Huacun data and blockchain

1.

blockchain is a new application mode of distributed data storage, point-to-point transmission, consensus mechanism, encryption algorithm and other computer technologies. Blockchain is an important concept of bitcoin,

in essence, it is a decentralized 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 a batch of information of bitcoin network transactions, Used to verify the validity of its information (anti-counterfeiting) and generate the next block

extended data

most blockchain public chains are limited by scalability. The biggest feature of blockchain technology is decentralization, which requires that all accounts in the network need to deal with the accounting process. Distributed accounting has high security, low misoperation rate, political neutrality and correctness

however, blockchain technology embraces these features at the same time, sacrificing scalability, unable to meet the personalized supervision, and slightly insufficient in protecting data privacy. Moreover, with the increase of the number of ledger, the interaction delay will increase exponentially, that is to say, the more ledger in the blockchain network, the higher the delay

2.

If you want to understand the application of blockchain, you can refer to many books and opinions, such as illustrated blockchain, blockchain: reshaping the economy and the world, blueprint and guide of new economy, and articles of coin'an community, including a detailed understanding of the platform of coin'an community, with great strength

As the name suggests, blockchain is composed of block and chain. It is a new application mode of computer technology such as distributed data storage, point-to-point transmission, consensus mechanism, encryption algorithm and so on. It is a kind of chain data structure that combines data blocks in order according to the time sequence, and it is a secure and reliable distributed account book that can not be tampered with and forged by means of cryptography

in 2008, in his paper bitcoin: a peer-to-peer e-cash system published by Nakamoto, he first proposed the idea of blockchain and encrypted digital currency. Starting from bitcoin, blockchain has become the underlying technology of various digital currencies

Second, the working principle of blockchain:

1. The basic concepts include: (1) transaction: one operation will change the account status once, such as adding a record 2) Block: records the transaction and status data within a specified time, which is a consensus and preservation of the current account status 3) Chain: it is composed of a series of blocks in chronological order, which is the log record of the whole state change. If you understand the working concept of blockchain, it is not difficult to understand its working principle. Suppose there is a distributed data logbook, which can only be added, not deleted or changed. Its structure is a linear chain formed by a series of "blocks" (which is also the source of the name of "blockchain"), and new data must be put into a new block to be added, The maintenance node can propose a new block, but it must go through a certain consensus mechanism to reach an agreement on the final selected block

2. Take bitcoin as an example to see the working principle of blockchain

the block of bitcoin is divided into block head and block body

Core advantages and characteristics of blockchain

1. The verification, accounting, storage, maintenance and transmission of decentralized blockchain data are all based on distributed system structure. There is no centralized hardware or management organization, and the rights and obligations of any node are equal, The data blocks in the system are jointly maintained by the nodes with maintenance function in the whole system. 2. The open and transparent 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. Security blockchain uses 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. 4. Information cannot be tampered with. Once the information is verified and added to the blockchain, it will be stored permanently. Unless more than 51% (almost impossible) 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, and its data interaction does not need trust (the program rules in the blockchain will judge whether the activity is effective or not). Therefore, the counterparties do not need to let the counterparties generate their own trust by disclosing their identities, which is very helpful for credit accumulation

At present, the most popular classification of blockchain is to divide blockchain into public blockchain, private blockchain and consortium blockchain according to different participants

1. Public chain: anyone can participate in the use and maintenance, and can obtain the effective confirmation of the blockchain. Public chain is the earliest blockchain and the most widely used blockchain at present, such as bitcoin blockchain. The information is completely public

if the licensing mechanism is introced, it includes private chain and alliance chain. 2. Private chain: a company or indivial only uses the blockchain technology, enjoys the exclusive write permission of the blockchain, and does not disclose the information. At present, conservative giants (traditional finance) want to experiment with private blockchain, and the application procts of private blockchain are still groping. 3. Alliance chain: it is a blockchain between the public chain and the existing chain, which is jointly controlled by multiple organizations. The use of the chain is managed with authority, which can be controlled by the manager, and also open to others according to the manager's wishes. In addition, according to the different use scenarios and purposes of blockchain, it can be divided into currency chain for the purpose of digital currency, property chain for the purpose of recording property rights, and crowdfunding chain for the purpose of crowdfunding

