".Itaddsroutinglayerservicestolayer2switchingtechnology,supportsselectivebroadcastandmulticastsuppression,supportspacketforwardingandfirewallfunctionsbetweenVLANsandVLANs,andfullysupportsTCP/IPandIPXrouting.

Afternearly4yearsofdevelopment,thesefunctionshavebeencontinuouslyimprovedandstrengthened,makingtheperformance-priceratioofmulti-layerswitches8to16timeshigherthantraditionalrouters.Thenewgenerationofmulti-layerswitcheswithGigabitEthernetswitchingtechnologyasthecore,canprovidemoreattractiveperformance-priceratio,andisthemostidealswitchthatcanprovidemulti-layerswitchingindepartmentalnetworksanddatacenternetworkstoreplacetraditionalrouters.Atthesametime,itsdirecttransmissiondistancehasnowreached130kilometers,whichcanfullyrealizealargeenterpriseLANwithGigabitEthernetasthebackbone,andthebackbonetransmissionrateis2Gbps(fullduplexmode).

ThemainfactorthatpromotesthedevelopmentoftechnologyThebiggestfactorthatpromotesthedevelopmentofhigh-speedmulti-layerswitchingtechnologyisthemassdeploymentoftheInternetandIntranetusingcheap10/100Madaptivenetworkcards.Thenetworkhasbecomefartherandfartherawayfromthetraditionalc/scomputingmodel'shierarchicalstructure,andthetraditional80/20trafficruleofthec/smodelhasbecomeathingofthepast.Intermsofnetworkdesign,thetraditionalrouterplusHuborLayer2switchnetworkdeploymentmodelwillalsobecomehistory.

Lisäksi Intranet tukee monenlaisia ​​monimutkaisempia ja kaistanleveysherkempiä multimediatietovirtoja, kuten dataa, tiedostoja, kuvia, animaatioita, ääntä ja videota. menttrendi.

AnotherissueworthnotingisthatprovidinguserswithafastEthernetconnectioncanprovidemorebandwidthmargintohandlesuddentraffic,whichisunmatchedby10BASE-Ttechnology.BursttrafficisoneofthecharacteristicsofIPnetworkapplications.LowcostandhighbandwidthmakeFastEthernetwidelyusedonboththeusersideandtheserverside.

Inordertostrikeabalancebetweennon-blockingandtheabilitytohandlesuddentrafficflows,thenewgenerationofswitchplatformsmustprovidebackboneconnectionsthatare8-16timesfasterthantheuser’srequestconnection.ThenetworkbackbonejustsatisfiestheservicerequestofthefastEthernetconnectionontheuserside.Thisisveryimportanttoadequatelyhandlebursttraffic.

Atthesametime,incampusnetworksormetropolitanareanetworks,nomatterhowmanynetworklayersarespanned,randomintranettrafficisrequiredtoprovideend-to-endconsistenthighperformance.Inordertoachievethis,itistheonlysolutiontohavebothhigh-performancelayer2andlayer3forwardingcapabilitiesinaswitch.

Thenon-blockingcapabilityandselectiveforwardingfunctionarethemainrequirementsofusers.Variousveryeffectivenetworkmanagementtoolsenablenetworkadministratorstoeffectivelyandefficientlyinjectbusinessstrategiesintotheforwardingengine,anditsperformancecanbemonitoredinrealtimethroughnetworkmanagementsoftware.Thiswillfundamentallyhelpusersdetermineanddelivertherequirednetworkservicesaccordingtothecompany'sshort-termandlong-termbusinessdevelopmentneeds.ThenewgenerationofGigabitEthernetswitchessupportthesefeaturesandservices,aswellascommonroutingprotocolssuchasIP/RIPorIP/OSPF.Thisalsogreatlyreducesthecomplexityofnetworkequipment.

