《出版社通信英语》课件Blockchain-区块链

BlockchainBlockchainisatermusedininformationtechnology.Inessence,itisashareddatabase,inwhichthedataorinformationisstored,withsuchcharacteristicsas"non-forgery",”trace",”traceable","openandtransparent"and"collectivemaintenance".Basedonthesecharacteristics,blockchaintechnologyhaslaidasolidfoundationof"trust",createdareliable"cooperation"mechanism,andhasabroadapplicationprospect.blockchainn.区块链forgeryn.伪造，伪造物traceablea.可追踪的，可描绘的transparenta.透明的，显然的A

blockchain,

originally

blockchain,isagrowinglistof

recordscalled

blocks,whicharelinkedusing

cryptography.

Eachblockcontainsa

cryptographichash

ofthepreviousblock,a

timestamp,andtransactiondata(generallyrepresentedasa

Merkletree).Bydesign,ablockchainisresistanttomodificationofthedata.Itis"anopen,distributedledgerthatcanrecordtransactionsbetweentwopartiesefficientlyandinaverifiableandpermanentway".Foruseasa

distributedledger,ablockchainistypicallymanagedbya

peer-to-peer

networkcollectivelyadheringtoa

protocol

forinter-nodecommunicationandvalidatingnewblocks.cryptographyn.密码学，密码hashn.哈希，散列timestampn.时间戳，时间标记resistanta.抵抗的，反抗的modificationn.修改，修正，修饰ledgern.总账，账簿permanenta.永久的，永恒的validatinga.确认的，有效的

Oncerecorded,thedatainanygivenblockcannotbealteredretroactivelywithoutalterationofallsubsequentblocks,whichrequiresconsensusofthenetworkmajority.Althoughblockchainrecordsarenotunalterable,blockchainsmaybeconsidered

securebydesign.retroactivelyad.追溯的，逆动的unalterablea.不变的，不能改变的Blockchainwasinventedbyapersonusingthename

SatoshiNakamoto

in2008toserveasthepublictransaction

ledger

ofthe

cryptocurrency

bitcoin.TheidentityofSatoshiNakamotoisunknown.Theinventionoftheblockchainforbitcoinmadeitthefirstdigitalcurrencytosolvethe

double-spending

problemwithouttheneedofatrustedauthorityorcentral

server.decentralizeda.分散管理的，去中心的consensusn.一致，共识bitcoinn.比特币Thebitcoindesignhasinspiredotherapplications,andblockchainswhicharereadablebythepublicarewidelyusedby

cryptocurrencies.Blockchainisconsideredatypeof

payment.Privateblockchainshavebeenproposedforbusinessuse.Sourcessuchas

Computerworld

calledthemarketingofsuchblockchainswithoutapropersecuritymodel"snakeoil".inspirev.激发，鼓舞cryptocurrency

Thefirstworkonacryptographicallysecuredchainofblockswasdescribedin1991byStuartHaberandW.ScottStornetta.Theywantedtoimplementasystemwheredocumenttimestampscouldnotbetamperedwith.In1992,Bayer,HaberandStornettaincorporated

Merkletrees

tothedesign,whichimproveditsefficiencybyallowingseveraldocumentcertificatestobecollectedintooneblock.Cryptographicallyimplementv.实施，执行tamperv.做手脚，破坏Thefirstblockchainwasconceptualizedbyaperson(orgroupofpeople)knownas

SatoshiNakamoto

in2008.Nakamotoimprovedthedesigninanimportantwayusinga

Hashcash-likemethodtoaddblockstothechainwithoutrequiringthemtobesignedbyatrustedparty.

ThedesignwasimplementedthefollowingyearbyNakamotoasacorecomponentofthecryptocurrency

bitcoin,whereitservesasthepublic

ledger

foralltransactionsonthenetwork.conceptualizev.使概念化ledgern.总账

Currently,therearethreetypesofblockchainnetworks—publicblockchains,privateblockchainsand

consortium

blockchains.Apublicblockchainhasabsolutelynoaccessrestrictions.Anyonewithan

Internet

connectioncansend

transactions

toitaswellasbecomea

validator

(i.e.,participateintheexecutionofa

consensusprotocol).Someofthelargest,mostknownpublicblockchainsarethebitcoinblockchainandtheEthereumblockchain.restrictionn.限制，约束validatorn.验证器，验证程序Aprivateblockchainispermissioned.

