数字签名通常使用()方式。

A、公钥密码体系中的私钥
B、公钥密码系统中的私钥对数字摘要进行加密
C、密钥密码体系
D、公钥密码体系中公钥对数字摘要进行加密
查看答案
正确答案:

B

答案解析:

暂无解析

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题目:CongratulationLetter祝贺与慰问

Mobilephonesandtheinternetplayanimportantpartinthewaywhichpeoplerelatetooneanothersocially.Doyouthinktheadvantagesoutweighthedisadvantages?

SellingDigitalMusicwithoutCopy-protectionMakesSense

A. Itwasuncharacteristicallylow-keyfortheindustry’sgreatestshowman.ButtheessaypublishedthisweekbySteveJobs,thebossofApple,onhisfirm’swebsiteundertheunassumingtitle“ThoughtsonMusic”hasnonethelessprovokedavigorousdebateaboutthefutureofdigitalmusic,whichAppledominateswithitsiPodmusic-playerandiTunesmusic-store.Atissueis“digitalrightsmanagement”(DRM)—thetechnologyguardingdownloadedmusicagainsttheft.SincethereisnocommonstandardforDRM,italsohastheside-effectthatsongspurchasedforonetypeofmusic-playermaynotworkonanother.Apple’sDRMsystem,calledFairPlay,isthemostwidespread.SoitcameasasurprisewhenMr.JobscalledforDRMfordigitalmusictobeabolished.

B. ThisisachangeoftackforApple.IthascomeunderfirefromEuropeanregulatorswhoclaimthatitsrefusaltolicenseFairPlaytootherfirmshas“lockedin”customers.SincemusicfromtheiTunesstorecannotbeplayedonnon-iPodmusic-players(atleastnotwithoutalotoffiddling),anyiTunesbuyerwillbedeterredfromswitchingtoadevicemadebyarivalfirm,suchasSonyorMicrosoft.WhenFrenchlawmakersdraftedabilllastyearcompellingAppletoopenupFairPlaytorivals,thecompanywarnedof“state-sponsoredpiracy”.OnlyDRM,itimplied,couldkeepthepiratesatbay.

C. ThisweekMr.JobsgaveanotherexplanationforhisformerdefenceofDRM:therecordcompaniesmadehimdoit.TheywouldmaketheirmusicavailabletotheiTunesstoreonlyifAppleagreedtoprotectitusingDRM.TheycanstillwithdrawtheircataloguesiftheDRMsystemiscompromised.ApplecannotlicenseFairPlaytoothers,saysMrJobs,becauseitwoulddependonthemtoproducesecurityfixespromptly.AllDRMdoesisrestrictconsumerchoiceandprovideabarriertoentry,saysMrJobs;withoutittherewouldbefarmorestoresandplayers,andfarmoreinnovation.So,hesuggests,whynotdoawaywithDRMandsellmusicunprotected?“Thisisclearlythebestalternativeforconsumers,”hedeclares,“andApplewouldembraceitinaheartbeat.”

D. Whythesuddenchangeofheart?MrJobsseemschieflyconcernedwithgettingEurope’sregulatorsoffhisback.RatherthancomplainingtoAppleaboutitsuseofDRM,hesuggests,“thoseunhappywiththecurrentsituationshouldredirecttheirenergiestowardspersuadingthemusiccompaniestoselltheirmusicDRM-free.”Twoandahalfofthefourbigrecordcompanies,hehelpfullypointsout,areEuropean-owned.MrJobsalsohopestopainthimselfasaconsumerchampion.AppleresentsaccusationsthatithasbecometheMicrosoftofdigitalmusic.

E. Applecanaffordtoembraceopencompetitioninmusicplayersandonlinestores.Consumerswouldgravitatetothebestplayerandthebeststore,andatthemomentthatstillmeansApple’s.MrJobsisevidentlyunfazedbyrivalstotheiPod.Sinceonly3%ofthemusicinatypicaliTuneslibraryisprotected,mostofitcanalreadybeusedonotherplayerstoday,henotes.(AndeventheprotectedtrackscanbeburnedontoaCDandthenre-ripped.)SoApple’sdominanceevidentlydependsfarmoreonbrandingandeaseofusethanDRM-related“lockin”.

