有关固网短讯服务的技术标准

FordiscussiononlyTSACPaperNo.19/2003TELECOMMUNICATIONSSTANDARDSADVISORYCOMMITTEETechnicalStandardforFixedLineShortMessageService(FLSMS)有關固網短訊服務的技術標準IntroductionShortMessageService(SMS)hasbeenwidelymadeavailableondigitalmobilenetworksnowadays.ThemobileSMSprovidesamechanismfortransmittingshortmessagestoandfrommobilephones.ThepotentialapplicationsofSMS(suchasperson-to-personchatting,receptionofe-mailande-commerce)haveattractedfixednetworkoperatorsinsomecountriestoprovidesimilarservicestotheirsubscribers.FixedLineSMS(FLSMS)enablestheoperatorstoofferfixedlinetelephoneuserstheabilitytosendandreceivetextmessages.Thispapergivesanoverviewofthetechnologyandstandardsdevelopmentoftheservice.PrincipleofFLSMS2.FLSMSisanewvalue-addedserviceofferedtofixedlineuserstosendandreceivetextmessagestoandfromotherfixedlinetelephones,mobilephones,faxmachines,e-mailboxesandothertelephonydevices.Thesending/receptionofthetextmessagesfunctionsthesamewayaswithmobileSMS.FLSMSmessagesaretransportedviaaShortMessageServiceCentre(SMSCentre)whichstoresandforwardsthemessagestothereceivingFLSMStelephonethroughanormalvoicechanneloffixedtelecommunicationsnetworksafterthenormalcallsetup.3.ThegeneralprinciplefortransferofanFLSMSmessageisgiveninFigure1.Toestablishacircuit-switchedconnectiontotheSMSCentre,thesendingFLSMStelephoneseizesthelineanddialsthenumberoftheSMSCenterusingpulseortonediallingmethod.AfterthecallhasbeenansweredbytheSMSCentre,theconnectionisreadyandtheSMSCentreinitiatesthedatatransferbysendingtheappropriatedatalinklayermessage.AllinformationbetweentheFLSMStelephoneandtheSMScentreistransmittedinthevoicebandusingfrequencyshiftkeysignalling.TSACPaperNo.19/2003June20031FordiscussiononlyTSACPaperNo.19/2003Figure1:ShortMessagetransfer-GeneralPrinciple4.ForfixedlineuserstoreceiveSMSmessagesfromotherFLSMSormobileusers,FLSMStelephonesetsshouldbeusedtoreceiveanddisplaythemessages.AfterthereceivingFLSMStelephoneanswersthecallfromtheSMScentre,thedatalinkisestablishedinthesamewayasdescribedinparagraph3above.However,manyfixedtelephonesdonotsupporttheFLSMSatpresent.TodelivertextmessagestosubscriberswithouttheFLSMS-enableddevices,someoverseasoperatorssendthemessagesasvoicemailswiththeaidoftext-to-speechsystems.StandardforFLSMS5.Overthepasttwoyears,anumberoffixednetworkoperatorshavedeployedorplannedtoimplementFLSMSinvariouscountriessuchasAustralia,Belgium,China,Germany,Italy,Malaysia,SingaporeandSpain.Currently,implementationoftheFLSMSismostlywithinthenetworksofindividualoperators.Sendingorreceivingmessagesacrossmobileandfixednetworksofdifferentoperatorsrequiresinteroperabilityagreementsamongtheoperatorsconcerned.Withtheconvergenceofthefixedandmobileservices,itislikelythatinteroperableFLSMSwillbeavailablesooninmanycountries.TSACPaperNo.19/2003June20032FordiscussiononlyTSACPaperNo.19/20036.Sofar,theInternationalTelecommunicationUnion(ITU)hasnotyetdevelopedaninternationalstandardforFLSMS.GivenSMSisoneoftheservicesdefinedintheEuropeanGSM/PCSstandards,implementationofFLSMSbyoperatorsaroundtheworldispredominantlybasedonthestandardsdevelopedbytheEuropeanTelecommunicationsStandardsInstitute(ETSI).7.ETSIissueditsfirststandardES2019121onFLSMSinJanuary2002andissuedlaterinAugust2002anotherdocumentES1039122makingcorrectionstoitsES201912.TheETSIstandardES201912specifiestwoprotocolstoprovidetheSMSoverPSTN/ISDN.Protocol1ensuresfullcompliancewiththeGSMSMSservicewhileProtocol2specificallyfocusesontheresidentialfixednetworkenvironment.Bothprotocolsoffertheopportunitytoexchangeshortmessageswithothernetworks.8.LiketheGSMSMS,FLSMSmessagesbasedonProtocol1oftheETSIstandardhasamaximumlengthof160alphanumericcharacters.However,notmorethan70ChinesecharacterscanbetransmittedinanFLSMSmessageduetotheneedtousemorebitsfortheencoding.Withitsoptimisationunderthefixednetworkenvironment,Protocol2compliantequipmentcanhandlemuchlongermessages.ThereismarketavailabilityofFLSMSdesktoptelephonesandcordlessphones.Mostofthesephonescanbeprogrammedtocomplywitheitheroneprotocolbeforeproductdeliverybymanufacturers.InterworkingbetweentheFLSMStelephonesandSMScentrerequirestheuseofsameProtocol.9.FLSMShasbeenmadeavailableonmainlandChinasincelate2001.ThestandardsusedaredevelopedbyChinaTelecomincollaborationwiththemajorequipmentvendors,suchasZTECorporationandAlcatelShanghaiBell.Recently,itisreportedthattheMinistryofInformationIndustry(MII)ofChinahasadoptedtheChinaTelecom’sFLSMSstandardsasIndustrystandardsYD/T1248.1-20033andYD/T1248.2-20034.Thedetailsofthestandard1ETSIstandardES201912AccessandTerminal(AT);ShortMessageService(SMS)forPSTN/ISDN;ShortMessageCommunicationbetweenafixednetworkShortMessageTerminalEquipmentandaShortMessageServiceCentre.2ETSIstandardES201912AccessandTerminal(AT);ShortMessageService(SMS)forPSTN/ISDN;ShortMessageCommunicationbetweenafixednetworkShortMessageTerminalEquipmentandaShortMessageServiceCentre.(CorrectionstoES201912V.1.1.1)3YD/T1248.1-2003固定电话网短消息业务第1部分：短消息终端侧技术要求和测试方法4YD/T1248.2-2003固定电话网短消息业务第2部分：短消息终端和短消息中心之间TSACPaperNo.19/2003June20033FordiscussiononlyTSACPaperNo.19/200