The 41st blockchain
We need to establish data layer, network layer, consensus layer, incentive layer, contract layer and application layer
1. The data layer encapsulates the underlying data blocks and related basic data and algorithms such as data encryption and time stamp
2. The network layer includes distributed networking mechanism, data transmission mechanism and data verification mechanism
The consensus layer mainly encapsulates all kinds of consensus algorithms of network nodes The incentive layer integrates economic factors into the blockchain technology system, mainly including the issuing mechanism and distribution mechanism of economic incentives5. The contract layer mainly encapsulates all kinds of scripts, algorithms and smart contracts, which is the basis of the programmable characteristics of blockchain
6. The application layer encapsulates various application scenarios and cases of blockchain
, general secretary of the CPC Central Committee, stressed in the eighteenth collective learning of the Central Political Bureau, "block chain as an important breakthrough in core technology and independent innovation", "accelerating the development of block chain technology and instrial innovation". <
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the forward-looking judgment of the CPC Central Committee has brought the "blockchain" into the public view and become the common focus of financial capital, real economy and public opinion
from network power to big data, from media integration to blockchain, the Politburo of the CPC Central Committee has collectively studied and aimed at the forefront of technological change, showing the direction, foresight and foresight of the CPC Central Committee, leading the pace of China's instrial change and economic transformation. This collective study of the Political Bureau of the Central Committee of the CPC, with special emphasis on "blockchain", has opened up an imaginary space for the development and application of blockchain
from the perspective of science and technology, blockchain involves many scientific and technological issues such as mathematics, cryptography, Internet and computer programming. From the perspective of application, in short, blockchain is a distributed shared ledger and database, which is decentralized, tamper proof, traceable, collective maintenance, open and transparent
these features ensure the "honesty" and "transparency" of the blockchain, and lay the foundation for creating trust in the blockchain. The rich application scenarios of blockchain are basically based on the fact that blockchain can solve the problem of information asymmetry, and realize the cooperative trust and concerted action among multiple agents
1. Germination stage: the real germination stage of blockchain was from 2007 to 2009. In 2008, a Japanese American with the pseudonym of Nakamoto first expounded a new fantasy report on electronic money in the form of a synonym on the cryptography discussion group, and bitcoin came out. As early as 2007, Nakamoto began to explore a series of new technologies to create a new currency. On October 31, 2008, bitcoin white paper was released, and on January 3, 2009, bitcoin system officially began to operate
the main technologies supporting bitcoin system include hash function, distributed ledger, blockchain and asymmetric encryption; It can be seen that these technologies build the initial version of the blockchain, and it can also be said that the blockchain is the underlying technology of bitcoin. During the three years from 2007 to 2009, bitcoin was an experimental stage in which a very small number of people participated, and the real commercial activities had not really started
2. "Geek" niche stage: here, "geek" refers to people who are crazy about Internet technology and take technological innovation as fashion and life. On February 6, 2010, the first exchange of bitcoin appeared. On May 22 of the same year, someone bought two hamburgers with 10000 bitcoins. On July 17 of the same year, the exchange Mt. GOx was established, marking the official inflow of bitcoin into the market. Nevertheless, the only people who can really understand and enter the market to participate in bitcoin trading are geeks who are keen on Internet technology. They discuss bitcoin technology on the forum, mine for bitcoin on their own computers, and then buy and sell bitcoin on Mt. GOx. Now these geeks have become billionaires
3. Market brewing stage: the price of bitcoin was $13 at the beginning of 2013, but on March 18 of the same year, the government of Cyprus closed the bank and stock market e to the financial crisis, which made the price of bitcoin soar, and the highest price rose to $266 in April. On August 20 of the same year, the German government confirmed the currency status of bitcoin. On October 14, China network announced the opening of bitcoin payment channel. In November, the US Senate hearing also confirmed the legitimacy of bitcoin. On November 19, the price of bitcoin rose to US $1242, forming a new high. Nevertheless, the foundation for blockchain to enter the mainstream social economy is not yet available, and the soaring price of bitcoin is only e to over optimistic expectations. The containment of China's banking system, the collapse of Mt. GOx and other events made the price of bitcoin continue to fall. At the beginning of 2015, the price of bitcoin has dropped below $200. From 2013 to the beginning of 2015, the public began to understand bitcoin and blockchain
4. The mainstream period of blockchain: on June 23, 2016, the United Kingdom left the European Union, the fifth nuclear test of North Korea in September, Trump's election in November and other events, the uncertainty of the world's mainstream economy led to the recovery of bitcoin with the function of risk aversion. The market demand was large, and the increase of trading volume made the price of bitcoin soar from $400 in 2016 to $20000 in 2017, The wealth effect of bitcoin and the transaction overflow caused by network congestion of bitcoin have led to the outbreak of other series of virtual currencies, as well as a variety of blockchain applications, resulting in the emergence of a large number of blockchain assets that are 100 times, even 1000 times and 10000 times, which has aroused the crazy pursuit of the world, Subsequently, the Chicago Mercantile Exchange launched bitcoin futures trading, marking that bitcoin has officially entered the mainstream investment proct series, and bitcoin and blockchain have entered the global attention
5. Instry landing stage: after the market frenzy in 2017, the virtual currency and blockchain have been adjusted in terms of market, supervision, cognition, etc. in 2018, returning to rationality. In 2017, many blockchain projects that follow the blockchain technology will graally die out with the cooling of the market, and the projects with real blockchain applications will be initially implemented. 2018 is not only the first year of the blockchain, but also a gold rush period for the blockchain. After the waves wash away the sand, what remains is relatively good gold
from the perspective of the history of blockchain development, blockchain technology is not yet mature and is currently in the growth period. The specific practical application of blockchain is only used in the financial field. It still needs a long way to go to apply blockchain from other instries. However, we should grasp the trend of blockchain and actively learn from the new field of blockchain.
