区块链不是去中心化,区块链一定要去中心化吗

⑴ What is blockchain

[Definition]

Blockchain refers to the method of decentralization and trustlessness A technical solution for collectively maintaining a reliable database. This technical solution allows any number of nodes participating in the system to calculate and record all information exchange data in the system over a period of time into a data block (block) through cryptographic algorithms, and generate the fingerprint of the data block for linking ( chain) and check the next data block, all participating nodes in the system jointly determine whether the record is true.

Blockchain is a general term for technical solutions similar to NoSQL (non-relational database). It is not a specific technology. Blockchain technology can be implemented through many programming languages ​​and architectures. . There are also many ways to implement blockchain. Common ones currently include 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 the author who calls himself Satoshi Nakamoto (Satoshi Nakamoto) individual (or group). Therefore, Bitcoin can be regarded as the first application of blockchain in the field of financial payments.

[Popular explanation]

No matter how big the system or how small the website, there is usually a database behind it. So who will maintain this database? Under normal circumstances, whoever is responsible for operating the network or system will maintain it. If it is a WeChat database, it must be maintained by Tencent's team, and Taobao's database must be maintained by Alibaba's team. Everyone must think that this approach is natural, but this is not the case with blockchain technology.

If we imagine the database as a ledger: Alipay, for example, is a typical ledger, and any change in data is an accounting type. We can think of database maintenance as a very simple accounting method. The same is true in the world of blockchain. Everyone in the blockchain system has the opportunity to participate in accounting. The system will select within a period of time, maybe within ten seconds, or maybe ten minutes, to select the person with the fastest and best accounting during this period. This person will do the accounting, and he will combine the changes in the database during this period with Changes in the ledger are recorded in a block. We can imagine this block as a page of paper. After the system confirms that the record is correct, it will chain the data fingerprints of the past ledger to this paper.Then send this piece of paper to everyone else in the entire system. Then the cycle starts over and the system looks for the next person who can do the accounting quickly and well, and everyone else in the system gets a copy of the entire ledger. This means that everyone in this system has exactly the same ledger. This technology is called blockchain technology, also known as distributed ledger technology.

Since everyone (computer) has exactly the same ledger, and everyone (computer) has exactly the same rights, there will be no problem due to a single person (computer) losing contact or going down. The entire system collapses. Since there are exactly the same ledgers, it means that all data is open and transparent, and everyone can see the digital changes in each account. Its very interesting feature is that the data in it cannot be tampered with. Because the system will automatically compare, it will consider the account books with the largest number of the same number as the real account books, and the small number of account books with different numbers as others are false account books. In this case, it makes no sense for anyone to tamper with their own ledger, because unless you can tamper with most of the nodes in the entire system. If the entire system has only five or ten nodes, it may be easy to do, but 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 of the computers in the world , otherwise it would be unlikely to tamper with such a large blockchain.

[Elements]

Combined with the definition of blockchain, we believe that it must have the following four elements to be called a public blockchain technology. If it only has the first three points elements, which we will consider as private blockchain technology (private chain).

1. Point-to-point peer-to-peer network (peer-to-peer power, physical point-to-point connection)

2. Verifiable data structure (verifiable PKC system, non-tamperable database)

3. Distributed consensus mechanism (solve the Byzantine generals problem and double payment)

4. Nash equilibrium game design (cooperation is an evolutionarily stable strategy)
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[Characteristics]

Combined with the definition of blockchain, blockchain will realize four main characteristics: decentralized, trustless, Collectively maintained (Collectively maintained), reliable database (Reliable Database). And the four characteristics will lead to two other characteristics: open source (Open Source) and privacy protection (Anonymity). If a system does not possess these characteristics, it will not be considered to be based on blockchain technologyApplications.

Decentralized: The entire network has no centralized hardware or management organization. The rights and obligations between any nodes are equal, and the damage or loss of any node will not affect it. operation of the entire system. Therefore, the blockchain system can also be considered to have excellent robustness.

Trustless: Each node participating in the entire system does not need to trust each other for data exchange. The operating rules of the entire system are open and transparent, and all data contents are also public. , therefore within the rule range and time range specified by the system, nodes cannot and cannot deceive other nodes.

Collectively maintain: The data blocks in the system are jointly maintained by all nodes with maintenance functions in the entire system, and these nodes with maintenance functions can be participated by anyone.

Reliable Database: The entire system will be divided into databases so that each participating node can obtain a copy of the complete database. Unless more than 51% of the nodes in the entire system can be controlled at the same time, modifications to the database on a single node are invalid and cannot affect the data content on other nodes. Therefore, the more nodes and stronger computing power participating in the system, the higher the data security in the system.

Open Source: Since the operating rules of the entire system must be open and transparent, for the program, the entire system must be open source.

Privacy protection (Anonymity): Since nodes do not need to trust each other, there is no need to disclose their identities between nodes. The privacy of each participating node in the system is protected. protected.