On May 28, Ma Huateng, CEO of Tencent, proposed the anti-counterfeiting method based on cloud integrated blockchain technology, which is far more efficient than traditional anti-counterfeiting methods. The future anti-counterfeiting verification scenario may only require users to use their mobile phones for simple scanning, and a large number of complete information based on different dimensions can be obtained

take Maotai liquor as an example:

distillery address, proction workshop, operation staff, inspector, delivery time, transportation vehicle information and driver information,

liquor year, raw material source, raw material supplier, storage warehouse number, raw material transportation vehicle and driver information,

all information can be accurately traced, permanently recorded and tampered with

the above information can be easily verified

2. Food safety issues as early as last November, Wal Mart has cooperated with IBM to track the source of food by using blockchain technology, so as to ensure the safety of food and increase the circulation of food to rece costs. For Wal Mart and other large supermarkets, it took a few days to investigate the source of problem food, After using this technology, only one item of proct information is needed to achieve accurate traceability, and important information such as food origin, inspector, supplier, logistics and transportation can quickly find problems in a few minutes. Currently, procts tracked by blockchain include packaging procts from the United States and pork from China

3. Information security

blockchain technology is promoting an information security technology revolution. (1) identity protection PKI is a common public key encryption technology in e-mail, message application, website and other communication applications. However, since the implementation of most PKI, the centralized trusted third party certification authority (CA) is used to issue, activate and store user certificates. Hackers can attack PKI to fake user identity or crack encrypted information

certcoin is the first PKI implementation of blockchain, which comes from MIT, removes the centralized authentication center, and uses blockchain as a distributed ledger for domain name and public key

pomcor company: blockchain PKI implementation path: keep the authentication center, and use blockchain to store the hash value of issued and activated certificates. Users can verify the authenticity of certificates through decentralized and transparent sources, and can also improve the network access performance through local authentication of secret key and signature based on blockchain

(2) data integrity protection

guardtime developed a secret key free signature architecture (Ksi) based on blockchain technology to replace the secret key based data authentication technology. Ksi stores the hash table of the original data and files on the blockchain, runs the hash algorithm to verify other copies, and compares the results with the data stored in the blockchain. Any data tampering will be found quickly because the original hash table is stored in millions of nodes

(3) key infrastructure protection

the "Achilles heel" of the Internet, DDoS has entered the TB era, DDoS is still the simplest weapon for hackers to bring down the big target with low cost, DNS service is the primary target for hackers to carry out large-scale destruction, but blockchain technology is expected to fundamentally solve the problem

The distributed storage of

blockchain makes hacker attacks lose focus. Nebulis is developing a distributed DNS system, which uses Ethereum blockchain and interstellar Internet file system (IPFs, the distributed substitute of HTTP) to register and resolve domain names. The biggest weakness of DNS is caching, which makes DDoS attacks possible. It is also the bane of the centralized government's censorship of social networks and manipulation of DNS registration. A highly transparent and distributed DNS system can effectively prevent any entity, including the government, from arbitrarily manipulating records

(1) digital currency: improve the convenience of currency issuance and use, such as bitcoin and Ethernet in foreign countries, and guorenbao in China

from the use of physical transactions, to physical currency and credit currency, and then to the rise of bitcoin network, more and more people are aware of the distributed ledger blockchain technology behind it, and graally apply it in many scenarios other than digital currency

