1、BlockchainBlockchain is a term used in information technology.In essence,it is a shared database,in which the data or information is stored,with such characteristics as non-forgery,”trace,”traceable,open and transparent and collective maintenance.Based on these characteristics,blockchain technology
2、has laid a solid foundation of trust,created a reliable cooperation mechanism,and has a broad application prospect.blockchain n.区块链forgery n.伪造，伪造物traceable a.可追踪的，可描绘的transparent a.透明的，显然的A blockchain,originally block chain,is a growing list of records called blocks,which are linked using cryptogra
3、phy.Each block contains a cryptographic hash of the previous block,a timestamp,and transaction data(generally represented as a Merkle tree).By design,a blockchain is resistant to modification of the data.It is an open,distributed ledger that can record transactions between two parties efficiently an
4、d in a verifiable and permanent way.For use as a distributed ledger,a blockchain is typically managed by a peer-to-peer network collectively adhering to a protocol for inter-node communication and validating new blocks.cryptography n.密码学，密码hash n.哈希，散列timestamp n.时间戳，时间标记resistant a.抵抗的，反抗的modificat
5、ion n.修改，修正，修饰ledger n.总账，账簿permanent a.永久的，永恒的validating a.确认的，有效的 Once recorded,the data in any given block cannot be altered retroactively without alteration of all subsequent blocks,which requires consensus of the network majority.Although blockchain records are not unalterable,blockchains may b
6、e considered secure by design.retroactively ad.追溯的，逆动的unalterable a.不变的，不能改变的Blockchain was invented by a person using the name Satoshi Nakamoto in 2008 to serve as the public transaction ledger of the cryptocurrency bitcoin.The identity of Satoshi Nakamoto is unknown.The invention of the blockchain
7、 for bitcoin made it the first digital currency to solve the double-spending problem without the need of a trusted authority or central server.decentralized a.分散管理的，去中心的consensus n.一致，共识bitcoin n.比特币The bitcoin design has inspired other applications,and blockchains which are readable by the public a
8、re widely used by cryptocurrencies.Blockchain is considered a type of payment.Private blockchains have been proposed for business use.Sources such as Computerworld called the marketing of such blockchains without a proper security model snake oil.inspire v.激发，鼓舞cryptocurrency The first work on a cry
9、ptographically secured chain of blocks was described in 1991 by Stuart Haber and W.Scott Stornetta.They wanted to implement a system where document timestamps could not be tampered with.In 1992,Bayer,Haber and Stornetta incorporated Merkle trees to the design,which improved its efficiency by allowin
10、g several document certificates to be collected into one block.Cryptographically implement v.实施，执行tamper v.做手脚，破坏The first blockchain was conceptualized by a person(or group of people)known as Satoshi Nakamoto in 2008.Nakamoto improved the design in an important way using a Hashcash-like method to a
11、dd blocks to the chain without requiring them to be signed by a trusted party.The design was implemented the following year by Nakamoto as a core component of the cryptocurrency bitcoin,where it serves as the public ledger for all transactions on the network.conceptualize v.使概念化ledger n.总账 Currently
12、,there are three types of blockchain networks public blockchains,private blockchains and consortium blockchains.A public blockchain has absolutely no access restrictions.Anyone with an Internet connection can send transactions to it as well as become a validator(i.e.,participate in the execution of
13、a consensus protocol).Some of the largest,most known public blockchains are the bitcoin blockchain and the Ethereum blockchain.restriction n.限制，约束validator n.验证器，验证程序A private blockchain is permissioned.One cannot join it unless invited by the network administrators.Participant and validator access
14、is restricted.This type of blockchains can be considered a middle-ground for companies that are interested in the blockchain technology in general but are not comfortable with a level of control offered by public networks.Typically,they seek to incorporate blockchain into their accounting and record
15、-keeping procedures without sacrificing autonomy and running the risk of exposing sensitive data to the public internet.permission n.允许，许可participant n.参与者，参加者sacrifice v.牺牲，献祭autonomy n.自制，自主权 A consortium blockchain is often said to be semi-decentralized.It,too,is permissioned but instead of a sin
