Blockchain practice 3
blockchain is an important concept of bitcoin. It is essentially a disintermediated database. At the same time, as the underlying technology of bitcoin, it is a series of data blocks generated by using cryptographic methods. Each data block contains the information of a bitcoin network transaction, which is used to verify the effectiveness of its information (anti-counterfeiting) and generate the next block
blockchain is a new application mode of distributed data storage, point-to-point transmission, consensus mechanism, encryption algorithm and other computer technologies
in a narrow sense, blockchain is a kind of chain data structure that combines data blocks in a sequential way according to the time sequence, and it can not be tampered with and forged by cryptography
broadly speaking, blockchain technology uses blockchain data structure to verify and store data, uses distributed node consensus algorithm to generate and update data, and uses cryptography to ensure the security of data transmission and access It is a new distributed infrastructure and computing method to program and operate data by using intelligent contract composed of automated script code
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the evolution mode of blockchain is as follows:
& 9642; Blockchain 1.0 - digital currency
▪ Blockchain 2.0 - digital assets and smart contracts
▪ Blockchain 3.0 - Implementation of distributed applications in various instries
blockchain features:
1. Disintermediation. Due to the use of Distributed Accounting and storage, there is no centralized hardware or management organization in the system, the rights and obligations of any node are equal, and the data blocks in the system are jointly maintained by the nodes with maintenance function in the whole system
2. Openness. The system is open. In addition to the private information of all parties to the transaction is encrypted, the data of the blockchain is open to all. Anyone can query the blockchain data and develop related applications through the open interface, so the information of the whole system is highly transparent
3. Autonomy. Blockchain adopts consensus based specifications and Protocols (such as a set of open and transparent algorithms) to enable all nodes in the whole system to exchange data freely and safely in a de trusted environment, so that the trust in "people" is changed into the trust in machines, and any human intervention does not work
The information can not be tampered with. Once the information is verified and added to the blockchain, it will be stored permanently. Unless more than 51% of the nodes in the system can be controlled at the same time, the modification of the database on a single node is invalid. Therefore, the data stability and reliability of the blockchain are extremely high5. Anonymity. Because the exchange between nodes follows a fixed algorithm, the data interaction does not need to be trusted (the program rules in the blockchain will judge whether the activity is effective). Therefore, the counterparties do not need to make the other party trust themselves by disclosing their identities, which is very helpful for the accumulation of credit
some countries have shown great interest in the blockchain technology of decentralized data management framework to store public data. For example, essentia is developing an e-government project with the Central Union of agricultural procers and forest owners in Finland, The project will apply blockchain technology to enable urban and rural residents in Finland to query various records, fully meet the needs of residents and employers, and improve the employment rate. In addition, the use of this technology can also improve the efficiency of government operation, so that residents can easily query ecation, public records, voting and other information
waste recycling
for example, an intelligent waste management system in China adopts the RFID technology of waltonchain company. Using this blockchain application of waltonchain, it can effectively monitor the waste level, so as to improve the management and operation efficiency and resource optimization
identity recognition
chug, a Swiss city known as "encryption Valley", has developed an identity authentication system with its partner uport by using blockchain technology, through which citizens can participate in online voting and proof of residence
border control
essentia has been in contact with the Dutch government, hoping to use its blockchain technology to establish a set of border inspection system for the Dutch government to check passengers between Amsterdam and London. At present, passengers of Eurostar high-speed rail between the two countries need to undergo border control checks at multiple locations. Essentia is working on a blockchain based solution that will securely store passenger data so that inspection records from the Netherlands can also be reviewed by UK Border agencies. Blockchain technology will ensure that the data has not been tampered with and is verifiable and accurate
health care
