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1、新的无线局域网标准计算机专业英语词汇指与计算机硬件、软件、网络等多方面有关的英语词汇，主要包括硬件基础、计算机系统维护、计算机网络基础、软件、程序设计语言、计算机网络技术、IT职场英语等词汇。下面是小编为您收集整理的新的无线局域网标准，供大家参考!新的无线局域网标准WithportablecomputersandwirelessLANs,userscanenjoygreaterproductivitywhileawayfromtheirdesks,whethertheyareinconferencerooms,publicareasorrem
2、oteoffices.Untilrecently,however,wirelessLANsweretooslowformostenterpriseapplications.basedontheIEEE802.11standdrd,theyranat1Mto2Mbit/sec.Nowanewhigh-rateextensiontothestandard,802.11b,letswirelessnetworkssupportdataratesto11Mbit/sec.Ratifiedin1997,theoriginal802.11standard
3、unitedthewirelessindusturybydefiningalow-levelprotocolarchitecturethatworkedwithconventionalupper-layerenterpriseprotocolstacks.Also,802.11maintainedcompatibilitywiththethreemostpopularradiotransmissiontypes:directsequencespreadspectrum,frequency-hoppingspreadspectrum,andin
4、frared.Essentially,thisnewarchitectureaddedintelligenceatthemediumaccesscontrol(MAC)layer2andatthephysical(PHY)layer1,fosteingcooperationbetweenthetwolayersinperformingthecriticaltasksinvolvedwithinitiatingandmaintainingwirelesscommuni-cations.Forinstance,toensurereliabilit
5、yofthewirelesslink,MACandPHYworktogethertodetermineifaclearpathexistsbeforetheystartatransmission.Duringtransmission,theyemployspecialcollision-avoidanceandarrival-acknowledgmenttechniquesthatarenotrequiredinwiredethernetLANs.Inseptember1999,theIEEEapprovedanewdesignation,k
6、nownas802.11.intendedtoretaintheerror-correction，security,powermanagementandotheradvantagesoftheoriginal,akeyingredient-athchniqueforincreasingbandwidthto11Mbit/sec.Calledcomplementarycodekeying(CCK)thetechniqueworksonlyinconjunctionwiththeDSSStechnologysprcifiedintheorigin
7、alstandard.itdoesnetworkwithfrequency-hoppingorinfraredtransmissions.WhatCCKdoesisapplysophisticatedmathematicalformulastotheDSSScodes,apermittingthecodetorepresentagreatervolumeofinformitterisnowabletosendmultiplebitsofinformationwitheachDSSScode,enoughtomakepossiblethe11M
8、bit/secintheoriginalstandard.The802.11bstandardbenefitsusersbydeliveringwirelesset
