电子信息工程外文翻译综合布线的未来适用于毕业论文外文翻译+中英文对照Word格式文档下载.docx

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外文文献及译文

文献、资料题目:

Thefutureofstructurecablingsystems

文献、资料来源:

CablingInstallation&

Maintenance

Magazine

文献、资料发表（出版）日期:

2005.12.1

院（部）:

信息与电气工程学院

专业:

电子信息工程

班级:

姓名:

学号:

指导教师:

翻译日期:

2012.4.1

外文文献：

Thefutureofstructuredcablingsystems

Whichtechnologieswillmeetspeedanddata-transmissionrequirementsinthefuture?

Todiscussthefutureofstructuredcablingsystems,weshouldspendamomentlookingatthepastandpresentpractices.Beforeearly1984,communicationswiringsystems,astheywerethencalled,werenottopicsofmuchdiscussion.Data-transportspeedswerecomparativelyslow,transmissionbandwidthrequirementswereminimal,and"

others"

providedthedesignandinstallationofthecablingsystem.Thetelephonecompaniestookcareoftheinstallationandmaintenanceofthetelephoneservice.Whendataservicesbecamedistributed,thecablingsystemwasvendor-specific,andtheinstallationandmaintenanceofthecableplantwasprovidedbytheequipmentvendors,orspecializedindependentcontractors.

InJanuary1984,thecourtsintheU.S.madeseveralimportantrulingsthatchangedthewaytelecommunicationswasprovidedanddistributed.Outsideoftraditionalsuppliersofcablingsystems,notmuchwasunderstoodaboutthecablingrequirementsforcommunicationstransport.Theproliferationofmediaandconnectorinterfaces,alackofstandardtransmissionspecifications,andtheintroductionofcablingschemesbyvendorsaddedtotheuser'

sconfusion.Bringingordertotheconfusionandcreatinggenericcablingsystemsdemandedthecreationofastandardsbodywhoseoutputwouldfocusoncommercialbuildingsandcommunicationscabling.

Sincetheintroductionofthefirstcablingstandardin1991bytheTelecommunicationsIndustryAssociation/ElectronicIndustryAlliance（TIA/EIA）,thatsamegrouphasissuedaseriesofstandardsandspecificationsregardingmostaspectsofthestructuredcablingsystems.Thesestandardshaveprovidedguidancerelatedtoevolvinghigh-speedinformationtransportsystems.Thevastmajorityofpastandpresentdigitalcommunications,usedinthecommercialworld,hasbeentransportedonunshieldedtwisted-pair（UTP）cablingsystems.UTPbecamethemediumofchoicebecauseitwaseconomical,perfectlyadequatefortheapplications,andcomparativelyeasytoinstallversusotheravailablemediatypes.

Withadvancementsinnetworkspeeds,newtransmissionspecificationsforUTPcableandconnectinghardwarehavebeenpromotedbymanufacturersandeventuallyendorsedbythestandardscommunity.In1991,thehighestratedbandwidthoverUTPwas16MHz;

wearenowfacedwithtransportspeedsdemandingtransmissionbandwidthsof250MHzandbeyond.ManufacturershaverisentothechallengeandprovidedUTPcomponentsfortoday'

stransmissionrequirementsinexcessof600MHz.Whatmediaandconnectorswillbeavailablethatwillbeeconomicallyfeasibleatbandwidthsof1GMHz?

AtwhatpointdoesUTPbecomelesseasytouseandlesseconomicalthanothermedia?

Futuredirections

Asfaraswecanseeintothefuture,commercialinformationtransferwillconsistofbothlow-speedandhigh-speedrequirements.Applicationssuchasvoice,buildingautomationsystems,alarms,andsecuritysystemswillstilluselowbandwidths.Voiceinformationmaychangefromcentralofficeexchangedeliverytointelligentperipheral,butbandwidthrequirementswon'

tincreasebyalargeamount.Thedatapackets,withwhichthevoicepacketsride,willincreasebandwidthrequirements.Therequirementstotransportlargeamountsofinformationinshorterandshorterperiodsoftimearechanging,andwillcontinuetochange.Applicationssuchasgraphicaldata（bothschematicandpictorial）,scientificmodeling,desktopvideoconferencing,multi-tieredrelationaldatabasesandotherdata-intensiveinformationwilldriveupthebandwidthrequirements.

Ifhistoryisanypredictorofthefuture,wewillseeinformationtransferspeedsincreaseatleastoneorderofmagnitudeperdecade.Wehaveseenlocalareanetworkspeeds,onUTP,increasefrom10Mb/sinthemid1980sto100Mb/sinthemid1990sthento1Gb/sinthelate1990s.Today,standardsarebeingwrittenfor10Gb/s.Wherewillwebein2010or2020?

Microsoft'

sBillGatesisquotedassaying,"

Wewillhaveinfinitebandwidthinadecade'

stime."

LawrenceBerkeleyLaboratory（Berkeley,CA）hasprojecteditsthroughputneedsfor2020tobe40Gb/s.Whatwillbeitsmediaofchoice:

UTP,coaxial,shieldedtwisted-pair,opticalfiber,orwirelesstechnology?

Thetwomajorpropertiesrequiredforanycablingsystemtobethesystemofchoiceareitsperformanceanditsrelativeeconomics（whichincludeeaseofinstallation）.Undoubtedly,fiberandshieldedtwisted-pair（STP）systemsarequiterobustandprovidegreatersignal