Blockchain open and transparent ledger image
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 P>
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)
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 robustnesstrustworthiness: 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
the third feature of blockchain assets is decentralized bookkeeping
the transfer you give to others will not be delayed for a few days because the bookkeeping agency is on holiday; Not because the bookkeeping institutions want to make profits, so they have to pay high fees; More will not be because of accounting institutions cheating, and suffer losses
because its bookkeeping is carried out by the whole network. The account book that you transfer to others will not be unified because of the loss of the account book data here or there, because the account book is jointly maintained by the whole network, and every node has a backup. If you transfer 0.5 coins to fire coin Niuniu, you two can look at the record data of the whole network together: whether it has arrived, several confirmed, etc., which is very transparent and fair.
blockchain is a new application mode of distributed data storage, point-to-point transmission, consensus mechanism, encryption algorithm and other computer technologies
this is usually the summary of the professional reports, but what is the specific form
first of all, no matter how large a system or how small a 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
secondly, blockchain technology is also known as distributed ledger technology. 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 person with the fastest and best bookkeeping in 10 seconds or 10 minutes, and the person will record the changes of database and account book in a block
we can think of this block as a piece of paper. After confirming that the records are correct, the system will link the fingerprint of the data in the past account book to this piece of paper, and then send this piece of paper to all other people 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
as like as two peas, each computer has the same rights as the owner, and the whole system will not collapse e to the loss of contact or downtime by a single person.
as like as two peas in the book, it means that all data is transparent and open. 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 is 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 a few nodes in the whole system, it may be easy to do so. But if there are tens of thousands and 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 blockchain
I don't know if I can understand such a popular explanation
bitwindow, a professional website platform providing bitcoin news and information services
1. What the Internet changes is the acquisition and transmission of information, while what blockchain does is the transmission of value
for example, on the Internet, we can easily and quickly generate information and it to any place. All information can be spread efficiently, but some valuable information that can only be transferred but cannot be shared often needs credit endorsement
for example, we can't the payment directly to the other party, but we need to subtract some money from the payment account and add some money to the collection account to complete the payment process. The current Internet protocol does not support the function of value transfer. The current value transfer is not direct transmission. Instead, it is endorsed by a centralized third party, such as Alipay, such as banks.
now these centralized organizations put all the calculation of value transfer in a centralized server, which will certainly involve the participation of people, which will cause many problems, such as some "finite theory" and "opportunistic behavior", which will make the whole behavior less credible. So there is a basic question, how to reach a credit consensus
this is how blockchain technology came into being. It can be said that blockchain can build a pure point-to-point value transfer system. Without the mutual trust of each node, blockchain can ensure the integrity and security of data records in the system, and can be separated from the endorsement of third-party organizations, effectively recing the complexity and risk of transactions
2. It is open and transparent, and can not be tampered with
all data of the blockchain can not be tampered with or deleted, and the information of the whole system is open and transparent. If someone owes you a sum of money, and now the data has been put on the blockchain, if he doesn't want to return it to you and play a rogue with you, you can go to the court to protect your rights through the data forensics on the blockchain, so as to get back your legitimate funds. Because the data on the blockchain is open to the whole network, the users of the whole network will know his rogue behavior, which will greatly increase his credit cost. Dishonesty will make him have an important impact in the next life.
the suggestion is to redo the system, and then find the guardian God to reinforce the system security for you, so as to completely plug the loopholes.
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blockchain technology is a decentralized consensus mechanism to maintain a complete, distributed and tamperable ledger database. It can enable the participants in the blockchain to achieve a unified ledger system without establishing a trust relationship
in the future, blockchain will be applied in any field and bring great impact on human life. Blockchain technology is regarded as one of the main protocols of the next generation of value Internet. Blockchain technology will be useful in any field of proction and life that lacks trust. From digital currency to securities and financial contracts, health care, games, artificial intelligence, intelligent contracts, Internet of things, identity authentication, asset trading, e-commerce, social communication, file storage and other fields can be widely used
in the aspect of medical treatment
when the blockchain technology is used to save the personal medical records, there will be the historical data of personal medical treatment, which can be understood as the electronic medical records on the blockchain. In the future, there will be data for medical treatment or health planning, and the real master of this data is the patient himself, not the hospital or a third-party organization. In addition, these data have strong privacy, and the use of blockchain technology also helps to protect the privacy of patients
payment system
compared with the existing traditional payment system, blockchain technology can avoid the complex system, directly between the two sides of the transaction, does not involve intermediary institutions, even if part of the network is paralyzed, it will not affect the operation of the whole system. This method has the characteristics of low price, fast speed, and no intermediate fees
banking
as a digital, secure and anti-interference account, blockchain realizes the core function of Banking: the safe storage and transfer center of value. Some banks with keen sense of smell in the world have begun to actively plan to join the army of blockchain research and application in order to gain the initiative in the fierce competition in the future
identity authentication of blockchain
blockchain has the feature of being accessible to everyone. Everyone can query the block information in any place with network. The high transparency also makes blockchain full of charm. In the future, ID card and account book are basically not needed, because every identity information can be written into the blockchain. When you need to verify the information, you only need to look it up to find it
election
based on the voting transaction on the blockchain, it can be confirmed that no vote has been modified or deleted, and there will be no improper voting
Real Estate
blockchain technology can change the operation mode of the real estate market. It can combine many complex processes and cases that real estate companies usually deal with, speed up the transaction process, rece fraud, and provide more transparent and secure transactions for each participant. Provides a way to achieve paperless and fast trading needs
securities issuance and trading
the probability of various kinds of errors in general stock and other securities trading is too high, which requires manual correction, thus prolonging the time required for transaction settlement. Through the transaction of distributed ledger, the automation of the whole process can be realized, and the security and efficiency can be improved. The identity and transaction volume of the trading party are recorded on the blockchain in real time, with an open, transparent and traceable system. It is concive to the market maintenance of securities issuers and regulatory authorities, and can rece the occurrence of black box operation and insider trading
in the scenario of relatively closed, multi-party trust problems and carrying value transmission, blockchain has unique technical advantages and also shows unique charm, which has great application imagination space. At the current stage, blockchain is worth exploring in some scenarios.
