《计算机专业英语》课件第6章

UNIT6

TOPICS

TEXTComputerNetworkandInternet

EXERCISES

SUPPLEMENTARYCommonlyUsedComputerNetworkCONVERSATIONBargainingSkills

WRITINGHowtoWriteaLostandFoundNoticeTOPICS

Whatisacomputernetwork?

Whendidthefirstcomputernetworkarise?

WhatistheInternet?

WhatistheWorldWideWeb?

WhatdidtheInternetbringtous?

Bargainingskills.

HowtowriteaLostandFoundNotice?

Simplyput,acomputernetworkisacollectionofautonomouscomputers.Ifyouthinkaboutcomputernetwork,thenyoushouldconsiderthefactthatitsimplemeansvariouscomputersconnectedtoeachotherwhichshouldfacilitatesharingofresources.TEXT

ComputerNetworkandInternet

Computernetworksareoftenclassifiedaslocalareanetwork(LAN),wideareanetwork(WAN),metropolitanareanetwork(MAN),WirelessNetworksandInternetworks.

TheInternetisagiantnetworkofcomputerslocatedallovertheworldthatcommunicatewitheachother.

TheInternetisaninternationalcollectionofcomputernetworksthatallunderstandastandardsystemofaddressesandcommands,connectedtogetherthroughbackbonesystems.Itwasstartedin1969,whentheU.S.DepartmentofDefenseestablishedanationwidenetworktoconnectahandfulofuniversitiesand

contractors.Theoriginalideawastoincreasecomputingcapacitythatcouldbesharedbyusersinmanylocationsandtofindoutwhatitwouldtakeforcomputernetworkstosurviveanuclearwarorotherdisasterbyprovidingmultiplepathsbetweenusers.PeopleontheARPANET(asthisnationwidenetworkwasoriginallycalled)quicklydiscoveredthattheycouldexchangemessagesandconductelectronic“conferences”withdistantcolleaguesforpurposesthathadnothingtodowiththemilitaryindustrialcomplex.Ifsomebodyelsehadsomethinginterestingstoredontheircomputer,itwasasimplemattertoobtainacopy(assumingtheownerdidnotprotectit).

Overtheyears,additionalnetworksjoinedwhichaddedaccesstomoreandmorecomputers.Thefirstinternationalconnections,toNorwayandEngland,wereaddedin1973.TodaythousandsofnetworksandmillionsofcomputersareconnectedtotheInternet.Itisgrowingsoquicklythatnobodycansayexactlyhowmanyusers“OntheNet”.

TheInternetisthelargestrepositoryofinformationwhichcanprovideverylargenetworkresources.Thenetworkresourcescanbedividedintonetworkfacilitiesresourcesandnetwork

informationresources.Thenetworkfacilitiesresourcesprovideustheabilityofremotecomputationandcommunication.Thenetworkinformationresourcesprovideusallkindsofinformationservices,suchasscience,education,business,history,law,art,andentertainment,etc.

ThegoalofyouruseoftheInternetisexchangingmessagesorobtaininginformation.WhatyouneedtoknowisthatyoucanexchangemessagewithothercomputersontheInternetanduseyourcomputerasaremote

terminalondistantcomputers.Buttheinternaldetailsofthelinkarelessimportant,aslongasitworks.Ifyouconnectcomputerstogetheronanetwork,eachcomputermusthaveauniqueaddress,whichcouldbeeitherawordoranumber.Forexample,theaddressofSam’scomputercouldbeSam,oranumber.

TheInternetisahugeinterconnectedsystem,butitusesjustahandfulofmethodtomovedataaround.UntiltherecentexplosionofpublicinterestintheInternet,thevastmajorityofthecomputersontheNetusetheUnixoperatingsystem.Asaresult,thestandardUnixcommandsforcertainInternetserviceshaveenteredtheonlinecommunity’slanguagesasbothnounsandverbstodescribetheservicesthemselves.SomeoftheservicesthattheInternetcanprovideare:Mail,Remoteuseofanothercomputer(Telnet),FileTransferProtocol(FTP),News,andLiveconversation.

Themostcommonlyusednetworkserviceiselectronicmail(E-mail),orsimplyasmail.Mailpermitsnetworkuserstosendtextualmessagestoeachother.Computersandnetworkshandledeliveringthemail,sothatcommunicatingmailusersdonothavetohandledetailsofdelivery,anddonothavetobepresentatthesametimeorplace.