Objectiveprinciples

Thehighperformanceofthenetworksystemrequiresthecoreswitchtomeettherequirementsofthemassivedataexchangeofthenetworkcenter,andthecommunicationlinkbandwidthoftheuplinkcentercanmeettheperformancerequirementsoftheapplicationonthenetwork.Regardlessofwhetheritisanenterprisenetwork,ametropolitanareanetwork,orawideareanetwork,theinformationapplicationsonitaredevelopingatanunprecedentedspeed,andnewmultimediaapplicationsandnewdataapplicationsplacehigherrequirementsonbandwidth.Inthecaseofenterprisesgenerallyadoptingtheintranetnetworkmodel,itsWWWserver,FTPserver,LotusNotesgroupwareapplicationserver,NovellServerandotherserverclusterssupporttheentireenterprise'sinformationserviceenvironment.Theclientapplicationsoftwareofusersinvariousdepartmentsoftheenterpriseaccessesthecentralserverthroughthenetwork,requestsapplications,andqueriesthedatabase.Theloadflowofthenetworkismainlythedataexchangefromtheedgedevicetothecore.Withthedevelopmentofenterprisebusiness,theexpansionofthenetworkscale,andtheincreaseintheamountofinformationexchangeoftheapplication,theenterprisenetworkusuallyfirstoccursinthecoreofthecommunicationbottleneckphenomenon.ToimprovethenetworkdataexchangeperformanceoftheenterprisecampusLAN,thefirststepistoexpandtheexchangeperformanceofthecoreswitchandincreasethedatacommunicationbandwidthfromtheedgedevicetothecoretoreducethebottleneckoftheentirenetworkandimprovetheperformanceandefficiencyofapplicationsoftware.Therefore,intheprincipleofdesigninganenterprisecampusLAN,weshouldfirstconsiderthedataexchangeprocessingcapabilitiesofthecoreequipmentrequiredbythenetworkscale,andthelinkbandwidthfromtheedgeequipmenttothecore.

Reliabilityandavailability

Thehighreliabilityofequipmentandhighavailabilityofthesysteminthenetworksystemdesign;allkeycomponentsofthecoreswitcharerequiredtoachieveredundancyandcanbereplacedonline(plug),therecoverytimeofthefaultiscompletedwithinasecondinterval.Themulti-levelfault-tolerantdesignfurtherimprovestheavailabilityofthesystembasedonthehighreliabilityofasingledevice.

Asfarasenterpriseapplicationsareconcerned,itusesadvancedcomputer,networkandotherinformationtechnologiestorealizeautomaticcontroloftheproductionprocessandpaperlessofficeautomation,whichimprovestheefficiencyandlevelofproductionandmanagementoftheenterprise.Theinfrastructuresupportingenterpriseapplicationsistheenterprise'scampusnetwork.Itsworkingconditionswilldirectlyaffecttheenterprise'sofficeapplicationenvironment,businessenvironmentsuchastransaction,production,development,design,financialmanagement,partsmanagementandotherenvironments,informationretrieval,databasequery,Internetbrowsingandothernecessaryservicefacilitiestosupportthenormaloperationoftheenterprise.Thereliabilityrequirementofthenetworkistheprimaryconditiontoensurethenormaloperationoftheenterpriseapplicationenvironment.Whilethenetworkrequiresreliability,italsorequiresthenetworktohavehighavailability.Thechoiceofnetworkequipment,especiallythecorechassis-typeequipment,shouldbeabletoconfigureredundantcomponents.Thereisnosinglepointoffailureforkeycomponents.Thatistosay,componentssuchasswitchpowersupplies,fans,switchingengines,andmanagementmodulescanberedundantlybackedup.Thedamageofanypartofoneofthemwillnotaffectthenormaloperationoftheequipmentandwillnotaffectthenetworkconnection.Anotherrequirementforthereliabilityandfaulttoleranceofthenetworkequipmentisthatwhenthedamagedpartsoftheequipmentarereplaced,thereisnoneedtoshutdown,andthereisnoneedtorestartafterreplacingtheparts.Thatistosay,thereplacementofthepartscanbeoperatedonline,whichcanreducethedowntime.Tothesmallest.Ontheprincipleofdesigningenterprisecampusnetworks,itisveryimportanttoimprovetheprinciplesofhighreliabilityandhighavailabilityofthenetwork.Notonlytheequipmentcomponentsarerequiredtoberedundant,butalsothenetworklinkredundancyisrequired,whichcancombinethephysicallayer,linklayerandThethirdlayeroftechnologyisimplementedtoensurethatthenetworkcanprovideinformationaccessservicesatanytimeandanyplace.

Scalability

Thescalabilityrequirementsofnetworkdesignincludethescalabilityofswitchhardwareandtheabilityofthenetworktoimplementnewapplications.Flexiblescalabilityrequirementsforcoreswitches:Thecoreswitchesshouldhaveflexibleportexpansioncapabilitiesandmoduleexpansioncapabilitiestomeettheexpansionofnetworkscale;atthesametime,improveperformancetomeethigherperformancerequirements.Abilitytosupportnewapplications:Theproducthasthetechnicalpreparationtosupportnewapplications,andcanimplementnewapplicationsquicklyandeasily.

