【英文标准名称】:Fibreopticaccesstoend-user—AguidelinetobuildingofFTTXfibreopticnetwork
【原文标准名称】:用户终端的纤维光学通路.FTTX纤维光学网络的建设指南
【标准号】:BSPDCLC/TR50510-2007
【标准状态】:现行
【国别】:英国
【发布日期】:2007-11-30
【实施或试行日期】:2007-11-30
【发布单位】:英国标准学会(GB-BSI)
【起草单位】:
【标准类型】:()
【标准水平】:()
【中文主题词】:
【英文主题词】:
【摘要】:ThisTechnicalReportdescribestheFTTX-network.Asaguidelineotherpartsofthefibreopticinfrastructurearegiveninthisclause.Firstsomebasics:sound,pictures,voice,datacarriedbynetworksaredigitaldataexpressedintermsofbit,bytesandtheirmultiples(kilo(k),mega(M),giga(G),tera(T)).Abit(binarydigit)isthesmallestdigitalunitandhasonlytwovalues:0or1.Abyteincludes8bitsanddefinesthesizeofadatafile.Transmissioncapacityofnetworksandterminalsisnotexpressedbyusingbytes,butusingbitpersecond(bps).Whenadatafileistransferredinanetworktwosupplementarybitsarenecessary.Itmeansthat10bitsarerequiredfor1byte.InthecaseofaVDSLsubscriberwith10Mbit/s,whowantstouploadapdfdatafile,theWebproviderindicatesforinstancethefollowingsize:20Megabytes.Itshouldthentake20s.However,foranyMbit/ssubscriptionthefactisthattherealfinaldataflowisaboutaquarterofthenotifieddataflow,becausethedataflowissharedbetweensubscribersanditsqualitydependsontheactivityoftheothersubscribers.Itmeansthatthe20Megabytesdatafilewillneed1min20stobeuploaded.Forinstancea15Mbit/sADSLsystemgivesonly1Mbit/sforuploading.ThefollowingtablegivessomefurtherexamplesoftransmissiontimesforuploadingaqualityDVD-movie,ifthereisnodataflowsharing.Wedonotknowthenewtoolsthatwillbecreatedbytherealhighbitratenetworks.Newapplications(notinventedtoday)willappearandapplicationsoriginallydedicatedtoprofessionalswillbeextendedtoallinasimilarwayasithappenedwiththemobilephone.Itisimportanttodefinethemeaningof?low,mediumandhighbitratetransmission?.Onepossibleclassificationispresentlythefollowing:?lowbitratetransmission:upto1Mbit/s?mediumbitratetransmission:1upto10Mbit/s?highbitratetransmission:10upto100Mbit/sandmore.
【中国标准分类号】:M33
【国际标准分类号】:33_180_99
【页数】:94P.;A4
【正文语种】:英语