The strict definition of blockchain refers to the distributed database technology that multiple nodes in peer-to-peer network jointly maintain a continuously growing list ledger constructed by time stamp and orderly record data blocks through consensus mechanism based on cryptography technology. This technical solution allows any number of nodes in the participating system to calculate and record all the information exchange data in the system in a period of time to a data block through cryptography algorithm, and generate the fingerprint of the data block for linking the next data block and checking. All participating nodes in the system jointly determine whether the record is true
blockchain is a technical solution similar to NoSQL (non relational database). It is not a specific technology, and can be implemented through many programming languages and architectures. There are many ways to realize blockchain, including pow (proof of work), POS (proof of stake), dpos (delegate proof of stake), etc
the concept of blockchain was first proposed in the paper "bitcoin: a peer-to-peer electronic cash system" by indivials (or groups) who call themselves Satoshi Nakamoto. Therefore, bitcoin can be regarded as the first application of blockchain in the field of financial payment
< H2 > [popular explanation]no matter how big the system or how small the website is, there is a database behind it. So who will maintain this database? In general, who is responsible for the operation of the network or system, then who is responsible for the maintenance. If it is wechat database, it must be maintained by Tencent team, and Taobao database is maintained by Alibaba team. We must think that this way is natural, but blockchain technology is not
if we think of the database as a book, for example, Alipay is a typical account book. Any change of data is bookkeeping. We can think of database maintenance as a very simple way of accounting. In the world of blockchain, everyone in the blockchain system has the opportunity to participate in bookkeeping. The system will select the fastest and best bookkeeper in a period of time, maybe within ten seconds or ten minutes. The bookkeeper will record the changes of the database and the account book in a block. We can think of this block as a page. After the system confirms that the records are correct, the system will record the changes of the database and the account book in a block, It will link the fingerprint of the past account book to this paper, and then send this paper to everyone else in the whole system. Then, over and over again, the system will look for the next person with fast and good bookkeeping, and everyone else in the system will get a of the whole ledger. This means that everyone as like as two peas in the system is called Blockchain. It is also called distributed account technology. P>
as like as two peas (computer) have identical accounting books, and everyone has the same rights, they will not collapse e to the loss of contact or downtime of a single person. As like as two peas, the data is transparent and everyone can see what changes are in every account. Its very interesting feature is that the data can't be tampered with. Because the system will automatically compare, it will think that the same number of books with the largest number are real books, and a small number of books with different numbers are false books. In this case, it's meaningless for anyone to tamper with his own account book, because unless you can tamper with most nodes in the whole system. If there are only five or ten nodes in the whole system, it may be easy to do so. However, if there are tens of thousands or even hundreds of thousands of nodes and they are distributed in any corner of the Internet, unless someone can control most computers in the world, it is unlikely to tamper with such a large block chain
< H2 > [elements]combined with the definition of blockchain, we think that we must have the following four elements to be called public blockchain technology. If we only have the first three elements, we will consider it as private blockchain Technology (private chain)
1, peer-to-peer network (power equivalence, physical point-to-point connection)
2, verifiable data structure (verifiable PKC system, non tampering database)
3, distributed consensus mechanism (Solving Byzantine general problem, solving double payment)
4 Game design of Nash equilibrium (cooperation is the strategy of evolutionary stability)
combined with the definition of blockchain, blockchain will realize four main characteristics: decentralized, trustless, collective maintenance and reliable database. And the other two will be derived from the four characteristics Features: open source Privacy. If a system does not have these characteristics, it can not be regarded as an application based on blockchain technology
Decentralized: there is no centralized hardware or management organization in the whole network. The rights and obligations of any node are equal, and the damage or loss of any node will not affect the operation of the whole system. Therefore, it can also be considered that the blockchain system has excellent robustnesstrustworthiness: there is no need to trust each other when participating in the data exchange between each node in the whole system. The operation rules of the whole system are open and transparent, and all data contents are also open. Therefore, within the specified rule range and time range of the system, nodes cannot and cannot cheat other nodes