G-bit Ethernet

otsikko

Scaleandusers

Whendesigninganetworkplan,thefirstthingtodoistomeettheneedsofnetworkusersoftheexistingscale.Atthesametime,consideringfuturebusinessdevelopmentandscaleexpansion,thenetworkshouldbedesignedIthasflexibleexpansioncapabilitiesforuserports.Thecoreequipmentisthehuboftheentirenetwork.Theexpansionofthenumberofuserportsrequirestheadditionofequipmentintheedgeworkinggroupofthewiringcloset.Whentheedgeequipmentisadded,thenumberofportsconnectedtothecorebackboneequipmentisrequiredtoincreaseaccordingly.Therefore,thecoreequipmentshouldbeabletoincreasethenumberofmodules.Toflexiblyincreasethenumberofports.Thechassisdesignofthecoreequipmentshouldhaveastrongbackplanebandwidthandenoughloadslotcapacity.Fortheswitch,thecoreswitchingengineshouldbeabletoperformportdatapacketswitchingwithoutblockingunderthemaximumconfiguration,andtheexpansionofthemoduledoesnotaffecttheswitchingperformance.Theuseofadistributedswitchingstructureisthebestsolutiontorealizethisprinciple.Thedistributedswitchstructurerealizestheparalleldataexchangeprocessingoftheswitchesandoptimizestheperformanceofthenetwork.Thedistributedstructurecombininglocalandglobalswitchingreducesthecoreswitchingengine.pressure.Therefore,intheprincipleofdesigninglarge-scalecampusnetworks,distributedswitchesaregenerallyusedtoachieveflexiblemoduleandportexpansioncapabilities.

Security

Networksecurityisveryimportanttonetworkdesign.Reasonablenetworksecuritycontrolcaneffectivelyprotectandcontroltheinformationresourcesintheapplicationenvironment.Networkaccess,flexibleimplementationofnetworksecuritycontrolstrategies.Intheenterprisecampusnetwork,onlysystemadministratorshavethepowertooperateandcontrolkeyapplicationserversandcorenetworkequipment.Theapplicationclientonlyhastherighttoaccesssharedresources,andthenetworkshouldbeabletopreventanyillegaloperations.Itshouldbepossibletoperformpacketfilteringcontrolfunctionsbasedonprotocol,Macaddress,andIPaddressonthecampusnetworkequipment.Inthedesignoflarge-scalecampusnetworks,dividingvirtualsubnetscaneffectivelyisolatealargenumberofbroadcastsinthesubnetsontheonehand,andontheotherhandisolatethecommunicationbetweennetworksubnets,controlresourceaccessrightsandimprovenetworksecuritysex.Inthedesignofthecampusnetwork,thesecuritycontrolcapabilityofthenetworkmustbeemphasized,sothatthenetworkcanbeconnectedarbitrarily,andtheaccesstothenetworkcanbecontrolledfromthesecondandthirdlayers.

Manageability

Networkmanageabilityrequirements:anydeviceinthenetworkcanbecontrolledthroughthenetworkmanagementplatform,andnetworkequipmentstatus,faultalarms,etc.canallbemanagedthroughthenetworkmanagementTheplatformperformsmonitoring,simplifiesmanagementthroughthenetworkmanagementplatform,andimprovestheefficiencyofnetworkmanagement.

Innetworkdesign,itisessentialtochooseadvancednetworkmanagementsoftware.Networkmanagementsoftwareisusedinnetworkequipmentconfiguration,networktopologydisplay,networkequipmentstatusdisplay,networkequipmentfailureeventalarm,networktrafficstatisticsanalysisandbilling,etc.Theapplicationofnetworkmanagementsoftwarecanimprovetheefficiencyofnetworkmanagementandreducetheburdenonnetworkmanagementpersonnel.Thegoalofnetworkmanagementistoachievezeromanagement,astrategy-basedmanagementmethod,andnetworkmanagementisgloballycontrolledbythemanagementstrategyserverbyformulatingaunifiedstrategy.Theweb-basednetworkmanagementinterfaceisthedevelopmenttrendofnetworkmanagementsoftware,andtheflexibleoperationmodesimplifiestheworkofmanagementpersonnel.Inthedesignofthecampusnetworkequipmentselection,thenetworkequipmentisrequiredtosupportthestandardnetworkmanagementprotocolSNMP,whilesupportingtheRMON/RMONIIprotocol,andthecoreequipmentisrequiredtosupporttheRAP(remoteanalysisport)protocoltoimplementsufficientnetworkmanagementfunctions.Inprinciple,thedesignofthecampusnetworkshouldrequirethemanageabilityofequipment,whileadvancednetworkmanagementsoftwarecansupportnetworkmaintenance,monitoring,configurationandotherfunctions.