Onecannotjoinitunlessinvitedbythenetworkadministrators.Participantandvalidatoraccessisrestricted.Thistypeofblockchainscanbeconsideredamiddle-groundforcompaniesthatareinterestedintheblockchaintechnologyingeneralbutarenotcomfortablewithalevelofcontrolofferedbypublicnetworks.Typically,theyseekto

incorporate

blockchainintotheiraccountingandrecord-keepingprocedureswithoutsacrificingautonomyandrunningtheriskofexposingsensitivedatatothepublicinternet.permissionn.允许，许可participantn.参与者，参加者sacrificev.牺牲，献祭autonomyn.自制，自主权

Aconsortiumblockchainisoftensaidtobesemi-decentralized.It,too,ispermissionedbutinsteadofasingle

organization

controllingit,anumberofcompaniesmighteachoperatea

node

onsuchanetwork.Theadministratorsofaconsortiumchainrestrictusers'readingrightsastheyseefitandonlyallowalimitedsetoftrustednodestoexecuteaconsensusprotocol.consortiumn.财团，联盟executev.实行，执行consensusn.一致，共识Ablockchainisa

decentralized,

distributed

andpublicdigitalledgerthatisusedtorecordtransactionsacrossmanycomputerssothatanyinvolved

record

cannotbealteredretroactively,withoutthealterationofallsubsequentblocks.Thisallowstheparticipantstoverifyandaudittransactionsindependentlyandrelativelyinexpensively.Ablockchaindatabaseismanagedautonomouslyusinga

peer-to-peer

networkandadistributedtimestampingserver.Participantverifyv.核实，查证inexpensivelyad.廉价地，不贵地Theuseofablockchainremovesthecharacteristicofinfinite

reproducibility

fromadigitalasset.Itconfirmsthateachunitofvaluewastransferredonlyonce,solvingthelong-standingproblemof

doublespending11.Ablockchainhasbeendescribedasa

value-exchangeprotocol.

Ablockchaincanmaintain

titlerights

because,whenproperlysetuptodetailtheexchangeagreement,itprovidesarecordthatcompels

offerandacceptance12.infinitea.无限的，无穷的reproducibilityn.再现性，再生性compelv.强迫，迫使Bystoringdataacrossitspeer-to-peernetwork,theblockchaineliminatesanumberofrisksthatcomewithdatabeingheldcentrally.Peer-to-peerblockchainnetworkslackcentralizedpointsofvulnerabilitythat

computercrackers

canexploit;likewise,ithasnocentralpointof

failure.Blockchainsecuritymethodsincludetheuseof

public-keycryptography.

eliminatev.消除，排除vulnerabilityn.易损性，脆弱性crackern.黑客，解密高手exploitv.开发，利用A

publickey

(along,random-lookingstringofnumbers)isanaddressontheblockchain.Valuetokenssentacrossthenetworkarerecordedasbelongingtothataddress.A

privatekey

islikeapasswordthatgivesitsowneraccesstotheirdigitalassets.Datastoredontheblockchainisgenerallyconsideredincorruptible.tokenn.代币，记号，令牌incorruptiblea.清廉的，不能收买的

Openblockchainsaremore

user-friendly

thansometraditionalownershiprecords,which,whileopentothepublic,stillrequirephysicalaccesstoview14.Becauseallearlyblockchainswerepermissionless,controversyhasarisenovertheblockchaindefinition.Anissueinthisongoingdebateiswhetheraprivatesystemwithverifierstaskedandauthorized(permissioned)byacentralauthorityshouldbeconsideredablockchain.

permissionlessn.无需许可verifierProponentsofpermissionedorprivatechainsarguethattheterm"blockchain"maybeappliedtoanydatastructurethatbatchesdataintotime-stampedblocks.Thegreatadvantagetoanopen,permissionless,orpublic,blockchainnetworkisthatguardingagainstbadactorsisnotrequiredandno

accesscontrol

isneeded.Thismeansthatapplicationscanbeaddedtothenetworkwithouttheapprovalortrustofothers,usingtheblockchainasa

ponentn.支持者，建议者batchn.一批，批处理

Blockchaintechnologycanbeintegratedintomultipleareas.Theprimaryuseofblockchainstodayisasa

distributedledger

for

cryptocurrencies,mostnotably

bitcoin.Mostcryptocurrenciesuseblockchaintechnologytorecordtransactions.Forexample,the

bitcoinnetwork

and

Ethereum

networkarebothbasedonblockchain.

Blockchain-based

smartcontracts

areproposedcontractsthatcouldbepartiallyorfullyexecutedorenforcedwithouthumaninteraction.

Oneofthemainobjectivesofasmartcontractis

automated

escrow.An

IMF

staffdiscussionreportedthatsmartcontractsbasedonblockchaintechnologymightreduce

moralhazards

andoptimizetheuseofcontractsingenera