as we all know, medical records are very scattered and prone to errors. Inconsistent data processing process will make hospitals and clinics often forced to deal with some incorrect or incomplete patient records. For example, Medrec, a blockchain electronic medical record system developed by MIT, uses blockchain technology to promote data sharing. At the same time, it can also provide authentication and confidentiality services
enterprise management
as enterprise customers of Microsoft azure applications, they can make use of blockchain as a service (baas), which will enable enterprises to access smart contracts and blockchain applications in a secure hosting environment. According to media reports, Google is also developing a proprietary blockchain project to support its cloud based business. And alpha, Google's parent company, is developing a distributed accounting project that third parties will be able to use to store data related to Google's cloud services
medical data
medical centers that digitize patient records do not store data among multiple devices. They usually store data on centralized servers, which has become the main target of hackers. The wannacry attack on NHS hospital in the UK proves this. But in addition, even if the security risk is ignored, there is still the problem of fragmentation. At present, there are more than 50 different electronic medical record systems (EHR) operating in hospitals in different cities around the world, and there are usually dozens of different medical application systems in the same city. These independent systems can't perform interoperation, and the data of patients in each hospital can only be distributed in different data storage centers
in the case of patients' life and death, the lack of reliable medical data contrast and slow operation efficiency will be fatal. Essentia's application framework solves all these problems by using blockchain based system, which will store all clinical data of patients, and can access these data immediately regardless of geographical boundaries. In this system, the patient's medical record privacy can also be protected, and only the authorized medical personnel can access it in a specific period of time
Music Proction
one of the main advantages of blockchain technology is that it eliminates unnecessary middlemen or middlemen. The music instry is a typical example. In this instry, if artists are inefficient, they will get very low remuneration. At this time, a number of blockchain based projects have emerged to seek a fairer trading and business environment for music creators, such as artbit, a former gunshot rose drummer Matt Soren as director
carbon compensation
as a highly instrialized country, China's environmental change is huge. In March 2017, IBM and energy blockchain labs jointly launched the hyperledger fabric blockchain project to discover China's carbon assets, which not only creates a measurable and auditable system for tracking carbon emissions, but also provides a tradable market for companies seeking to offset energy consumption and stimulate green instrial practice
supply chain management
supply chain management is considered to be one of the better cases of applying blockchain, because it is very suitable for the express delivery of such goods from delivery to receipt or the whole process from manufacturer to store. IBM and Wal Mart have jointly launched a blockchain food safety alliance in China. The project is also jointly operated with Jingdong company, aiming to improve food delivery tracking and safety assurance, so as to make it easier to trace food safety issues
facts have proved that China is a mature experimental base for blockchain projects, and it is also the location of the world's first blockchain for agricultural procts (5.180, - 0.25, - 4.60%). Louis Dreyfus Co, a world-famous food trader, has established a blockchain technology project in cooperation with Dutch and French banks. Using this project technology, the transaction settlement is faster than traditional methods in the process of selling soybeans to China
diamond instry
De Beers Group, the world's most famous diamond company, has its own blockchain company and has started operation. Its purpose is to "establish a digital record for every diamond registered on the platform". Considering the origin of diamonds, the ethical standards of origin, and the risk of diamond quality, blockchain technology is a good choice, because every record of it is indelible, and it will ensure that the electronic data of each diamond is as permanent as itself
real estate transactions
currently, Ukraine is the first country to use blockchain technology to promote property transactions. Michael Arlington, the founder of techcrunch, a famous technology website and cryptocurrency player, remotely purchased and resold a real estate in Kiev through the smart contract of Ethereum blockchain. This transaction was completed by propy, a start-up company specializing in blockchain real estate transactions
fisheries
blockchain technology is now being used to support the development of sustainable fisheries. Illegal fishing is a common problem in this instry. The distributed ledger technology of blockchain provides a proof of the capture source, processing and sale mode. This "net to table" supply chain allows inspectors to determine whether the fish caught came from a human rights violation area or from a country affected by economic sanctions