Standardizationoftheprotocol

Networkequipmentadoptsopentechnologyandsupportsstandardprotocols:standardprotocolsareusedtoprotectusers’investmentandimproveequipmentinteroperability.Theequipmentusedinnetworkdesignrequiresmainstreamtechnologyanddevelopedstandardprotocols,hasgoodinteroperability,andcansupportdifferentseriesofproductsofthesamemanufacturer,andseamlessinterconnectionandcommunicationbetweenproductsofdifferentmanufacturers.Ontheprincipleofdesigningthecampusnetwork,thespecialadvancedtechnologyofdifferentmanufacturers'productsmustbeused,andthestandardizationofequipmenttechnologyandprotocolmustbeemphasizedtoreduceequipmentinterconnectionproblemsandnetworkmaintenancecosts,sothatuserinvestmentcanbeeffectivelyprotected.

Itshouldbeconsideredwhethertheselectedequipmentisupgradeable.Afterthenewstandardappears,thesystemshouldbeabletoupgradetothenewstandard.Therefore,focusonthestatusofproductmanufacturersinthecorrespondingproductandtechnicalfieldsandtheirabilitytoparticipateinstandardization.

Intoday'sworld,thedevelopmentofcommunicationtechnologyandcomputertechnologyischangingwitheachpassingday.Networkdesignmustnotonlyadapttothetrendofnewtechnologydevelopment,ensuretheadvancednatureofthesystem,butalsotakeintoaccountthetechnicalmaturity,andreducetheriskscausedbyimmaturefactorsinnewtechnologiesandnewproducts.

Ratkaisu

Gigabit Ethernetin suurin etu on yhteensopivuus olemassa olevan Ethernetin kanssa.Kuten 100M-bitEthernet,GigabitEthernetusestsama kehysmuoto ja kehyskoko 10M-bittinen Ethernet,ja sama CSMA/CD-protokolla.

Asafeatureofcampusnetworkapplications,mostapplicationsarenotsensitivetodelayandbandwidth,andcanautomaticallyidentifydelaychangesthroughtheTCP/IP"slowstart"mechanism,anddynamicallyadapttothebandwidthprovidedbyTCP,Someapplicationsrequirereal-timeservicetransmissionsupportandQoSserviceguarantee.Thispartoftheapplicationaccountsforasmallproportion.Withtheaccelerationofthemodernizationofteachingmethods,thegradualpopularizationofmultimediacoursewareproductiontools,andthegradualenrichmentofmultimediacourseware,theproportionisexpectedtograduallyincrease.Themainbottleneckofreal-timeservicetransmissionoverIPnetworkisthatroutersusesoftwaretorealizerouteidentification,calculationandpacketforwarding.Duetotheslowspeedofrouteidentificationanddataforwarding,thedelayanddelayjitterarelarge,thequalityofservice(QoS)cannotbeguaranteed.Sincethesecondhalfof1997,somecompanieshavesuccessivelyintroducednewwire-speedroutingswitchesthatusehardwarededicatedcircuits(ASIC)forroutingidentification,calculation,andforwarding.Thestructureofthiswire-speedroutingswitchissimilartothatoftheL2switch.IthasboththeL3routerpacketforwardingfunctionandtheL2switchingfunction.SomemanufacturersalsoaddsomeL4applicationlayerfunctions.

ToprovideQoSonthepacket-switchedIPnetwork,theservicemustbeclassified,andtheclassificationservice(CoS)mustbeimplemented.Equipmentmanufacturersgenerallyusecongestionmanagementtoensurenetworkperformanceandprovidetherequiredbandwidthforsomespecializedservices.OneapproachistouseRED(RandomEarlyLoss)todetectandintelligentlyidentifytheinstantaneoussurgeintraffictodistinguishitfromrealnetworkcongestiontoavoidnetworkcongestion.Byidentifyingtheservicecategory(802.1P)fromtheIPv4serviceclassificationidentifier(TOS)intheIPpacketheader,thepriorityofthedataflowisdetermined,andacertainqueuepriorityalgorithmisusedtoensuretheQoScapability.Youcanalsouseanaccesscontrollist(ACL)todefinepoliciesanddeterminethepriorityofdatastreams.Withtheadvancementoftechnology,itisforeseeablethatQoScapabilitiesonhigh-speedIPnetworkswillreachasimilarlevelofFR/ATMnetworks.

