Is Alibaba's blockchain public or private

1.

blockchain includes public blockchain, joint (instry) blockchain and private blockchain. Public chain point-to-point e-cash system: bitcoin, smart contract and decentralized application platform: Ethereum

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 bitcoin network transaction information, Used to verify the validity of its information (anti-counterfeiting) and generate the next block

extended data

according to the different degree of blockchain network centralization, three kinds of blockchains under different application scenarios are differentiated:

1. The blockchain with the whole network open and without user authorization mechanism is called public chain

2. The authorized nodes are allowed to join the network, and the information can be viewed according to the authority. It is often used in the inter agency blockchain, which is called alliance chain or instry chain

3. All the nodes in the network are in the hands of one organization, which is called private chain

alliance chain and private chain are also called licensing chain, and public chain is called non licensing chain

blockchain features

1, decentralization. Blockchain technology does not rely on additional third-party management institutions or hardware facilities, and there is no central control. In addition to the self-contained blockchain itself, each node realizes information self verification, transmission and management through distributed accounting and storage. Decentralization is the most prominent and essential feature of blockchain

2. Openness. Blockchain technology is based on open source. In addition to the private information of all parties involved in the transaction is encrypted, the data of blockchain is open to everyone. Anyone can query blockchain data and develop related applications through the open interface, so the information of the whole system is highly transparent

3. Independence. Based on consensus specifications and Protocols (similar to various mathematical algorithms such as hash algorithm used by bitcoin), the whole blockchain system does not rely on other third parties, and all nodes can automatically and safely verify and exchange data in the system without any human intervention

4. Safety. As long as 51% of all data nodes cannot be controlled, the network data cannot be arbitrarily manipulated and modified, which makes the blockchain itself relatively safe and avoids subjective and artificial data changes

5. Anonymity. Unless there are legal requirements, technically speaking, the identity information of each block node does not need to be disclosed or verified, and the information can be transferred anonymously

2. Alibaba's blockchain is still widely used. Ant financial services, food traceability, digital xiongan, etc. have participated in many blockchain projects. Now blockchain + application is still popular. There is a SMIC blockchain service platform project initiated by Changsha high tech Zone, which is a blockchain application landing project and a blockchain + public service mode, and is recruiting enterprises to join the chain.

3.

Public chain, also known as "public chain", refers to the blockchain that anyone in the world can enter the system at any time to read data, send confirmatory transactions and compete for bookkeeping. The public chain is generally considered to be "completely decentralized", because no indivial or institution can control or tamper with the reading and writing of data in it. In terms of application, blockchain public chain mainly includes bitcoin, Ethereum, super ledger, most counterfeit currencies and smart contracts. The ancestor of blockchain public chain is bitcoin blockchain, which has the following characteristics:

1, open source code

upload the code to GitHub, and everyone can get complete blockchain data by downloading, Accept the test of the public

2, complete decentralization

anyone can become a node, each node is open, everyone can participate in the calculation of the blockchain, any node is not permanent, but phased, and any center is not mandatory for nodes. Anyone can read and send transactions, and transactions can be effectively confirmed on the blockchain. Anyone can participate in the consensus process. The consensus process determines whether a block can be added to the blockchain and the exact current state. Everyone can get financial reward from it, which is proportional to their contribution to the consensus process. These public chains are generally considered to be "completely decentralized"

3. Developing decentralized applications

through this public chain, developers can easily develop centralized applications. Public chain can protect the rights and interests of users from the influence of program developers