art paintings
similar to diamond trading, the art instry relies on the provenance and authenticity of art works. Although the blockchain cannot identify whether a painting is an original or a fake, it can be used to prove the identity of the previous owner of the painting. In addition, blockchain technology is now also used as a means to obtain works of art. It can make tangible goods easily traded and exchanged anywhere in the world without physical transfer from a secure storage place
public facilities
in Freemantle, Australia, a project dedicated to distributed energy and water system management is using blockchain technology, and solar panels (3.340, - 0.06, - 1.76%) are being used in sunny areas to obtain electricity, which is then used to heat water and provide electricity, All these energy conversion and use information will be recorded in the blockchain data
in Chile, the National Energy Commission has started to use the blockchain technology as the verification of the country's energy use data, and some sensitive data will be stored in the blockchain. The application of this technology can be regarded as a means for the modernization and safe operation of power infrastructure in this South American country
LGBT rights
blockchain can help build a "pink economy" and help LGBT communities fight for their own rights without revealing people's identities. This is an extremely important issue, because crimes of discrimination against homosexual groups often occur, especially in countries notorious for human rights violations, Homosexuality is illegal, or at least not allowed
catastrophe bonds
catastrophe bonds may be the only hope for victims of earthquakes, tsunamis and other natural disasters. Blockchain allows fast and transparent reconciliation between the parties, and can ensure that the system can continue to operate normally even under unmanned operation. Now, blockchain has been successfully used in the settlement mechanism of catastrophe bonds
tourism
local institutions in Hawaii are studying how to use blockchain technology to improve the economy, such as opening bitcoin and other monetary payment means to facilitate tourists' transaction of local goods and services. In this way, the Hawaiian government hopes to attract tourists, especially those from Asia, to spend more money in the local area and improve the economic development of Hawaii
homeland security
in 2016, the US Department of Homeland Security (DHS) announced a project that will use blockchain technology as a means of secure storage and capture of data transmission. DHS uses Factom's blockchain technology to encrypt and store data captured by security cameras and other sensors. The application of this blockchain technology will greatly rece the risk of data leakage. At present, the project is still in progress
maritime transportation
it is self-evident that blockchain is used to record ship transportation data. At present, some local shipping projects have adopted distributed ledger technology. In the maritime logistics instry, blockchain technology can make the inevitable cumbersome management proceres in international trade more transparent and orderly. Maersk, one of the world's largest shippers, is a pioneer in the use of blockchain. Today, Yixing international shipping company Zim has also made follow-up use of blockchain technology.
Blockchain is a term in the field of information technology. In essence, it is a shared database. The data or information stored in it is characterized by "unforgeability", "trace in the whole process", "traceability", "openness and transparency" and "collective maintenance". Based on these characteristics, blockchain technology has laid a solid "trust" foundation, created a reliable "cooperation" mechanism, and has broad application prospects
on January 10, 2019, the state Internet Information Office issued the regulations on the management of blockchain information services. In October 24, 2019, ring the eighteenth collective learning of the Central Political Bureau, general secretary Xi Jinping stressed that "block chain as an important breakthrough in core technology and independent innovation", "accelerating the development of block chain technology and instrial innovation". "Blockchain" has entered the public field of vision and become the focus of social attention
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related extension: blockchain financial application:
since 2016, the major financial giants have also carried out blockchain innovation projects to explore the possibility of applying blockchain technology in various financial scenarios. In particular, Puyin group took the lead in creating a "blockchain +" standard digital currency
standard digital currency refers to the process of assets identification, evaluation, right confirmation and insurance completed by a third party organization, which is written into the blockchain through careful digital algorithm to form the standard corresponding relationship between assets and digital currency, which is called standard digital currency