Onthebasisofanalyzingandcomparingtheperformance,price,andserviceofavarietyofL2/L3/L4wire-speedroutingswitchesinthemarket,atotalof11CajunP550RroutingswitchesfromLucent(Lucent)wereselectedasthecampusNetworkbackboneswitch.Itsmaintechnologyandperformanceindicatorsare:

Takalevyn kapasiteetti 45,76 Gbps

Kytkentäkapasiteetti 22,88 Gbps

Layer2-kytkentäkapasiteetti33 000 000 pps

Layer3-kytkentäkapasiteetti18 000 000 pps

Useita L2/L3-liitäntämoduuleja

Varastetut tuulettimet, virtalähteet

OpenTrunk/VLAN-yhteentoimivuus

CoS/QoS/RSVP-tuki

Innetworkdesign,backboneswitchesareinterconnectedwitheachotherthroughGigabitEthernet.AllswitchesareequippedwithL3switchingenginetoimplementdistributedroutingstrategies,therebyreducingthepressureonL3routinganalysisandpacketforwardingofthecentralswitchandcontrollingthescopeofthebroadcastdomain.Thenetworkdesignandequipmentconfigurationcarefullyconsiderthephysicalandlogicalredundancyofequipment,linesandrouting,thefirewallsettingsandsecuritypoliciesofthenetworkcenterservergroup.

Teknologia

1000 Base-TTeknologia

Gigabit-Ethernet-kytkinlaitteiden kansallisten teknisten eritelmien julkaisemisen myötä GigabitEthernet-teknologian sovellusta on kehitetty harppauksin.

1000Base-T(GigabitEthernetimplementedonCategory5twistedpair)hasbecomeoneofthebestchoicesfornetworkmanagersduetothefollowingreasons.First,itmainlymeetstherapidlyincreasingdemandforbandwidthinexistingnetworks;secondly,inthesenetworks,emergingapplicationscontinuetoappear,andswitchesattheedgeofthenetworkarealsoincreasing.GigabitEthernetcanprotectthecompany'sexistinginvestmentsinEthernetandFastEthernetfacilities;third,itcanprovideasimple,effectiveandinexpensiveperformanceimprovementmethod,whilecontinuingtousealargenumberofexistingHorizontalcabletransmissionmedium.

1000Base-T-teknologiaperiaate

Transmissionmediaspecification

GigabitEthernetcanusetheexistingcablefacilities,sothatithasagoodperformancepriceCompare.Itcanbeusedonthenetworkinfloors,buildingsandcampusesbecauseitcansupportmultipleconnectionmediaandawiderangeofconnectiondistances.Inparticular,GigabitEthernetcanrunonthefollowingfourmedia:opticalfiber,withamaximumconnectiondistanceofatleast5kilometers;Modularfiber,withamaximumconnectiondistanceofatleast550meters;balanced,shieldedcoppercable,withamaximumconnectiondistanceofatleast25meters;Category5lines,withamaximumconnectiondistanceofatleast100meters.

TheIEEE802.3zGigabitEthernetstandardwasapprovedinJune1998.Itdefinesthreetransceiversforthreetransmissionmedia:1000Base-LX,1000Base-SXand1000Base-CX.Amongthem,1000Base-LXisusedtoinstallsingle-modeopticalfiber,1000Base-SXisusedtoinstallmulti-modeopticalfiber,and1000Base-CXisusedtobalanceandshieldcoppercables.Itcanbeusedforinterconnectionincomputerrooms.1000Base-LXtransceiverscanalsobeusedformultimodeopticalfibers,withatransmissiondistanceofatleast550meters.

GigabitEthernetLayering

Anotherspecialworkinggroup,IEEE802.3abhasdefinedthephysicallayerforrunningGigabitEthernetonthebasisofCategory5lines.TheIEEEStandardizationCommitteeapprovedthe1000Base-TstandardinJune1999.1000Base-Tcancontinuetousetheexistingcablefacilities,anditstipulatesthatthetransmissiondistanceontheCategory5linecanbeupto100meters.

Jotkut muut tärkeät 1000 Base-Tmakeitalhaisen, vaikeasti rikkoutuvan ja hyvän suorituskyvyn teknologian tekniset tiedot. Ensinnäkin se tukee EthernetMAC-yhteyttä 10/100 MbpsEthernet-tekniikan kanssa; toiseksi, monta1000/1Base-10-0,0,1-tuki0-0-0, 0Base-Tvoidaan suoraan siirtää nopean Ethernet-verkon päivitystoteutuksen kautta; kolmas, 1000Base-Tisa-korkean suorituskyvyn tekniikka, se lähettää 10 miljardia bittiä, josta hyötyy enemmän kuin yhtä uutta databittiä (biterrorrate on pienempi kuin 10-10, mikä on 100 Base-T:n bitterrorTherateon verrattavissa).

