Storage media and blockchain

1. blockchain technology uses mathematical methods to achieve distributed accounting and solve the trust problem, so as to complete the decentralization, which will bring far-reaching influence in many fields such as communication, finance, Internet of things, government management and so on
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.

2. The information of each block in the blockchain is different, and the generation time and recorded data of each block are different. You can regard the blockchain as a bookkeeping book. Every once in a while, someone will write all the transaction information on the blockchain network to one page of the ledger, page by page, and record all the transactions on the blockchain network in turn according to the time
on the other hand, all nodes (computers in short) participating in the network will store one account book, which is updated in real time. Even if one node fails, the blockchain will not be affected.

3. Cloud computing storage can be used as the lower layer of blockchain. Cloud computing or cloud storage is infrastructure, which can be understood as a new generation of computer (or hard disk), while blockchain can be seen as a business oriented accounting system (or a trusted database) that can be built based on Cloud Computing (cloud storage).

4. One is that each node of the blockchain stores complete data according to the block chain structure. Traditional distributed storage generally divides the data into 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
data nodes can be different physical machines or different instances in the cloud
the above is the difference between the blockchain technology of jinwowo network analysis and the traditional distributed storage, for reference.

5. The difference between code chain and blockchain:
blockchain originates from the underlying technology of bitcoin and is the blockchain technology of Internet. IP is connected by blockchain technology to form distributed accounting. It is not easy to tamper with and decentralize
code chain technology is the code chain technology of the Internet of things, which superimposes the Internet of things IDS one by one in a two-dimensional way to form personal records. The application of "code chain" technology will bring more efficient link forms of "people to people", "people to things" and "things to things"
Introction to code chain:
"code chain" refers to a "two-dimensional code chain" formed by using a smart phone to aim at the "two-dimensional code" and "scan", that is, to "generate a new two-dimensional code containing the scanner's DNA" and access to the "service". The whole process can be traced, supervised and managed
"code chain technology" is the most widely used two-dimensional code "scan" payment technology
code chain technology can realize more efficient link form of people to people, people to things and things to things
Introction to blockchain:
blockchain is an important concept of bitcoin. Blockchain is a series of data blocks generated by cryptography. Each data block contains the information of a bitcoin network transaction, which is used to verify the validity of the information (anti-counterfeiting) and generate the next block
in a narrow sense, blockchain is a kind of chain data structure that combines data blocks in chronological order in a sequential way, and it can not be tampered with and forged by cryptography
broadly speaking, blockchain technology is a new distributed infrastructure and computing paradigm, 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 contract composed of automated script code to program and operate data
the difference between code chain digital currency and blockchain digital currency:
the difference between "code chain digital currency" based on code chain technology and the existing blockchain digital currency is that "code chain digital currency" is based on the control of property rights, and uses "intelligent two-dimensional code" as the medium to transform the contracts of various instry chains into divisible, tradable, transferable, exchangeable Traceable "smart contract" and real right exchange within the code chain alliance. In the code chain monetary system, "intelligent two-dimensional code" means "SGR". That is to say, each commodity corresponds to a "smart QR code", and this "QR code" represents the "special reference property" of the commodity. Through special reference to the exchange of property rights, the exchange of goods (barter) can be realized. This two-dimensional code, which represents "special mention of property rights", can be used as the carrier and payment means of digital currency at the same time, and payment can be completed through "two-dimensional code scanning".

6. 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.

7. Virtual currency does not belong to currency, because it is not a general equivalent and can only buy specific goods, which is more like shopping vouchers.

8. Big data and blockchain are two independent things, which do not have to be used
in fact, only high-level security data can be used for blockchain development, and most companies do not have this requirement. It can be understood that there are so many companies in the world, only a small part needs to use big data technology, and a smaller part needs to use blockchain technology. These two parts can intersect but do not include
for companies that normally use big data, there are non relational databases like HBase, mongodb, hive, Mr, spark and so on in terms of storage and processing, which have nothing to do with blockchain.

9. DGC is really unreliable. It's been 20 days since the withdrawal. I think it's really unreliable. Sorry to die