F. ThemusicgiantsaretryingDRM-freedownloads.Lotsofsmallerlabelsalreadysellmusicthatway.Havingseenwhichwaythewindisblowing,MrJobsnowwantstobeseennotasDRM’sdefender,butasaconsumerchampionwhohelpedinitsdownfall.Wouldn’titleadtoasurgeinpiracy?No,becausemostmusicisstillsoldunprotectedonCDs,peoplewishingtostealmusicalreadycandoso.Indeed,scrappingDRMwouldprobablyincreaseonline-musicsalesbyreducingconfusionandincompatibility.Withtheleadingonlinestore,Applewouldbenefitmost.MrJobs’sargument,inshort,istransparentlyself-serving.Italsohappenstoberight.

NotestoReadingPassage1

1.low-key:

抑制的,受约束的,屈服的

2.showman:

开展览会的人,出风头的人物

3.unassuming:

谦逊的,不夸耀的,不装腔作势的

4.iPod:

(苹果公司出产的)音乐播放器

5.iTunesstore:

(苹果公司出产的)在线音乐商店

6.getoffperson’sback:

不再找某人的麻烦,摆脱某人的纠缠

7.gravitate:

受吸引,倾向于

8.unfazed:

不再担忧,不被打扰

Questions1-7

DothefollowingstatemetsreflecttheclaimsofthewriterinReadingPassage1?

WriteyouranswerinBoxes1-7onyouranswersheet.

TRUEifthestatementrefletstheclaimsofthewriter

FALSEifthestatementcontradictstheclaimsofthewriter

NOTGIVENifitisimpossbiletosaywhatthewriterthinksaboutthis

1.AppleenjoysacontrollingpositionindigitalmusicmarketwithitsiPodmusic-playerandiTunesmusic-store.

2.DRMisagovernmentdecreeissuedwithapurposetoprotectdownloadedmusicfromtheftbyconsumers.

3.LackofstandardizationinDRMmakessongsboughtforonekindofmusicplayermaynotfunctiononanother.

4.ApplehasbeencriticizedbyEuropeanregulatorssinceithasrefusedtograntalicenseFairPlaytootherfirms.

5.Allmusiccanbeeasilyplayedonnon-iPodmusicdevicesfromSonyorMicrosoftwithouttoomuchfiddling.

6.AppledependsfarmoreonDRMratherthanbrandingforitsdominanceofthedigitalmusicdevices.

7.IfDRMwascancelled,Sonywouldcertainlydominatetheinternationaldigitalmusicmarket.

Questions8-10

ChoosetheappropriatelettersA-Dandwritetheminboxes8-10onyouranswesheet.

8.WhichofthefollowingstatementsaboutMr.Jobs’ideaofDRMisNOTTRUE?

A.DRMplacesrestrictionsonconsumer’choiceofdigitalmusicproductsavailable.

B.DRMcomplesiTunesbuyerstoswitchtoadevicemadebySonyorMicrosoft.

C.DRMconstitutesabarrierforpotentialconsumerstoenterdigitalmusicmarkets.

D.DRMhindersdevelopmentofmorestoresandplayersandtechnicalinnovation.

9.Theword“unfazed”inline3ofparagraphE,means___________.

A.refused

B.welcomed

C.notbothered

D.notwellreceived

10.WhichofthefollowingstatementsisTRUEifDRMwasscapped?

A.Sonywouldgainthemostprofit.

B.Morecustomerswouldbe“lockedin”.

C.Asuddenincreaseinpiracywouldoccur.

D.Online-musicsaleswouldprobablydecrease.

Questions11-14

Completethenotesbelow.

ChooseNOMORETHANTHREEWORDSfromReadingPassage1foreachanswer.

Writeyouranswersinboxes11-14onyouranswersheet.

Mr.SteveJobs,thebossofApple,explainsthereasonwhyheusedtodefendDRM,sayingthatthecompanywasforcedtodoso:therecordcompanieswouldmaketheirmusicaccessibleto…11...onlyiftheyagreedtoprotectitusingDRM;theycanstill…12…iftheDRMsystemiscompromised.HealsoprovidesthereasonwhyAppledidnotlicenseFairPlaytoothers:thecompanyreliesonthemto…13….ButnowhechangeshismindwithapossibleexpectationthatEurope’sregulatorswouldnottroublehimanymoreinthefuture.Heproposesthatthosewhoareunsatisfactorywiththecurrentsituationindigitalmusicmarketshould…14…towardspersuadethemusiccompaniestoselltheirmusicDRM-free.

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