Kaapelin tekniset tiedot

1000Base-Testipulatests that datactredadcategory5balanced-kierretyillä kaapeleilla.ANSI/EIA/TIA-568-A(1995)määrittää neljän parin suorituskyvyn. )määritelty TIA/EIA-TSB-95:ssä.Category5-kaapeleiden standardi on määritelty ISO/IEC11801:1995:ssä ("Information Technology:General Cablesfor User Front-end Equipment"). Tämä ISO/IEC11801:1995:n toinen ehto määrittelee joitain muita Gigabit Ethernet -tukikaapelin suorituskykyparametreja.

Fyysinen rakenne

1000 Base-Tissuunniteltu erityisesti lähettämään dataa luokan 5 kierretyille kaapeleille. Lähetysnopeutta 1 Gbps voidaan pitää yhtä hyvin neljänä parina kierrettynä parina ja lähetysnopeudena 1 Gbps (250 Mbps).

1000Base-Tand100Base-Tusethesametransmissionclockfrequency(125MHz),butuseamorepowerfulsignaltransmissionandencoding/decodingscheme,whichcanbecomparedto100Base-TonthelinkTtransmitstwiceasmuchdata.Thefollowingisacomparisonofthesetwotechnicalspecifications:

1000 Base-T: 125 MHz × 2 bittiä = 250 Mbps

1000 Base-TX: 125MHz × 2bit-symbol = 125Mbit-symbol/s

Huomaa:125Mbits-symbol/sisequivalentto100Mbps,koska1000Base-Tusesa4B/5Benkoodaus-ennen signaalin liittämistä lähetyskaapeliin,joka 4bittitiedot muunnetaan 5-bittisiksi symboleiksi.

1000Base-Tencoding

Epäjärjestyskustannustehokkaastikäytä 4-5 tyyppistä UTP:tä, IEEE802.3abdoesnouse8B/10Bencoding,muttamäärittäälogianMAC-alakerroksen ja PHY-kerroksen kanssa.käyttöliittymä sallii dth,on ilmeinen,että jokainenCategory5UTP-pari ei saa ylittää 125Mbaud(kunCategory5UTP on62,5MHz,sen ACR on30,6dB). koodihyväksytty,eli 8B/4Quinary.Tällä tavalla,(1000/4)×(4/8)=125Mbaudvoi täyttää käytettävissä olevan kaistanleveyden rajoituksen.

Jos nelitasoista (neljäsosaa)koodausta käytetään,ylempiä vaatimuksia voidaan myös täyttää, ja se voi myös kattaa 28=256, mutta viisitasoista (neljäsosaa)koodausta voidaan käyttää neljän muun tason virheenkorjauskoodiin.

Viimeisin 1000 GigabitEthernet Alliancen Base-Twhite PaperssuositteleePAM-5-koodin käyttöä, jokainen symboli(ota yksi+2,+1,0,-1,-2)vastaa kahta numeroa Binääritietoa(neljätasoa edustaakaksibittiäkorjaavallekoodille,taiwardercodeer). tsthe4-dimensional 8-stateTrellisforwarderorrorkorjauskoodi.Näiden toteutuminen riippuu pääasiassa integroidun piirin tekniikasta ja digitaalisen signaalinkäsittelytekniikasta (DSP).

1000Base-TcansupporttheexistingFastEthernetandV.90/56Kmodemtechnologiesthathavebeentestedinpractice,therebyachievingagoodperformance-priceratio.AdvancedDSPsthatimplementsignaltransmissionandencoding/decodingtechniquesin802.3FastEthernetandV.90or56Kmodemscanalsobeusedtoimplement1000Base-T.

Kehitysedut

GigabitEthernetisanewtypeofhigh-speedlocalareanetwork,whichcanprovide1Gb/scommunicationbandwidth,andadopts10/100MEthernethasthesameCSMA/CDprotocol,frameformatandframelength,soitcanachieveasmoothandcontinuousnetworkupgradeonthebasisoftheoriginallow-speedEthernet,whichcanmaximizetheprotectionoftheuser'spreviousinvestment.

Conclusion

AsmoreandmoredesktopcomputersandworkgroupsupgradetoFastEthernet,thecentralizedbusinessofthebackboneofthenetworkwillincreasesubstantially.Inordertohandlethiskindofbusiness,allnewbackboneswitchesshouldsupportGigabitEthernetuplinks.GigabitEthernetswitchesinthebackbonenetworkcanbeusedtoconnecthightransactionrateserversandnetworksegmentswitchesforcentralizedFastEthernetworkinggroups.IftheopticalfibernetworkconnectionmodeofGigabitEthernetsolvesthehigh-speedconnectionbetweenbuildings,then1000Base-TGigabitEthernettechnologyisusedtosolvethehigh-speedconnectionbetweenfloorsandevenbetweenoffices.