(2) cross border payment and settlement: realize point-to-point transaction, rece intermediate fees

transfer and payment. At present, the most mature application of blockchain technology is payment and transfer. Blockchain technology can avoid complicated systems, save the process of inter-bank reconciliation and review, and accelerate the settlement speed; Virtual currency can rece transaction costs without the intervention of clearing house. Different countries have different clearing proceres. It takes two or three days for a single remittance to arrive, which is inefficient and accounts for a large proportion of funds in transit. No longer through the third party, through the blockchain technology to form point-to-point payment. By eliminating the link of the third-party institutions, we can make full day payment, real-time payment, withdraw cash quickly and rece the hidden cost, which helps to avoid the capital risk. It is timely and convenient

(3) bills and supply chain financial business: rece human intervention, rece costs and operational risks

value transfer between point-to-point, control and verify physical bills or central system; Intermediaries will be eliminated and human intervention reced. With the improvement of efficiency, financing channels are more unblocked, risks are lower, and multiple parties benefit

(4) securities issuance and Trading: realize quasi real-time asset transfer, accelerate the speed of transaction clearing

the application of blockchain technology can make the process of securities trading more concise, transparent and fast, rece the plication of IT system, and improve the efficiency of market operation. For stocks, blockchain can eliminate paper and pen or electronic form records, rece human errors in trading, and improve the transparency and traceability of trading platform. Citigroup and Nasdaq cooperate to promote blockchain applications

(5) customer credit investigation and anti fraud: rece the cost of legal compliance, prevent financial crimes

the customer information and transaction records recorded in the blockchain help banks identify abnormal transactions and effectively prevent fraud. The technical characteristics of blockchain can change the existing credit reference system, and store the data of customers with bad records in the blockchain when the bank concts "know your customer" (KYC)

equity crowdfunding:

3. The decentralized big data transaction realized on the blockchain can effectively rece the contacts of the original data and fundamentally guarantee the security of the data
in the future, jinwowo will focus on blockchain technology to promote the legal circulation and commercial application of big data.