collective maintenance: the data blocks in the system are maintained by all the nodes with maintenance function in the whole system, and these nodes with maintenance function can be participated by anyone
reliable database: the whole system will enable each participating node to obtain a of the complete database in the form of sub databases. Unless more than 51% of the nodes in the whole system can be controlled at the same time, the modification of the database on a single node is invalid, and the data content on other nodes cannot be affected. Therefore, the more nodes and computing power in the system, the higher the data security in the system
Open Source: since the operation rules of the whole system must be open and transparent, the whole system must be open source for the program
Privacy Protection: since there is no need to trust each other between nodes, there is no need to disclose the identity between nodes, and the privacy of each participating node in the system is protected
you mean platform trading. Domestic illegal, international and mostly deceptive, you find the well-known ones. There is a special introction to blockchain network. Remember to be legal, otherwise you can't withdraw cash and it's useless to make money.
(1) distributed ledger, that is, transaction bookkeeping is completed by multiple nodes distributed in different places, and each node records complete accounts, so they can participate in monitoring the legitimacy of transactions, At the same time, they can testify together
different from traditional distributed storage, the uniqueness of distributed storage of blockchain is mainly reflected in two aspects: one is that each node of blockchain stores complete data according to block chain structure, while traditional distributed storage generally stores data in multiple copies according to certain rules. Second, the storage of each node in the blockchain is independent and has the same status, which relies on the consensus mechanism to ensure the consistency of storage, while the traditional distributed storage generally synchronizes data from the central node to other backup nodes[ 8]
no single node can record the account data separately, so as to avoid the possibility that a single bookkeeper is controlled or bribed to record false accounts. In theory, unless all the nodes are destroyed, the accounts will not be lost, so as to ensure the security of the account data
(2) asymmetric encryption and authorization technology, the transaction information stored on the blockchain is public, but the account identity information is highly encrypted, which can only be accessed under the authorization of the data owner, thus ensuring the data security and personal privacy
(3) consensus mechanism is how to reach a consensus among all accounting nodes to determine the validity of a record, which is not only a means of identification, but also a means of preventing tampering. Blockchain proposes four different consensus mechanisms, which are suitable for different application scenarios and achieve a balance between efficiency and security
the consensus mechanism of blockchain has the characteristics of "the minority is subordinate to the majority" and "everyone is equal", in which "the minority is subordinate to the majority" does not completely refer to the number of nodes, but also can be the computing power, the number of shares or other characteristics that can be compared by computers“ "Everyone is equal" means that when the nodes meet the conditions, all nodes have the right to put forward the consensus results first, and then directly recognized by other nodes, and finally may become the final consensus results. Taking bitcoin as an example, the workload proof is adopted. Only when more than 51% of the accounting nodes in the whole network are controlled can a nonexistent record be forged. When there are enough nodes in the blockchain, this is basically impossible, thus eliminating the possibility of fraud.
(4) smart contract, which is based on these trusted and tamperable data, can automatically execute some pre-defined rules and terms. Take insurance as an example. If everyone's information (including medical information and risk occurrence information) is true and reliable, it is easy to carry out automatic claim settlement in some standardized insurance procts
the resolution calls on the idea of bitcoin, but does not directly mention its name. Instead, it calls it "alternative illegal currency". Blockchain technology is the key point, which points out that this technology has the potential to "fundamentally change" the way trust and security are built on online transactions
but in fact, the United States has not taken action to formulate this rule. However, there is a global blockchain alliance R3 in the process of formulating the standard for the use of blockchain. Of course, blockchain is just a technology that can be used by any enterprise. In China, there is a project called decent, which is more avant-garde. It uses blockchain technology to build a decentralized content publishing platform, but it may encounter some problems in China.