Muut tyypit

StandardEthernet

Aluksi Ethernet-verkon nopeus on vain 10 Mbps, ja se käyttää useaa pääsyä törmäystunnistukseen (CSMA/CD, CarrierSenseEMultipleAccession Ethernet voi käyttää paksua koaksiaalikaapelia, ohutta koaksiaalikaapelia, suojaamatonta kierrettyä paria, suojattua kierrettyä paria ja optista kuitua ja muita lähetysvälineitä liitäntää varten, ja IEEE802.3-standardissa on muotoiltu erilaisia ​​lähetysvälineitä .Fyysisen kerroksen standardit.Näissä standardeissa etunumero ilmaisee lähetysnopeuden, yksikkö "Mbps", viimeinen numero ilmaisee verkkokaapelin yhden osan pituuden (perusyksikkö 100 m), kantaluku tarkoittaa "kantakaistaa" ja laajakaista "laajakaistaa".

·10Base-5käyttää paksua koaksiaalikaapelia, jonka halkaisija on 0,4 tuumaa ja impedanssi 50 Ω, joka tunnetaan myös paksuna Ethernet-kaapelina,verkkosegmentin maksimipituus on 500 m,kantataajuuslähetysmenetelmä,topologia onbustypei:n pääverkkoon: aksiaalikaapeli, Ethernet-kortti AUI-pistokkeella, toistin, lähetin-vastaanotin, lähetinvastaanotin, pääte jne.

·10Base-2käyttää koaksiaalikaapelia, jonka halkaisija on 0,2 tuumaa ja impedanssi 50 Ω, joka tunnetaan myös ohuena kaapelinaEthernet.Verkon enimmäispituus on 185 m, kantataajuuslähetysmenetelmä jatopologia onväylätyyppi, verkkokortti, jossa on BNC-liitin, toistin, T-liitin, pääte jne.

·10Base-Tuse-kierretty-parikaapeli,verkkosegmentin maksimipituus on 100 m,jatopologia on tähden muotoinen;10Base-T-verkon päälaitteistolaitteet sisältävät:Luokka3tai Luokka5suojaamattomatR-kortit,kierretyt parikaapelit,Bketit,4-kortit,RJ-net-4 5 pistoketta jne.

·1Base-5 eniten kierrettyä pariliitosta,verkkosegmentin enimmäispituus on 500 m ja lähetysnopeus 1 Mbps;

·10Broad-36 käyttää koaksiaalikaapelia (RG-59/UCATV),verkon enimmäisleveys on3600m ja verkkosegmentin maksimipituus1800m,joka on laajakaistainen siirtomenetelmä;

·10 Base-sulakkeetoptisen kuitulähetysmedian ja lähetysnopeus on 10 Mbps.

FastEthernet

Withthedevelopmentofthenetwork,thetraditionalstandardEthernettechnologyhasbeenunabletomeettheincreasingdemandfornetworkdatatrafficspeed.BeforeOctober1993,forLANapplicationsrequiringdatatrafficabove10Mbps,onlytheopticalfiberdistributeddatainterface(FDDI)wasavailable,butitwasaveryexpensiveLANbasedon100Mpbsopticalcable.InOctober1993,GrandJunctionlaunchedtheworld'sfirstfastEthernethubFastch10/100andnetworkinterfacecardFastNIC100,andthefastEthernettechnologywasofficiallyapplied.Subsequently,Intel,SynOptics,3COM,BayNetworksandothercompanieshavealsolaunchedtheirownfastEthernetdevices.Atthesametime,theIEEE802engineeringgroupalsoconductedresearchonvariousstandardsof100MbpsEthernet,suchas100BASE-TX,100BASE-T4,MII,repeater,fullduplexandotherstandards.InMarch1995,IEEEannouncedtheIEEE802.3u100BASE-TFastEthernetstandard(FastEthernet),andthusbegantheeraofFastEthernet.

ComparedwiththeoriginalFDDIworkingat100Mbpsbandwidth,FastEthernethasmanyadvantages.ThemostimportantthingisthatFastEthernettechnologycaneffectivelyprotecttheuser’sinvestmentintheimplementationofwiringinfrastructure.ItsupportsTheconnectionofcategory3,4,5twistedpairandopticalfibercaneffectivelyutilizetheexistingfacilities.TheshortcomingsofFastEthernetareactuallytheshortcomingsofEthernettechnology,thatis,FastEthernetisstillbasedonCSMA/CDtechnology.Whenthenetworkloadisheavy,itwillcauseadecreaseinefficiency.Ofcourse,thiscanbecompensatedbyswitchingtechnology.The100MbpsfastEthernetstandardisdividedintothreesub-categories:100BASE-TX,100BASE-FX,and100BASE-T4.

