Blockchain daily

1.

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)

< H2 > [Characteristics]

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 robustness

trustworthiness: 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

2. I can only say that this is an emerging instry. We should not care too much about the immediate gains and losses of interests. We should look at the long term, and opportunities are more important

blockchain technology is only a technical means of recording information, and its main characteristics are decentralization and transparency, which can be applied in any instry. The traditional mode of recording information needs the credit of the recorder to endorse it, and people have to pay for the credit cost. Compared with the traditional way of information recording, blockchain has unique advantages: everyone can record, and everyone has all the recorded information, which also means recing the cost of reputation. The so-called blockchain instry itself is a pseudo proposition, and technical means can be applied to any instry.

3. Let's take Weiyou mall of Wen ecology as an example. The blockchain technology can record the proction, factory manufacturing, May 6th transportation, warehousing, sales and other aspects of the proct on the chain. After users get the proct, they can see the traceability of the proct by scanning the QR code.

4. Blockchain is a public account book. You can't say that your natural gas and chopsticks violate the law, because they are just tools
Chinese Mahjong: the world's earliest blockchain project
first of all, a initiates an application. I want to play mahjong and set up a mahjong Bureau, which is equivalent to creating a block, and this block will be broadcast to B, C, D, a, B, C, C, C, C, C, D, D, D, D, D, D, D, D, D, D, D, D, D, D, D, D, D, D, D, D, D D...
in the process of playing mahjong, the above four people constantly play cards, which can be understood as mining, through what to mine? Mahjong machine can understand the mineralization machine. These four miners are the so-called miners. These four miners collide from 144 mahjong, and any right card can be Hu card. We can understand the 144 mahjong as a series of hash values (numbers). The process of Hu card is called computational power. Until Hu card, it means that the right hash value is collided and you can get a reward, Each person will pay the corresponding chips to C and put them in the blockchain. The reward is bitcoin or other virtual coins
Why do the other three people take the initiative to reward C? That's because these people have automatically reached a consensus that C has indeed won, and everyone has recorded the account, including the family members who are sitting next to buy horses. It's not good to deny it, otherwise when it comes out that the character is not good, no one will play with him again. After all, the circle is very important
when we reached a consensus, we didn't see any intermediary or third party judging that C had won, and the rewards given to C didn't need to be transferred to C through the third party. All of them were direct point-to-point transactions. This process was decentralization. The card players (miners) recorded their own achievements in the first game, and the third team won the first game, After the record is completed, a complete block is generated. But remember, this is only the first round. In the whole blockchain, this is just a node. The first eight rounds are finished, that is, eight nodes (blocks). Eight blocks are connected together to form a complete account book, which is the blockchain. Because everyone has one account book, it is a distributed account book. The purpose is to prevent someone from tampering with records. In the end, it is clear who wins or loses.

5. The "fat" awards include three lists, six awards and one special award. Many blockchain companies have won awards. Among them, the data security exchange platform built by lighttree technology for a Hong Kong listed bank won the best landing scenario award of blockchain in 2019. A Hong Kong listed bank uses the trusted data sharing platform proct of tree of light technology based on blockchain and multi-party security computing technology to achieve the maximum value of data users under the premise of not disclosing data.

6. There are also many apps related to blockchain, such as exchanges, wallets, games, etc. What do you need to know? Only one blockchain app can't provide much information. Relevant blockchain information can be found in cryptography.

7.

According to experts, blockchain can be understood as a distributed public ledger, which is connected by various blocks into a chain. In the traditional bookkeeping system, the bookkeeping right is controlled by the central server

on the "account book" of blockchain, every point in the chain can record information on it, forming a point-to-point accounting system. Therefore, blockchain technology is considered as a decentralized technology

For example, in a village of 100 people, Zhang San bought a cow from Li Si and paid him 10000 yuan. In the past, he had to rely on Zhao Liu, a middleman, to transfer his 10000 yuan to Li Si

with the blockchain system, Zhang San can directly record his 10000 yuan to Li Si's account book, and the transaction information will be transmitted to the whole village, that is, the whole blockchain system, so that other 98 people can see the information. The whole transaction process is recorded by the system, which has the advantage of traceability to prevent the loss of Zhao Liu's account book or Li Si's denial of account

extended data

in 2008, Nakamoto first proposed the concept of blockchain. In the following years, blockchain became the core component of electronic currency bitcoin: as a public account book for all transactions. By using peer-to-peer network and distributed timestamp server, the blockchain database can be managed independently

the blockchain invented for bitcoin makes it the first digital currency to solve the problem of repeated consumption. The design of bitcoin has become a source of inspiration for other applications