Blockchain technology is a new technology in the Internet world

1. Absrtact: blockchain technology is the underlying technology of bitcoin. Without any centralized organization operation and management, bitcoin has been running very stably for many years (perfectly for seven years), and there has been no problem (no missing account). Therefore, some people have noticed its underlying technology and abstracted bitcoin technology, which is called blockchain technology, Or distributed ledger technology
what is centralization

the so-called centralization means "ownership" or ownership by the company. For example, Tencent's q-coin, which is issued by Tencent, is a kind of centralized electronic currency, including the total amount and the issuing method, is supervised and controlled by Tencent. You can use it, trade and go shopping, but you always have to operate in the framework of Tencent, and the final right of interpretation belongs to Tencent

the issuing mode of bitcoin is preset by the program and encryption algorithm, and runs on multiple nodes all over the world. No one or organization can modify it (everyone has his own account book, so it is impossible for one person to control everyone's account book at the same time. If there is such a technology, why should it be so complicated, If you want to blackmail money into your account, you will be the richest man in the world. There is no one left, And it is not controlled by any single person or organization
take an example: for example, Lao Zhang borrows 100 yuan from Lao Li, but Lao Li is afraid that he will default, so he asks the village head to do notarization and write down the account. This is called centralization. But if you don't find the village head, you can use the loudspeaker to shout in the village: "I Lao Li lent Lao Zhang 100 yuan! Please put it in the account book. "We all put this account in our own account book. This is called decentralization
anyone who transfers money between them will release information through loudspeakers. After receiving the information, everyone will record the transaction in their own account book. With distributed ledgers, it doesn't matter if Lao Zhang or Lao Li's ledgers are lost, because Lao Zhao, Lao Ma, Lao Wang and other families have ledgers

the main advantages of blockchain are that it does not need intermediary participation, the whole process is open and transparent, and the cost is low, and the data security is high

at present, blockchain is in a stage where everyone talks about blockchain, but can't perceive its actual technical charm. Since 2017, it has graally come into our sight, and we have graally realized that bitcoin is more fierce than real estate speculation (the price of mining machinery has skyrocketed! The news is on the screen But I still don't know

so, in which fields can blockchain be applied, what kind of changes will it bring to our future life

the core key: everyone has an account book, everyone has an account book, and the information recorded in each person's account book is consistent and synchronous, and the information is completely transparent. If it is fake, it will be the public enemy of the whole people, which greatly increases the cost of data fraud

core key 2: decentralization, which does not need a central system to manage data, prevents some people from changing data and damages the interests of the majority of people

Application:

1. Account security and privacy protection: currency transfer, exchange, payment system. Blockchain can help prevent data manipulation and fraud, prevent distributed denial of service attacks (DDoS), and effectively protect users' network privacy. Key words: anti counterfeiting, anti-counterfeiting, loan payment

2. Copyright regulation and interest disputes: for example, when a song is downloaded, from the author to the procer and then to the singer, they can get payment in real time through the blockchain, without having to wait for a long time like the traditional way, or even get no reward e to right disputes. Instead of waiting for publishers to provide royalty checks, creators can freely control the process from publishing to payment through blockchain application. Key words: real time receipt, no property dispute

3. Internet of things + artificial intelligence: the intelligent devices in the Internet of things based on the blockchain will be used to monitor the real-time situation of urban infrastructure such as bridges, roads, power grids, etc. the blockchain can connect these intelligent devices together for unified management to help them monitor more efficiently. This will help people better understand how to build a smart city in the future. Key words: unified monitoring, intelligent city

4: proof of existence: in life, once you are asked to prove that you are you, that your mother is your mother, that you have never been married, that the house belongs to you, and so on, things seem very simple. Once it falls on you, it is a great trouble. The application of blockchain technology can perfectly solve the above embarrassment. At that time, all the information that belongs to you will be recorded accurately and can not be tampered with. No one has the right to change it. When the technology develops to a certain stage, birth certificate and marriage certificate may be recorded on the blockchain. Keywords: no keywords

in addition to the application scenarios mentioned above, blockchain technology can also be applied to e-commerce, data storage, logistics and other fields. As long as we grasp the characteristics of blockchain technology, it will become easy to understand.