·100BASE-TX:isafastEthernettechnologythatusesCategory5data-levelunshieldedtwistedpairorshieldedtwistedpair.Itusestwopairsoftwistedpairs,onepairforsendingandonepairforreceivingdata.The4B/5Bencodingmethodisusedinthetransmission,andthesignalfrequencyis125MHz.ComplywithEIA586'sCategory5wiringstandardandIBM'sSPTCategory1wiringstandard.UsethesameRJ-45connectoras10BASE-T.Itsmaximumnetworksegmentlengthis100meters.Itsupportsfull-duplexdatatransmission.

·100BASE-FX:ItisakindoffastEthernettechnologythatusesfiberopticcable,whichcanusesingle-modeandmulti-modefiber(62.5and125um).Themaximumdistanceofmultimodefiberconnectionis550meters.Themaximumdistanceofsingle-modefiberconnectionis3000meters.The4B/5Bencodingmethodisusedinthetransmission,andthesignalfrequencyis125MHz.ItusesMIC/FDDIconnector,STconnectororSCconnector.Itsmaximumnetworksegmentlengthis150m,412m,2000morlongerto10kilometers,whichisrelatedtothetypeoffiberusedandworkingmode,anditsupportsfull-duplexdatatransmission.100BASE-FXisparticularlysuitableforapplicationsinenvironmentswithelectricalinterference,large-distanceconnections,orhigh-securityenvironments.

·100BASE-T4:ItisakindoffastEthernettechnologythatcanuse3,4,5typesofunshieldedtwistedpairorshieldedtwistedpair.100Base-T4uses4pairsoftwistedpairs,ofwhichthreepairsareusedtotransmitdataatafrequencyof33MHz,andeachpairworksinhalf-duplexmode.ThefourthpairisusedforCSMA/CDconflictdetection.The8B/6Tencodingmethodisusedinthetransmission,andthesignalfrequencyis25MHz,whichconformstotheEIA586structuredwiringstandard.ItusesthesameRJ-45connectoras10BASE-T,andthemaximumnetworksegmentlengthis100meters.

10 GigabitEthernet

10 GigabitEthernet-spesifikaatio sisältyy IEEE802.3-standardin lisästandardiinIEEE802.3ae.Iteksti päättyy IEEE802.3-protokollaan ja MAC-spesifikaatioon, joka tukee10 Gb/sTiirtosiirtoa. 10 Gigabit Ethernet-kanavaa on myös säädetty pienemmälle lähetysnopeudelle, kuten 9,584640 Gb/s (OC-192), mikä mahdollistaa 10 Gigabit Ethernet-laitteen yhteensopivuuden synkronisen optisen verkon (SONET)STS:n kanssa -192c lähetysmuoto.

·10GBASE-SRja 10GBASE-SW tukevat pääasiassa lyhytaaltoaaltoa (850nm) monimuotokuitua (MMF), ja kuituetäisyys on 2m-300m.

10GBASE-SRmainlysupports"darkfiber".Darkfiberreferstoanopticalfiberthathasnolightpropagationandisnotconnectedtoanyequipment.

10 GBASE-SW-käyttöä käytetään pääasiassa laitteiden yhdistämiseen, ja sitä käytetään etätietoliikenteeseen.

·10GBASE-LRja 10GBASE-LW tukevat pääasiassa pitkäaaltoista (1310nm)yksimuotoista kuitua (SMF), jonka kuituetäisyys on 2m–10 km (noin 32 808 jalkaa).

Kun 10GBASE-LW:tä käytetään pääasiassa laitteiden kytkemiseen,

10 GBASE-LR-tukea "darkfiber".

·10 GBASE-ER ja 10 GBASE-EW tukevat pääasiassa ultrapitkää aaltoa (1550 nm) yksimuotokuitua (SMF), jonka kuituetäisyys on 2 m–40 km (noin 131 233 jalkaa).

10 GBASE-EW:tä käytetään pääasiassa laitteiden yhdistämiseen,

10GBASE-ERkäytetään "darkfiber"-tukeen.

·10GBASE-LX4useswavelengthdivisionmultiplexingtechnologytosendsignalsatfourtimestheopticalwavelengthonasinglepairofopticalcables.Thesystemrunsunder1310nmmulti-modeorsingle-modedarkfibermode.Thedesigngoalofthissystemisforthemulti-modefibermodefrom2mto300morthesingle-modefibermodefrom2mto10km.

△Ethernet-yhteys

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