16、gle organization controlling it,a number of companies might each operate a node on such a network.The administrators of a consortium chain restrict users reading rights as they see fit and only allow a limited set of trusted nodes to execute a consensus protocol.consortium n.财团，联盟execute v.实行，执行cons
17、ensus n.一致，共识A blockchain is a decentralized,distributed and public digital ledger that is used to record transactions across many computers so that any involved record cannot be altered retroactively,without the alteration of all subsequent blocks.This allows the participants to verify and audit tr
18、ansactions independently and relatively inexpensively.A blockchain database is managed autonomously using a peer-to-peer network and a distributed time stamping server.Participant verify v.核实，查证inexpensively ad.廉价地，不贵地The use of a blockchain removes the characteristic of infinite reproducibility fro
19、m a digital asset.It confirms that each unit of value was transferred only once,solving the long-standing problem of double spending11.A blockchain has been described as a value-exchange protocol.A blockchain can maintain title rights because,when properly set up to detail the exchange agreement,it
20、provides a record that compels offer and acceptance12.infinite a.无限的，无穷的reproducibility n.再现性，再生性compel v.强迫，迫使By storing data across its peer-to-peer network,the blockchain eliminates a number of risks that come with data being held centrally.Peer-to-peer blockchain networks lack centralized points
21、 of vulnerability that computer crackers can exploit;likewise,it has no central point of failure.Blockchain security methods include the use of public-key cryptography.eliminate v.消除，排除vulnerability n.易损性，脆弱性cracker n.黑客，解密高手exploit v.开发，利用A public key(a long,random-looking string of numbers)is an a
22、ddress on the blockchain.Value tokens sent across the network are recorded as belonging to that address.A private key is like a password that gives its owner access to their digital assets.Data stored on the blockchain is generally considered incorruptible.token n.代币，记号，令牌incorruptible a.清廉的，不能收买的 O
23、pen blockchains are more user-friendly than some traditional ownership records,which,while open to the public,still require physical access to view14.Because all early blockchains were permissionless,controversy has arisen over the blockchain definition.An issue in this ongoing debate is whether a p
24、rivate system with verifiers tasked and authorized(permissioned)by a central authority should be considered a blockchain.permissionless n.无需许可verifier Proponents of permissioned or private chains argue that the term blockchain may be applied to any data structure that batches data into time-stamped
25、blocks.The great advantage to an open,permissionless,or public,blockchain network is that guarding against bad actors is not required and no access control is needed.This means that applications can be added to the network without the approval or trust of others,using the blockchain as a transport l
26、ayer.proponent n.支持者，建议者batch n.一批，批处理 Blockchain technology can be integrated into multiple areas.The primary use of blockchains today is as a distributed ledger for cryptocurrencies,most notably bitcoin.Most cryptocurrencies use blockchain technology to record transactions.For example,the bitcoin
27、network and Ethereum network are both based on blockchain.Blockchain-based smart contracts are proposed contracts that could be partially or fully executed or enforced without human interaction.One of the main objectives of a smart contract is automated escrow.An IMF staff discussion reported that s
28、mart contracts based on blockchain technology might reduce moral hazards and optimize the use of contracts in general.But no viable smart contract systems have yet emerged.Due to the lack of widespread use their legal status is unclear.contract n.合同，契约execute v.实行，执行escrow n.第三方托管，第三方支付hazard n.危险，风
29、险optimize v.使最优化，使完善Major portions of the financial industry are implementing distributed ledgers for use in banking.Banks are interested in this technology because it has potential to speed up back office settlement systems.Some video games are based on blockchain technology.The first such game,Hun
30、tercoin,was released in February,2016.Another blockchain game is CryptoKitties,launched in November 2017.The game made headlines in December 2017 when a cryptokitty character-an-in game virtual pet-was sold for US$100,000.There are a number of efforts and industry organizations working to employ blockchains in supply chain logistics and supply chain management.logistics n.物流，后勤