⑵ What is the core content of blockchain

The core content of blockchain is the contract layer
1. Decentralization
This is blockchain The disruptive feature is that there is no central institution or central server, and all transactions occur in the client application installed on everyone’s computer or mobile phone.
Achieve point-to-point direct interaction, which not only saves resources, makes transactions autonomous and simplified, but also eliminates the risk of being controlled by centralized agents.
2. Openness
Blockchain can be understood as a public accounting technology solution. The system is completely open and transparent.
The account books are open to everyone, enabling data sharing and anyone can check the accounts. .
Blockchain is a transparent and shared general ledger. This ledger is open to the entire network. Once you get its public key, you will know how much money is in the ledger. Therefore, any value conversion is completely Anyone in the world who is interested can watch.For you, the conversion is confirmed by miners for you, so it is an Internet consensus mechanism.
3. Irreversible, non-tamperable and encrypted security
The blockchain adopts a one-way hash algorithm. Each newly generated block is strictly advanced in linear order according to time. The irreversibility and irrevocability of time will lead to any Attempts to intrude and tamper with data information in the blockchain can easily be traced, leading to rejection by other nodes. The cost of counterfeiting is extremely high, which can limit related illegal activities.
(2) In addition to decentralization, blockchain further reading:
1. Concept definition
What is blockchain? From a technological perspective, blockchain involves many scientific and technical issues such as mathematics, cryptography, Internet and computer programming. From an application perspective, simply put, blockchain is a distributed shared ledger and database, which has the characteristics of decentralization, non-tampering, full traceability, traceability, collective maintenance, openness and transparency. These characteristics ensure the "honesty" and "transparency" of the blockchain and lay the foundation for creating trust in the blockchain. The rich application scenarios of blockchain are basically based on the ability of blockchain to solve the problem of information asymmetry and achieve collaborative trust and consistent action among multiple subjects [7].
Blockchain is a new application model of computer technologies such as distributed data storage, point-to-point transmission, consensus mechanism, and encryption algorithms. Blockchain is an important concept of Bitcoin. It is essentially a decentralized database.
Two, features
Decentralization. Blockchain technology does not rely on additional third-party management agencies or hardware facilities, and there is no central control. In addition to the self-contained blockchain itself, each node realizes self-verification, transmission and management of information through distributed accounting and storage. Decentralization is the most prominent and essential feature of blockchain.
Openness. The foundation of blockchain technology is open source. In addition to the private information of the transaction parties being encrypted, the data of the blockchain is open to everyone. Anyone can query the blockchain data and develop related applications through the public interface. Therefore, the entire System information is highly transparent.
Independence. Based on consensus specifications and protocols (similar to various mathematical algorithms such as the hash algorithm used by Bitcoin), the entire blockchain system does not rely on other third parties. All nodes can automatically and securely verify and exchange data within the system without the need for any human intervention.
Security. As long as you cannot control 51% of all data nodes, you cannot manipulate and modify network data at will. This makes the blockchain itself relatively safe and avoids subjective and artificial data changes.
Anonymity. Unless required by legal regulations, technically speaking, the identity information of each block node does not need to be disclosed or verified, and information transfer can be carried out anonymously

⑶ What are the advantages of blockchain

The advantages of blockchain are mainly reflected in the following points:
1. Decentralization
Due to the use of distributed computing and storage, there is no centralized hardware or management organization, and the rights and obligations of any node are all are equal, the systemThe data blocks in are jointly maintained by nodes with maintenance functions in the entire system.
2. Openness
The system is open. In addition to the private information of the transaction parties being encrypted, the blockchain data is open to everyone, and anyone can query the blockchain through the public interface. Data and development related applications, so the entire system information is highly transparent.
3. Autonomy
The blockchain adopts consensus-based specifications and protocols (such as a set of open and transparent algorithms) to enable all nodes in the entire system to exchange data freely and securely in a trustless environment. , so that trust in "people" is changed to trust in machines, and any human intervention has no effect.
4. Information cannot be tampered
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, otherwise the database will not be modified on a single node. Modifications are invalid, so the data stability and reliability of the blockchain are extremely high.
5. Anonymity
Since the exchange between nodes follows a fixed algorithm, the data interaction does not require trust (the program rules in the blockchain will judge whether the activity is valid by itself), so the counterparty does not need to Making the other party trust you by disclosing your identity is very helpful for the accumulation of credit.

As above, there are many applications of blockchain now, and it has been applied to various fields, such as GSN in social banking. GSN can effectively reduce financial risks by applying blockchain technology to finance. Because the credit management level of participating market entities will be improved due to the application of blockchain technology, on the other hand, it will also be conducive to the construction and improvement of the entire social credit system.

Secondly, GSN can transform traditional credit management based on experience and system design into a blockchain management model supported by heavy technical means. By introducing GSN, this advanced information management technology, it will help improve credit management. The technological content improves the accuracy and rigor of management.

Finally, GSN can effectively reduce the current high cost of social credit, open up the information islands between credit information, and effectively prevent the loss, leakage or tampering of social credit information. Blockchain has a wider range of application scenarios in building a social credit trust system and promoting digital inclusive credit reporting.

⑷What are the characteristics of blockchain?

There are five main technical characteristics of blockchain, namely: decentralization, information cannot be tampered with, openness and transparency, and collective maintenance. , reliable database. It can be used in many aspects, for example, let’s take a rental agency. In the past, the agency had information about the property and the tenants. Moreover, some unscrupulous agents would change the information at will, just to make money in the middle. More agency fees. If a blockchain is built and applied in the rental field, then the landlord will fill in the property information, and the tenant's information will be filled in by the tenant. Note that once the information isOnce filled in, it cannot be changed twice. So this is equivalent to removing the center of intermediary. Of course, we are just talking briefly. In fact, deploying such a blockchain is also very complicated.

⑸ The technical characteristics of blockchain include: ( ). a Decentralization b Traceability c Openness and transparency d Non-tampering

The technical characteristics of blockchain include decentralization, non-tampering, consensus trust mechanism, openness, anonymity, cross-platform, etc.

6. Cross-platform

Similar to the TCP/IP protocol of the Internet, blockchain can also be regarded as a basic communication protocol. The cooperation of other mechanisms together constitutes the value Internet based on blockchain. Nodes on the blockchain network operate independently based on common algorithms and data structures. They mainly consume computing resources and have nothing to do with the platform. Computing nodes can be deployed on any platform.

It can be said that the characteristics and development of blockchain come from the soil where it was born - the development of Internet technology and the rise of cloud computing and big data.