Presently,auserwithanaccountonanyInternetmachinecanestablishaliveconnectiontoanyothermachineontheNetfromtheterminalinhisofficeorlaboratory.ItisonlynecessarytousetheUnixcommandthatsetsuparemoteterminalconnection(Telnet),followedbytheaddressofthedistantmachine.BeforeyoucanusetheInternet,youmustchooseawaytomovedatabetweentheInternetandyourPC.Thislinkmaybeahigh-speeddatacommunicationcircuit,alocalareanetwork(LAN),atelephonelineoraradiochannel.Mostlikely,youwilluseaModemattachedtoyourtelephonelinetotalktotheInternet.Naturally,thequalityofyourInternetconnectionandservice,likemanyotherthingsinlife,isdictatedbytheamountofmoneythatyouarewillingtospend.

Thesimplestwaytoaccessafileonanotherhostistocopyitacrossthenetworktoyourlocalhost.FTPcandothis.

Althoughalltheseservicescanwellsatisfytheneedsoftheusersforinformationexchange,adefiniterequirementisneededfortheusers.Notonlyshouldtheusersknowwheretheresourceslocates,butalsoheshouldknowsomeoperatingcommandsconcernedtoeasethesearchingburdenoftheusers,recentlysomeconvenientsearchingtoolsappears,suchasWWW.

WWW(WorldWideWeb)isanetworkedhypertextprotocolanduserinterface.ItprovidesaccesstomultipleservicesanddocumentslikeGopherdoes,butismoreambitiousinitsmethod.AjumptootherInternetservicecanbetriggeredbyamouseclickona“hotlink”word,image,oriconontheWebpage.

WWWisthemostpopularpartoftheInternetbyfar.OnceyouspendtimeontheWeb,youwillbegintofeellikethereisnolimittowhatyoucandiscover.TheWeballowsrichanddiversecommunicationbydisplayingtext,graphics,animation,photos,soundandvideo.

Sojustwhatisthismiraculouscreation?TheWebphysicallyconsistsofyourpersonalcomputer,webbrowsersoftware,aconnectiontoanInternetserviceprovider,computerscalledserversthathostdigitaldataandroutersandswitchestodirecttheflowofinformation.

AsmoreandmoresystemsjointheInternet,andasmoreandmoreformsofinformationcanbeconvertedtodigitalform,theamountofstuffavailabletoInternetuserscontinuestogrow.Atsomepointsverysoonafterthenationwide(andlaterworldwide)Internetstartedtogrow,peoplebegantotreattheNetasacommunity,withitsowntraditionandcustoms.Forexample,somebodywouldaskaquestioninaconference,andacompletestrangerwouldsendbackananswer.Afterthesamequestionwererepeatedseveraltimebypeoplewhohadn’tseentheoriginalanswers,somebodyelsegatheredlistof“frequentlyaskedquestions”andplaceditwherenewcomerscouldfindit.

SowecansaythattheInternetisyourPC’swindowtotherestoftheworld.1.Backbone(a) Amultitasking,multi-usercomputeroperatingsystemoriginallydevelopedin1969byagroupofAT&TemployeesatBellLabs.EXERCISES2．ARPANET(b)AnetworkprotocolusedontheInternetorlocalareanetworkstoprovideabidirectionalinteractivetext-orientedcommunicationsfacilityusingavirtualterminalconnection.3．Telnet

(c)Thepartofacommunicationnetworkthatcarriestheheaviesttraffic.4．Unix

(d)Itwastheworld’sfirstoperationalpacketswitchingnetworkandthecorenetworkofasetthatcametocomposetheglobalInternet.5.RemoteTerminal

(e)Aterminalconnectedtoacomputerbyadatalink.Ⅱ. ArethefollowingstatementsTrue(T)orFalse(F)?

1．()Acomputernetworkisacollectionofautonomouscomputers.

2．()Developmentofthenetworkbeganin1950s.

3．()TheInternetisagiantnetworkofcomputerslocatedallovertheworldthatcommunicatewitheachother.

4．()ThefirstnetworkintheworldisInternet.

5．()Thefirstinternationalconnections,toNorwayandEngland,wereaddedin1973.

6．()FTPisthemostpopularpartoftheInternetbyfar.

7．()ThemostcommonlyusednetworkserviceiselectronicTelnet.

8．()FTPcancopyafileonanotherhosttoyourlocalhostacrossthenetwork.

9．()Computersandnetworkshandledeliveringthemail,sothatcommunicatingmailusersdonothavetohandledetailsofdelivery.

10．()LiveconversationisaservicethattheInternetcannotprovide.Ⅲ.TranslatethefollowingwordsandphrasesintoChinese.Ⅳ.TranslatethefollowingChinesestatementsintoEnglish.