in order to realize the great leap forward development of blockchain finance, promote the new development of China's economy, accelerate the circulation of global assets, and realize the dream of rejuvenation that has been struggling for generations, Puyin group will hold the Guiyang strategic development ceremony of Puyin blockchain finance in Guizhou on December 9, 2016
the meeting will discuss the realization of digital circulation of assets by blockchain, the financial transaction mode of blockchain, and the application of blockchain services and social public instry. This conference will mark the beginning of the application of blockchain finance and the change and development of the new financial ecology
on June 1, 2020, Xinhua news agency was authorized to broadcast the "overall plan for the construction of Hainan free trade port" issued by the CPC Central Committee and the State Council, which will "actively participate in the formulation of international rules for cross-border data flow, and establish standards and rules for data rights confirmation, data trading, data security and blockchain finance" as one of the key tasks of Hainan free trade port before 2035
Public chain, also known as "public chain", refers to the blockchain that anyone in the world can enter the system at any time to read data, send confirmatory transactions and compete for bookkeeping. The public chain is generally considered to be "completely decentralized", because no indivial or institution can control or tamper with the reading and writing of data in it. In terms of application, blockchain public chain mainly includes bitcoin, Ethereum, super ledger, most counterfeit currencies and smart contracts. The ancestor of blockchain public chain is bitcoin blockchain, which has the following characteristics:
1, open source code
upload the code to GitHub, and everyone can get complete blockchain data by downloading, Accept the test of the public
2, complete decentralization
anyone can become a node, each node is open, everyone can participate in the calculation of the blockchain, any node is not permanent, but phased, and any center is not mandatory for nodes. Anyone can read and send transactions, and transactions can be effectively confirmed on the blockchain. Anyone can participate in the consensus process. The consensus process determines whether a block can be added to the blockchain and the exact current state. Everyone can get financial reward from it, which is proportional to their contribution to the consensus process. These public chains are generally considered to be "completely decentralized"
3. Developing decentralized applications
through this public chain, developers can easily develop centralized applications. Public chain can protect the rights and interests of users from the influence of program developers
Blockchain is a new technology, not a disguised form of MLM. It is just claimed by many MLM organizations as "blockchain". In fact, there is no technology. It's just a practice of MLM under the name of "blockchain". The state has issued several announcements to crack down on this kind of MLM. The following is the Xinhua news report on MLM of blockchain:
blockchain is not equal to virtual currency, but also has security risks. Behind the popularity, there is exaggeration with "ulterior motives". Only by removing the flashiness, can the blockchain return to its real application value
invest 80000 yuan, change to 800000 yuan after three months? Shenzhen police cracked a huge fund-raising fraud. Under the guise of blockchain concept and 10 times income, thousands of investors were deeply involved in the case, involving up to 307 million yuan. Under the "veil of mystery" of the blockchain, the illegal elements have taken advantage of their own tricks, and the blockchain has become a "signboard" of economic crimes such as fraud and pyramid selling
why is the blockchain repeatedly "misused" by illegal activities such as pyramid selling fraud? In addition to "unknown", what is the "function" of blockchain technology itself? Since the beginning of this year, with the increase of supervision and the cooling of currency speculation, new opportunities have been brought to the development of blockchain. How about the implementation of blockchain commercial "application" The reporter of outlook news weekly recently concted an investigation
when the three-month "capital release period" promised by the trading platform expired and the staff began to "kick" in the QQ group, Tang Haiyan, who lives in Bao'an District of Shenzhen City, realized that she might have been cheated
previously, Tang Haiyan invested 80000 yuan to buy a virtual currency called "ordinary silver coin" under the introction of her classmates“ The other side said that this currency is the most advanced blockchain technology at present, with Tibetan tea as collateral. He also showed me the "technical white paper". I didn't understand blockchain, so I didn't read it carefully. "
although she doesn't know about blockchain and virtual currency, the high investment income makes Tang Haiyan full of expectations. She told reporters that companies issuing "ordinary silver coins" will regularly split the virtual currency according to the ratio of 1:10, which means that each split will make the value of "ordinary silver coins" in the hands of investors expand 10 times. As long as after a split, her investment of 80000 yuan is equivalent to the purchase of 800000 yuan worth of "ordinary silver coins", which can be sold on the trading platform to obtain huge profits