4. What is blockchain? Blockchain is a technical solution to collectively maintain a reliable database through centralization and distrust in the past. The concept of blockchain first appeared in a paper "bitcoin: a peer-to-peer e-cash system" written by the founder of bitcoin, Nakamoto, in 2008. In short, blockchain is a kind of public accounting technology, which was born to solve the trust cost in our transactions
what is blockchain? Blockchain technology is a way for the whole people to participate in bookkeeping. There is a database behind all the systems. You can think of the database as a big ledger. So it's very important who keeps this account book. At present, whose system will keep accounts, wechat's account book is Tencent's account book, and Taobao's account book is Ali's account book. But now in the blockchain system, everyone in the system can have the opportunity to participate in bookkeeping. If there is any data change in a certain period of time, everyone in the system can conct bookkeeping. The system will judge the person who has the fastest and best bookkeeping in this period, write the content of his records into the account book, and send the content of the account book to all other people in the system for backup. In this way, everyone in the system has a complete account book. This way, we call it blockchain technology
what is blockchain? For example, in our daily online shopping, the money paid after placing an order for the selected goods will first be paid to the third-party payment platform, and the third-party payment platform will only pay the money to the seller's account after the seller delivers the goods to the buyer to confirm the receipt
when a transaction occurs between the buyer and the seller, the system will broadcast the transaction information between them. The person who receives the message will record the transaction after confirming that the message is correct, that is, the person who receives the message has made a data backup for the transaction
just like Zhang Ergou bought an inflatable doll on the Internet, the system would hold a loudspeaker and shout in the village: "Zhang Ergou bought an inflatable doll"“ After hearing the broadcast, the villagers took out a small notebook and wrote it down. Zhang Ergou bought an inflatable doll. Here, the recorded information is like a data backup for this transaction. Back to the current online shopping, if Zhang Ergou's order problems, Alipay system failure can not record this transaction, then Li Goudan's money is not white. On the blockchain, if there is a problem with the order, because in the early stage, the system broadcast everywhere that Zhang Ergou bought an inflatable doll with a loudspeaker, so countless people recorded the transaction information, and there would be no system failure to record the transaction records
what is blockchain? At present, blockchain technology is very popular, especially in the financial sector. Ant finance, LETV finance, Wanda, Ping'an and Minsheng have successively tested blockchain projects, and eurocrowdfunding is in the forefront of using blockchain technology
blockchain is a large-scale and decentralized economic organization mode realized by a group of technologies
bitcoin is a practical embodiment of blockchain technology, which is more accurate than the former
in fact, whether it's blockchain or bitcoin, people are more concerned about the coin itself, which coin makes more money and how to join it
what is blockchain? Blockchain has attracted wide attention because it has changed the original economic organization mode in many fields. For example, in the process of currency issuance and circulation, cryptocurrency makes the core role of the banking system decline, and the organization mode among the central bank, commercial banks and users has changed significantly; In Ethereum erc20 token system, blockchain has completely changed the organization mode among securities issuers, participants at all levels and regulators. Although it brings some problems, it also improves the efficiency of securities issuance and circulation
people are now exploring the application of blockchain in various fields of economy. In essence, they are looking for new ways to use blockchain to adjust or innovate the original economic organization mode of enterprises, instries and regions, and to rece costs and improve revenue. As an economic organization mode, blockchain can be extended downward to its implementation technology, and upward to its impact on social organization and social consciousness, which makes it easier to understand the complex social impact brought by blockchain.

5.

Blockchain is strictly divided into three types: public chain, private chain and alliance chain. The core difference between these three types of blockchains is the degree of openness or decentralization of access rights. Generally speaking, the higher the degree of decentralization, trust and security, the lower the transaction efficiency

generally speaking, each type of blockchain has its own specific mode and value, which is better than others. As long as the demand is solved, the blockchain is valuable

6. Comparison trading platform, such as bitcoin

7. As a coquettish among entrepreneurs, Lao Ma is committed to internationalizing Ali. Blockchain is now internationally recognized as the foundation of the fourth instrial revolution. He will naturally lay out new fields and make long-term plans for Ali. Although the current technology is not mature enough, but dig chain network and major media reports on this aspect are endless. This shows that the instry has great potential in the future.

8.

Ma Yun: I want to know what bitcoin can bring to the society

at the two sessions, Ma Yun... Oh, sorry, Comrade Ma Yun who doesn't want to wear a red hat didn't attend the two sessions

In November 2017, Alibaba, ant financial services and xiong'an signed a strategic cooperation agreement to build a "digital xiong'an blockchain implementation platform". At present, ant financial services has provided blockchain landing application technology in the rental field in xiong'an. It can be said that xiong'an has become the first pilot field of Ali in the overall implementation project of blockchain technology

9. 1. Alliance chain
the openness and decentralization of alliance chain are limited. Its participants are screened out in advance or specified directly. The read permission of the database may be public, or it may be limited to the participants of the system just like the write permission. Currency exchange of digital currency
2. Public chain
public chain is that every node in the blockchain is open, everyone can participate in the calculation of blockchain, and everyone can download complete blockchain data, also known as blockchain ledger
public chain refers to the process that anyone in the world can read and send transactions, and transactions can be effectively confirmed on the blockchain, and anyone can participate in the consensus process. The consensus process determines whether a block can be added to the blockchain and the exact current state
3. Private chain
202. What is private chain
private chain refers to the blockchain whose write permission is only in the hands of one organization. Read access is either open to the public or restricted to any extent. Related applications include database management, auditing, and even a company. Although in some cases, we hope it can have public auditability, in many cases, public readability is not necessary. It can be said that each of the three chains has its own advantages.

10. Talking about the biggest difference between blockchain and traditional Internet, I think the Internet is a network with countless intermediary nodes and central controllers. From the professional point of view, it is communication technology, it is a seven layer communication network, from the public point of view, it can be divided into Internet hardware layer, Internet application layer. The hardware layer of Internet has been mature for 20 years. Application layer also has a large number of intermediary nodes, such as Alipay, when we pay is based on Ali Alipay database, Tencent QQ currency is based on Tencent's intermediary data storage to ensure that it runs correctly. The blockchain is a new model, which is a peer-to-peer network. No one controls the data in the network. The data is scattered on each node in the network. Some mathematical algorithms are used to ensure the consistency of the data. This design is brand new for communication science.