2.

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

extended data:

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 high

5. 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

3.

From the perspective of technology and architecture, I will tell you my understanding of blockchain in common language

what is blockchain? In a word, blockchain is a storage system. To be more specific, blockchain is a distributed storage system without an administrator and each node has all the data

What are the common storage systems like

first, how to ensure high availability

the common storage system usually uses "rendancy" to solve the problem of high availability. As shown in the figure above, if the data can be copied into several copies and rendant to multiple places, high availability can be guaranteed. The data in one place is hung, and there is data in other places. For example, the master-slave cluster of MySQL is the same principle, and the raid of disk is also the same principle

two points need to be emphasized in this place are: data rendancy often leads to consistency problems

1. For example, in the master-slave cluster of MySQL, there is actually a delay in reading and writing, which means there is a inconsistency in reading and writing in a short period of time. This is a side effect of data rendancy

The second point is that data rendancy often reces the efficiency of writing, because data synchronization also consumes resources. If you add two slave libraries, the write efficiency will be affected. The common storage system is to use rendancy to ensure the high availability of data

so the second question, ordinary storage system, can write more

the answer is yes, for example, take this graph as an example:

in fact, MySQL can do a master-slave synchronization of al masters, master-slave synchronization of al masters, two nodes can be written at the same time. If you want to do a multi room multi live data center, in fact, multi room multi live data synchronization. What we should emphasize here is that multi-point writing often leads to the consistency problem of writing conflicts. Take MySQL as an example, suppose that the attribute of a table is self incrementing ID, then the data in the database is 1234 now. If one of the nodes writes and inserts a piece of data, it may become 5, and then these 5 pieces of data are synchronized to another master node, Before synchronization, if another write node inserts a piece of data, a piece of data with self incrementing ID of 5 will be generated. Then, after the generation, synchronize to another node, and the synchronized data will conflict with the two local 5's after it arrives, which will lead to synchronization failure and write consistency conflict. This problem will occur in the case of multi-point writing

how to ensure consistency in multi-point writing

the reform "Swan class" gives you more technical work

4.

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

on December 2, 2019, the word was selected into the top ten catchwords of "biting words" in 2019

extended data:

Application of blockchain Finance:

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

5.

A: the main application fields of blockchain technology are finance, Internet of things and logistics, public service, digital right, insurance and public welfare

First, in the field of finance,

blockchain has great potential application value in international exchange, letter of credit, equity registration, stock exchange and other financial fields

Second, the Internet of things and logistics

blockchain can also be naturally combined in the field of Internet of things and logistics. Through blockchain, we can rece logistics costs, trace the proction and delivery process of goods, and improve the efficiency of supply chain management

Third, in the field of public service, blockchain is closely related to people's proction and life in the fields of public management, energy and transportation. However, the centralization of these fields also brings some problems, which can be transformed by blockchain

Fourthly, in the field of digital right, through blockchain technology, works can be authenticated to prove the existence of text, video, audio and other works and ensure the authenticity and uniqueness of ownership

In the field of insurance, insurance institutions are responsible for fund collection, investment and claim settlement, and often have higher management and operation costs

Sixth, the data stored on the public welfare field

blockchain is highly reliable and tamperable, which is naturally suitable for social public welfare scenarios. The relevant information in the public welfare process, such as donation project, collection details, fund flow, recipient feedback, etc., can be stored on the blockchain, and can be made transparent and public, which is convenient for social supervision

6. Hello, it is reported that the public platform of SMIC blockchain in Changsha is going to launch blockchain + human resource services recently. We can look forward to how they can do blockchain + human resource applications.