1．万维网是一个基于超文本的系统，可用于查询和访问互联网资源。

2．我认为您的调制解调器现在已经无法使用了。

3．在当今，互联网的应用无处不在，我们的工作和生活都离不开它。

4．电子邮件是一种便捷又经济的发送信息的方式。

5．互联网上的信息都是以多媒体文件的形式显示出来的。

Ⅴ. Fillineachoftheblankswithoneofthefollowingwordsor

phrases.

equipoverallservicedatasourcesrouter

associatewithconnectwirelesscorporationprocess

Computernetworkingdevicesareanytypesofdevicesthatare

acomputernetworkandaidinthe

ofmanagingdata.Alsoknownasnetworkequipmentorinterworkingunits,thecomputernetworkingdevicemaybesometypeofhardwareequipmentora

thataidsintheprocessingofdatainsomecapacity.Anytypeofnetwork,rangingfromasimplehomenetworktoawideareanetwork(WAN)utilizedbyalarge

willmakeuseofvariousnetworkingdevices.

Oneofthemorebasicexamplesofacomputernetworkingdeviceisthe

.Thistypeofdevicemakesitpossibletoconnectwith

andshareinformationovertheapplicationsusedwithinthe

networkstructure.Oneofthemorecommonexamplesofarouterisadualrouterusedinmanyhomenetworksthatis

directlytothemastercomputerthatservesastheserverforthatnetwork,andalsois

toprovidea

connectiontoothercomputersinthehome.

Youhaveprobablyheardofnetworksandnetworking,andyoumayevenbeusingonerightnow,whatexactlyisacomputernetwork?Andwhywouldsomeonewanttosetoneuporbepartofone?SUPPLEMENTARY

CommonlyUsedComputerNetwork

WhatisaComputerNetwork?

Anetworkisbasicallyasetoftwoormorearticlesthatarelinkedsothecomputerscanshareresources,suchasprinters,software,andinternetconnections.Networkedcomputerscanalsosharefileswithouthavingtotransferdatausingadiskordatakey.Andusersofnetworkedcomputerscanalsocommunicateelectronicallywithoutuseoftheinternet.

Computerswithinanetworkcanbelinkedseveralways:cables,telephonelines,radiowaves,satellites,orinfraredbeams.Therearealsothreebasictypesofnetworks:LocalAreaNetwork(LAN),MetropolitanAreaNetwork(MAN),andWideAreaNetwork(WAN).

LocalAreaNetworks

ALocalAreaNetwork(LAN)isbasicallyasmallernetworkthat’sconfinedtoarelativelysmallgeographicarea.LANcomputersarerarelymorethanamileapart.ExamplesofcommonLANsarenetworkedcomputerswithinawritinglab,school,orbuilding.WithinaLANnetwork,onecomputeristhefileserver.Thismeansthatitstoresallsoftwarethatcontrolsthenetwork,anditalsostoresthesoftwarethatcanbesharedamongcomputersinthenetwork.ThefileserveristheheartoftheLAN.

Thecomputersattachedtothefileserverarecalledworkstations.Workstationscanbelesspowerfulthanthefileserverbecausetheydon’thavetostoreasmanyfilesandapplicationsasthefileserver,andtheyarenotalwaysonandworkingtokeepthenetworkupandrunning.However,workstationsmayalsohaveadditionalsoftwarestoredontheirharddrives.MostLANsareconnectedusingcables.

MetropolitanAreaNetworks

AMetropolitanAreaNetwork(MAN)connect2ormoreLANstogetherbutdoesnotspanoutsidetheboundariesofacity,town,ormetropolitanarea.WithinthistypeofnetworkisalsotheCampusAreaNetwork(CAN),whichisgenerallysmallerthanaMAN,connectingLANswithinalimitedfunctionalarea,likeacollegecampus,militarybase,orindustrialcomplex.

WideAreaNetworks

WideAreaNetworksconnectlargergeographicareas.Often,smallerLANsareinterconnectedtoformalargeWAN.Forinstance,anofficeLANinLosAngelesmaybeconnectedtoofficeLANsforthesamecompanyinNewYork,Toronto,Paris,andLondontoformaWANspanningthewholecompany.TheindividualofficesarenolongerpartofindividualLANs,theyareinsteadpartofaworldwideWAN.