4. The relationship between blockchain and big data storage is as follows:
first, data security: blockchain makes data flow "at ease"
with its trustworthiness, security and non tamperability, blockchain liberates more data. A typical case is used to illustrate how blockchain promotes the generation of big data for gene sequencing. Blockchain sequencing can use the private key to limit access rights, so as to avoid the legal restrictions on indivial access to gene data, and use distributed computing resources to complete the sequencing service at low cost. The security of blockchain makes sequencing an instrialized solution, realizing global scale sequencing, thus promoting the massive growth of data< Second, data open sharing: blockchain guarantees data privacy
the government has a large number of high-density and high-value data, such as medical data, population data, etc. The opening of government data is the general trend, which will have an inestimable impetus to the development of the whole economy and society. However, the main difficulty and challenge of data opening is how to open data while protecting personal privacy. Data desensitization technology based on blockchain can ensure data privacy and provide a solution for data opening under privacy protection. Data desensitization technology mainly uses hash processing and other encryption algorithms. For example, enigma based on blockchain technology can protect the privacy of data and eliminate information security problems in data sharing by computing data without accessing the original data. For example, employees of a company can safely open the path to access their salary information and jointly calculate the average salary within the group. Each participant can know his or her relative position in the group, but he or she knows nothing about the salaries of other members< The schematic diagram of data hash desensitization processing
3. Data storage: blockchain is a kind of database storage technology that can not be tampered with, full history, strong endorsement
blockchain technology, through all nodes in the network participate in the calculation together, and verify the authenticity of their information to achieve the consensus of the whole network, it can be said that blockchain technology is a specific database technology. So far, our big data is still in a very basic stage. The data based on the consensus of the whole network and the reliable blockchain data are tamperable and historical, which makes the quality of the data gain unprecedented strong trust endorsement, and also makes the development of the database enter a new era< Data analysis: blockchain ensures data security
data analysis is the core of realizing data value. In data analysis, how to effectively protect personal privacy and prevent core data leakage has become the primary consideration. For example, with the application of fingerprint data analysis and the popularization of genetic data detection and analysis, more and more people worry that once personal health data is leaked, it may lead to serious consequences. Blockchain technology can prevent this kind of situation through multi signature private key, encryption technology and secure multi-party computing technology. When the data is hashed and placed on the blockchain, the use of digital signature technology can enable those authorized people to access the data. The private key not only ensures the privacy of data, but also can be shared with authorized research institutions. The data is stored on the decentralized blockchain and analyzed without accessing the original data. It can not only protect the privacy of the data, but also provide it to the global scientific research institutions and doctors for sharing. As the basic health database of all mankind, it will bring great convenience to solve the sudden and difficult diseases in the future
v. data circulation: blockchain protects the rights and interests related to data
for valuable data assets of indivials or institutions, blockchain can be used to register them. Transaction records are recognized, transparent and traceable throughout the network, making clear the source, ownership, use right and circulation path of big data assets, which is of great value to data asset transaction
on the one hand, blockchain can break the threat of intermediary ing data, which is concive to the establishment of a trusted data asset trading environment. Data is a very special commodity, which is essentially different from ordinary commodities. It is mainly characterized by unclear ownership and "being owned after seeing and ing", which also determines that the traditional commodity intermediary transaction method can not meet the needs of data sharing, exchange and transaction. Because the intermediary center has the conditions and the ability to and save all the flowing data, it is extremely unfair to the data procers. This threat can not be eliminated only by commitment, and the existence of this threat has become a huge obstacle to the flow of data. Based on the decentralized blockchain, it can break the threat of ing data in the intermediary center and protect the legitimate rights and interests of data owners
on the other hand, blockchain provides a traceable path, which can effectively solve the problem of data right confirmation. Through multiple nodes participating in the calculation in the network, blockchain can participate in the calculation and recording of data together, and verify the effectiveness of their information. It can not only carry out information anti-counterfeiting, but also provide a traceable path. The transaction information of each block is strung together to form a complete detailed list of transactions. The context of each transaction is very clear and transparent. In addition, when people have doubts about the "value" of a block, they can easily trace back the historical transaction records, and then judge whether the value is correct, and identify whether the value has been tampered or recorded incorrectly
with the protection of blockchain, big data will naturally become more active
the tokens of crowdfunding projects on coin Ying China platform are all developed based on blockchain technology, and relevant information will be recorded on the blockchain.

5. When it comes to blockchain, the first thing you think of is bitcoin

now it can be determined that at least the top 10 Internet companies in China have started this project. In the 2018 China Financial Information Service Development Summit Forum released yesterday, Liang Shidong, vice president of ant financial services group, mentioned that at present, China's financial technology mainly appears in the application layer, and there is still a gap between the underlying technology and developed countries, especially how to give full play to the value of artificial intelligence, cloud computing and blockchain in serving the real economy and preventing risks, It also needs to be explored by all walks of life
therefore, it is possible that blockchain is still a child in China and needs time to develop. After all, we haven't thought of how to use it more effectively, and the technology is not very mature.

the concept of entity blockchain may become the trend of the future society. It's still unknown
at present, bitcoin is the most closely related to blockchain. Want to learn more and more than some news of block chain, you can pay attention to some new media. For example, Sohu, Baijia, mustard circle and so on. Foreign websites, such as CCN and coindesk, all have huge information sources. Hope to adopt

6. That's ten times the survival rate he set. If you lose one, you'll get ten. It's set in the game

7. If you don't understand this, don't do it. It's all virtual things. When the landlord asks questions, it's deceptive. It's obvious that those who advertise on this platform value your principal

8. Big data can be put on the word data, which is generated by various social activities. Blockchain is an underlying technology, just like the Internet. However, it regards the Internet as its own bottom layer and builds a blockchain network on the bottom layer of the Internet. Many people also call it "value Internet"
in terms of the connection, big data can be combined with blockchain technology. For example, blockchain has the characteristics of traceability. When big data packets are traded on the blockchain network, they can see the flow direction in the whole network. Be able to confirm and track the data packet