according to the rules of the trading platform, the newly purchased "ordinary silver coin" cannot be traded immediately, and it must be frozen on the platform for three months before it can enter the "release period". However, after three months, not only did Tang Haiyan not wait for the assets to double, but the 80000 yuan frozen on the platform could not be used for trading
"other investors began to question the authenticity of this investment in QQ group. As a result, the staff of the company kicked these investors out one by one, which made me feel bad." She said
The fact also proves Tang HaiYan's intuition. At the end of March 2018, Shenzhen police detected a huge fund-raising fraud, with the amount of fraud funds as high as 307 million yuan. In this case, Shenzhen Puyin blockchain Group Co., Ltd. involved in the case issued virtual currency in the mode of "blockchain + Tibetan tea" to obtain public deposits. Tang Haiyan was one of the thousands of victimsShenzhen police investigation found that the company claimed that investors could buy and sell "ordinary silver coins" on the virtual trading platform "jucoin net" to earn a price difference
. In fact, the change of its trading price is that the company used investors' investment funds for behind the scenes operation, and once raised the price of "ordinary silver coin" from 0.5 yuan to 10 yuan, so that investors can taste some sweetness. When a large number of investors entered the market, the company continued to cash out through malicious manipulation of the price trend of "ordinary silver coin", which eventually led to the worthlessness of "ordinary silver coin" in the hands of investors
since 2018, engaging in fraud and pyramid selling under the banner of blockchain has become a common "routine" in new criminal tactics. In April 2018, Jinan police dropped a pyramid selling Gang under the guise of "western development", "national poverty alleviation", "original stocks", "blockchain" and "e-commerce", arrested more than 10 major suspects, frozen more than 100 accounts involved, and seized more than 300 million yuan of funds involved
according to Jinan police, huileyi e-commerce company designed a fake virtual disk on the Internet on the ground that the country is vigorously developing the big data instry, and released a variety of virtual currencies such as "precious currency" and "precious currency"
under the guise of giving away, they presented a certain amount of virtual currency to the New MLM staff, with the price of tens of yuan each. Then, through artificial manipulation, they appreciated the virtual currency all the way to more than 100 yuan or even hundreds of yuan, attracting people who did not know the truth to join. Finally, they "cut leeks" through the periodic fluctuation of the so-called "devaluation" of virtual currency, Finally, the purpose of seeking illegal interests is achieved
in Xi'an, a few days ago, the local police successfully cracked a huge network pyramid selling case under the banner of blockchain. According to the police, the suspect, Zheng Mou, has paid a high salary to the 9 network members, such as Zhang and Lee. Since March 28, 2018, he has gathered pyramid selling and network pyramid selling as a means to sell the virtual Datang coins at the consumption era network platform at the price of 3 yuan each, and manipulate the appreciation rate; p>
at the same time, promotion meetings were held in many cities at home and abroad to attract members. According to the development of members, 28 level agents were set up. In just 18 days, the gang developed more than 13000 registered members. At present, it has been found that the case involves 31 provinces, cities and autonomous regions in China, and the fund involved is as high as 86 million yuan
according to Tencent's 2017 pyramid selling situation awareness white paper released by Tencent security joint laboratory, in recent years, all kinds of overseas capital disk, virtual currency and ICO (initial public offering token financing of blockchain project) projects have emerged in an endless stream, which hide many risks such as illegal issuance, untrue projects, cross-border money laundering, fraud and pyramid selling, As a result, a large number of funds flow overseas. Once the market collapses, runs away or loses contact, investors often have no way to complain and the losses are difficult to recover. For example, Baichuan coin, mark coin, beta coin, dark coin, etc
the reporter of lookout Newsweek interviewed in Guangdong, Shandong, Shanghai and other places and learned that most people know that the concept of blockchain is very popular, but they "don't know where it is", and there are different opinions on the specific functions of blockchain: some people think it is used for "investment and financing", "buying and selling currency", while others think it is "a major invention of the same magnitude as the steam engine", Some entrepreneurs are even more eager to seize this "once-in-a-lifetime opportunity to get rich."