Theconnectionofthistypeofnetworkiscomplicated.WANsarenormallyconnectedusingmultiplexersconnectlocalandmetropolitannetworkstoglobalcommunicationsnetworksliketheInternet.议 价 的 技 巧议价即讨价还价，在日常生活中，讨价还价是人人都会遇到的问题。怎样议价效果才最好呢？当对方报价后，如何说服对方提供更优惠的价格呢？议价时需注意以下几点原则：CONVERSATION

BargainingSkills

1.漫不经心，声东击西当你看好某商品时，不要急着问价，先随便问一下其他商品的价格，表现出很随意的样子，然后突然问你要的东西的价格。店主通常不及防范，报出较低的价格。切忌表露出对你想要的那件商品的热情，善于察颜观色的店主会漫天起价。

2.以理服人，见好就收因讨价还价是伴随着价格评议进行的，故应尊重对方。议价应有理有据，切勿不给出充分理由而强压对方报价，使议价陷入僵局。如对方同意降价，达到自己心里价位或接近心理价位即可，不易强求，应保持平和的心态。

3.揣摩心理，掌握次数如遇到漫天要价者，应不动声色，揣摩对方心理。还价时，先压价至自己的心理价位并给出原因，再观察对方反应，逐步提价。提价时应注意尺度，可观察对方态度，随机调整提价额度。

4.评头论足，欲擒故纵试着用最快的速度列举出该货品的缺点，一般的顺序是式样、颜色、质地、做工，从而达到减价的目的。对方若不肯减价，这时即使你真的喜欢这件商品，也要当做不在意，转身就走，迫使对方减价。ExampleDialogue1

A:Hi,howmuchdoyouwantforthis?

B:150yuan.

A:What?Don’tyoutrytoripmeoff!Iknowwhatthisiscost,40yuan,tops.

B:Noway!Itcostmemorethanthat,120!

A:Comeon!Ifyoudon’tgiveabetterprice,Iwon’tbuythisfromyou.

B:110.Takeitorleaveit.

A:I’llgiveyou55.

B:Ican’tdothat.Ihavetomakealiving.Giveme100andit’syours.

A:That’sstillmuchtooexpensive.(Startingtowalkaway)

B:Wait,wait!Ok,85,finalprice.

A:Ifthat’sthelowestyou’rewillingtogo.I’mleaving.I’llpay65,finaloffer.

B:Youdriveahardbargain.I’mlosingmoneyonthis,butalright.I’llletyouhaveitfor65.

A:Thanksalot.Dialogue2Goodafternoon.CanIhelpyou?

B:Ineedadinetteset.

A:How’sthisone?

B:Looksallright.Howmuchdoyousellit?

A:850dollars.

B:Thisisoutofmypricerange.

A:What’syourgeneralpricerange?

B:Around300dollars.

A:Isthisoneallright?Itcosts380dollars.

B:Itsuitsme.Doesthepriceincludedeliveryandinstallationcharge?

A:Yes,ofcourse.

B:Isthepricenegotiable?

A:Iamsosorry.Nobargaining.

B:Comeon,givemeadiscount.Ifyoudon’tgivemeabetterprice,Iwon’tbuythis.

A:Allright,I’llgiveittoyoufor350dollars.

B:OK.Thankyousomuch.I’lltakethisone.Practice

ImaginethatyouwanttobuyaT-shirtandyourpartneristheseller.Youhopethesellergiveyouadiscount.Practicebargainingskillswiththegivenpoints:

Quotetheprice.

Dissentfromthepricewithyourreasons.

Askforadiscount.

Telltheselleryourbottomline.

Makeanagreement.Tips讨价还价常用语

1．Don’ttrytoripmeoff.Iknowwhatthiscost.别想宰我，我识货。

2．Canyougivemealittledealonthis?这件东西能卖得便宜一点吗？

3．Canyougivemethisforcheaper?能便宜一点给我吗？

4．Isthereanydiscountonbulkpurchases?我多买些能打折吗？

5．Givemeareductioninprice,please.给我打个折吧。

6．Howmuchdoyouwantforthis?这件东西你想卖多少钱？

7．Ifyoudon’tgivemeabetterprice,Iwon’tbuythis.如果价格不更优惠些，我是不会买的。

8．Icangetthischeaperatotherplaces.这件东西我在别的地方可以买到更便宜的。

9．What’sthelowestyou’rewillingtogo?最低你能出什么价？

10．Comeon,givemeabreakonthis.别这样，你就让点儿价吧。

11．Couldyougivemeadiscount?能给我个折扣吗？

12．Aretheseclothesonsale?这些衣服打特价吗？

13．Isthepricenegotiable?这个价钱可以商量吗？

14．Howaboutbuyoneandgetonefree?买一送一怎么样？

15．Canyougivemeabetterdeal?可以给我更好的价钱吗？

16．I’dbuyitrightawayifitwerecheaper.便宜一点的话我马上买。

17．Thepriceisbeyondmybudget.这个价钱超出我的预算了。

18．I’llgive500dollarsforit.五百块我就买。

19．That’ssteep,isn’tit?这个价钱太离谱了吧？

20．It’stooexpensive.Ican’taffordit.太贵了，我买不起。在英语中，寻物启事及失物招领都可以直接译成LostandFound，并没有严格的区分。按照字面上的意思，寻物启事可对应Lost，失物招领可对应Found。WRITING

