Read the logic and principle of blockchain technology
blockchain refers to the technical solution of collective maintenance of a reliable database through centralization and distrust in the past, and it is a technical way for the whole people to participate in bookkeeping. Previous bookkeeping methods were all centralized and needed centralized intermediary, whether it was traditional government, financial institutions, notarization institutions or emerging e-commerce platform and online payment platform
in economic hypothesis, information is sufficient. In fact, it is precisely because of insufficient information that there are very large intermediaries. The existence of intermediaries increases the transaction cost and raises the transaction threshold. In essence, blockchain technology is a large-scale collaboration tool. It makes direct value transfer possible by using pure technology for the first time, and continues the trend of Internet decentralization and disintermediation. Disintermediated blockchain technology will greatly subvert the information intermediary instry
blockchain technology is the basic technology for building bitcoin data structure and encrypted transmission of transaction information, which realizes the issue and transaction of bitcoin. The core of blockchain technology is that all the current participating nodes jointly maintain the transaction and database, so that the transaction is based on the principle of cryptography rather than trust, so that any agreed parties can directly carry out payment transactions without the participation of a third party
technically, a block is a data structure for recording transactions, reflecting the capital flow of a transaction. In the system, the transaction blocks are connected to form a main chain, and all the nodes participating in the calculation record the main chain or part of the main chain
a block contains the following three parts: transaction information, hash formed by the previous block and random number. Transaction information is the task data carried by the block, including the private keys of both parties, the number of transactions, the digital signature of electronic currency, etc; The hash hash formed by the previous block is used to connect the blocks and realize the sequence of past transactions; Random number is the core of the transaction. All nodes compete to calculate the answer of the random number. The node that gets the answer the fastest generates a new block and broadcasts it to all nodes for updating, so as to complete a transaction.
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 is a distributed account book that can not be tampered with and forged by means of cryptography
broadly speaking, blockchain technology is a new distributed infrastructure and computing method, which uses blockchain data structure to verify and store data, uses distributed node consensus algorithm to generate and update data, uses cryptography to ensure the security of data transmission and access, and uses intelligent contracts composed of automated script code to program and operate data
working principle
blockchain system is composed of data layer, network layer, consensus layer, incentive layer, contract layer and application layer. Among them, the data layer encapsulates the underlying data blocks and related basic data and algorithms such as data encryption and timestamp; 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 issuance mechanism and distribution mechanism of economic incentives; The contract layer mainly encapsulates all kinds of scripts, algorithms and smart contracts, which is the basis of the programmable characteristics of blockchain; The application layer encapsulates various application scenarios and cases of blockchain. In this model, chain block structure based on timestamp, consensus mechanism of distributed nodes, economic incentive based on consensus computing power and flexible and programmable smart contract are the most representative innovations of blockchain technology
Seeing some answers to the debate on the definition of blockchain, I suddenly realize that my answer to this explanation principle has always been directed at bitcoin. There is no specific and unique answer in the instry between the definition of blockchain. Here I first summarize the characteristics of "blockchain" according to the papers I read:
1; Hash chain & quot There are several nodes participating in the system operation (distributed)
3. Reach a consensus on the consistency of basic data (consensus agreement / algorithm) through a certain protocol or algorithm
since bitcoin is currently one of the most typical and influential applications of blockchain, it will be much easier to understand how bitcoin uses blockchain before understanding other forms of blockchain applications
Block is a record in the blockchain, which contains and confirms the transactions to be processed< br />
mining refers to the formation of new blocks through calculation. It is a process in which the supporters of the transaction use their own computer hardware to do mathematical calculation for the network to confirm the transaction and improve the security. Take bitcoin as an example: the transaction supporter (miner) runs bitcoin software on the computer and constantly calculates the complex cryptography problems provided by the software to ensure the transaction. As a reward for their service, miners can get the Commission included in the transaction they confirm, as well as the newly created bitcoin< br />
Peer to peer network is a system that allows a single node to interact directly with other nodes, so that the whole system can operate like an organized collective. Take bitcoin: the network is built in such a way that each user is spreading the transactions of other users. And importantly, banks or other financial institutions are not required as third parties< br />
Hash is a classical technology in cryptography, which transforms the input of any length into the output of fixed length composed of letters and numbers through Hassi algorithm< br />
Digital signature is a mathematical mechanism that allows people to prove ownership< br />
Private key is a secret data block that proves that you have the right to consume e-money from a specific wallet. It is realized by digital signature< br />
Dual consumption refers to the user's illegal attempt to pay e-money to two different payees at the same time, which is one of the biggest risks of e-money< br />
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The origin of blockchain: an underlying technology supporting bitcoin
The concept of blockchain was first proposed in bitcoin: a peer-to-peer electronic cash system by Satoshi Nakamoto in late 2008. In this paper, block chain technology is the basic technology to build bitcoin data structure and transaction information encryption transmission, which realizes the mining and transaction of bitcoin. Nakamoto believes that: first, the mode of using third-party organizations to process information has the inherent weakness of lack of trust between points. In order to guard against their customers, businesses will ask customers for completely unnecessary information, but still can not avoid certain fraud; Second, the existence of intermediaries increases the transaction cost and limits the practical minimum transaction scale; Third, digital signature itself can solve the problem of e-money identity. If the third party support is needed to prevent double consumption, the system will lose value. Based on the above three existing problems, Nakamoto Cong has created bitcoin on the basis of blockchain technology< br />
On January 3, 2009, Nakamoto proced the first bitcoin block in the world, genesis block, and excavated 50 bitcoins< br />
On May 21, 2010, Florida programmers bought $25 worth of pizza coupons with 10000 bitcoin, which gave birth to the first fair exchange rate of bitcoin< br />
In July 2010, the first bitcoin platform was established, with a surge in new users and prices< br />
In February 2011, the price of bitcoin reached US $1 for the first time. Since then, exchange trading platforms with British pound, Brazilian real and Polish zloty have opened< br />
In 2012, ripple released that as a digital currency, it uses blockchain to transfer foreign exchange of various countries< br />
In 2013, bitcoin soared. The U.S. Treasury Department has issued the regulations on the personal management of virtual currency to clarify the definition of virtual currency for the first time< br />
In 2014, the mining machinery instry chain represented by China became more and more mature. In the same year, the U.S. it community realized the cross era innovation significance of blockchain in the digital field< br />
In 2015, the US Nasdaq Stock Exchange launched LINQ, a digital ledger technology based on blockchain, to record trading and issue stocks
the principle of blockchain can be understood clearly from each application case, and the application of blockchain principle is becoming more and more popular. Recently, Citigroup, Mitsubishi UFJ Financial Group, UBS and Deutsche Bank will also apply "blockchain" technology to build a fast, convenient and efficient blockchain Low cost trading system. In addition to the financial field, blockchain technology has also begun to be applied to the protection of intellectual property rights, notarization by lawyers, online games and other fields where there is a need for transparent information disclosure and permanent records.