many people in the instry said that it is precisely because people have many misunderstandings about blockchain that criminals have opportunities to fish in troubled waters and mislead investors
First, blockchain is not equal to virtual currency. By the end of last year, the number of domestic ICO participants and the total volume of transactions have doubled, a large number of digital currency exchanges have fled overseas, and the agent investment mode has involved more ordinary people in high-risk investmentin many instries, we media and celebrities form interest alliances with issuers and digital exchanges to endorse and create public opinion for the "air currency" project. In December last year, nine departments including the people's Bank of China identified ICO as "suspected of illegal fund-raising, financial fraud, pyramid selling and other illegal and criminal activities"
in the interview, many people told our reporter that the existence of token has built a set of rights and interests mechanism for the development of blockchain technology, which is indispensable for stimulating the prosperity of blockchain applications“ The market practice in the past five years has proved that blockchain applications without equity mechanism are just like market economy without computers connected to the Internet and money, with greatly reced application scenarios and development speed. " An investor in Shanghai said
in fact, the token represented by bitcoin is only one of the earliest procts to verify the blockchain technology, and the two can not be equated, and the existence of token has obviously negative effects on the development of blockchain
Xiao Wei, chief engineer of network blockchain, told this reporter that the myth of ICO's sudden wealth shakes the R & D concentration of blockchain technical talents, and the myth of "sudden wealth" with hundreds of times of return tests the patience of blockchain technical R & D talents“ Many of the "comrades in arms" in the circle who used to do research and development of blockchain technology have gone to issue coins, and now few of them can insist on doing research and development and application of technology. "
Xu zewei, Secretary of the Party committee of Beijing Internet Finance Instry Association, said that under the background of China's ban on ICO, many domestic start-ups promoting blockchain applications are "selling dog meat with sheep's pawn" and financing through concept packaging of worthless tokens“ ICO has polluted the good atmosphere of innovation and entrepreneurship, and created a kind of speculative proct. Many young people are not thinking about entrepreneurship, but are thinking about issuing money, which makes us have the illusion of getting rich overnight. "
at present, more and more people in the instry begin to think about whether the development of blockchain must rely on the issuance of tokens to achieve incentives. Guo Dagang, Secretary General of Beijing Internet Finance Instry Association, told this reporter that the so-called incentive mechanism is only the theoretical basis for the project party to issue tokens for itself. Huo Xuewen, director of Beijing Municipal Bureau of financial work, also believes that if blockchain does not get rid of the dilemma of issuing currency, it will never find a legal landing mechanism
secondly, blockchain is not omnipotent and its security is at risk. Blockchain is generally considered to achieve three functions:
first, the data stored on the blockchain can not be tampered or forged, and the data has high credibility and credibility; Second, the whole process of the transaction can be traced, which can achieve accurate responsibility tracking; Third, the embedded smart contract in the blockchain can be executed automatically based on the contract, so as to improve work efficiency and rece the risk of default. It is generally believed that blockchain has broad application prospects in finance, logistics, trade and other fields
in fact, blockchain is not omnipotent, and its function has many limitations. It is generally believed that, according to the characteristics of cryptography, in order to tamper or falsify in the blockchain, more than 51% of the nodes need to be controlled in theory. When there are enough nodes in the blockchain, it is difficult to tamper with the trust creation mechanism widely participated by the public
However, in reality, digital currency exchanges are frequently attacked or even stolen. On June 20, 2018, bithumb exchange of South Korea announced on its official website that the exchange had been attacked by hackers and stolen 35 billion won, about 32 million US dollars of cryptocurrency Ji Xinhua, known as the first generation of "hackers" in China, said that the blockchain will continue to face attacks, and the process of uploading data to the blockchain is prone to information leakage. Some people in the instry worry that once the super computing power of quantum computing is realized, it will also have a direct impact on the blockchainZhao Yao, a special researcher of the Institute of finance of the Chinese Academy of Social Sciences, told this reporter that the academic community has confirmed as early as 2013 that the blockchain is not perfect and there are many "cheating" strategies. As long as there are enough economic incentives, controlling attacks of more than 51% nodes does not only exist in theory
Zeng Guang, Secretary General of Shenzhen Internet Finance Association, said that the blockchain technology itself does not have the ability to do so