HowtoWriteaLostandFoundNotice

怎样写寻物启事及失物招领

1.寻物启事(Lost)寻物启事一般包括以下几项内容。

(1)标题。寻物启事的标题可以有两种构成格式：第一，由文种名称和缘故构成。如“寻物启事”。第二，由文种名和具体丢失物名构成。如“寻书启事”、“寻自行车启事”。

(2)正文。寻物启事的正文一般由以下几项内容构成：其一，写明丢失物的名称、外观、规格、数量、品牌等，同时要写明丢失的原因、时间和具体地点。其二，交代清楚拾物者送还的具体方式，或注明发文者的详细地址、联络方式等。第三，寻物启事是求人协助寻找的，故除文中写些表谢意的话外，还可以写明给以拾到者必要的酬金之类的话。

(3)落款。落款要署上发文的单位或个人的名称或姓名，并署上发文的日期。

2.失物招领(Found)失物招领并没有硬性的格式规范，而且内容一般都很简练。但需要注意的是，对于拣到的东西说明不能太详细，以防止有人冒领，同时写清楚联系人的联系方式，确保失主可以联系到您。ExampleLOST

Mr.Whitecarelesslylosthissuitcaseat9:30a.m.thisSaturdaywhenhetookabusfromDatongtoTaiyuan.

Itisanorangesquareleathersuitcasewithametalhandleonit.AlabelwithWhite’snameistiedtothehandle.Insidethesuitcasearetwojacketsandacamera.ThereisaChinese-EnglishdictionaryandaletterfromAmericainthepacketonthefrontcoverandinthebackpacketisawalletwith1,000dollarsandatrainticketfromTaiyuantoBeijinginside.

WillthefindergetintouchwithMr.White,please?HistelephonenumberiMr.Whitewillappreciatethefinderverymuch.

TaiyuanBusStation

10thSeptember,2009寻物启事本周六上午九点半，怀特先生乘汽车从大同来太原时，不慎将手提箱丢失。手提箱为橘色、方形、皮制，其上有一个金属提手。左提手上系着一个写有怀特名字的标签。箱内有两件上衣和一部相机。箱前的口袋里有一本汉英词典和一封来自美国的信。箱后口袋里有一个钱包，里面装有1000美元和一张从太原到北京的火车票。请拾到者与怀特先生联系，他的电话号码怀特先生非常感激拾到者。太原汽车站

2009年9月10日FOUND

Abunchofkeyshasbeenfoundinourschoolcanteentodayafterlunchtime.TheownerisadvisedtocontactJaneaoclaimthekeyswithinaweek.

LostandFoundOfficeofComputerDepartment20thSeptember,2011失物招领

Jane于今天中午午餐后在学校餐厅捡到钥匙一串，请失主于一周内与Jane联系并认领失物，电话计算机系失物招领处

2011年9月20日Practice寻物启事今丢失红色公文包一只，公文包上有包含失主信息的名牌，失主的电子邮箱也写在名牌上了，公文包有些损坏。请拾到者通过邮件或电话联系失主，电话失主愿意支付50美元以示酬谢。失主：杰克·斯通

2010年5月15日失物招领昨天下午在操场拾到书包一个，内有几本图书、一个铅笔盒和一块手表，请失主直接联系玛丽·布朗认领失物，联系电拾到者：玛丽·布朗

2011年6月7日Tips当我们发现丢失了物品时，一般会用什么样的方式来表达呢？

A:Excuseme.I’vegotaproblem.IthinkI’velostmywallet.

B:Areyousureit’snotinyourbag?

A:Yes.I’velookedforit.

B:Whydon’tyouchecktheLostPropertyOffice?

A:That’sagoodidea.Thankyou.当我们发现物品丢失时，大多会想到去失物招领处寻找。如果经过询问后还是未找到，我们将怎么做呢？

Kate:Excuseme,couldyouhelpme?

Clerk:Yes.Whatseemstobetheproblem?

Kate:Well,Iwaswonderingifanyonehas