Blockchain private chain common chain
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
This is two different concepts. According to different standards, blockchain can be classified into three categories:
& # 8195&# 8195; 1) According to the network scope of blockchain, it can be divided into public chain, private chain and alliance chain
&# 8195; 2) According to the docking type of blockchain, it is divided into single chain, side chain and interconnection chain
&# 8195; 3) According to the display environment of blockchain deployment, it can be divided into main chain and test chain
the main chain can be understood as a formal online and independent blockchain network, while the public chain refers to a blockchain that can be read by anyone, can send transactions and can be effectively confirmed by anyone, and can participate in its consensus process
public chain: open to all, anyone can participate
private chain: open to indivial indivials or entities
alliance chain: open to specific organizations
(1) distributed ledger, that is, transaction bookkeeping is completed by multiple nodes distributed in different places, and each node records complete accounts, so they can participate in monitoring the legitimacy of transactions, At the same time, they can testify together
different from traditional distributed storage, the uniqueness of distributed storage of blockchain is mainly reflected in two aspects: one is that each node of blockchain stores complete data according to block chain structure, while traditional distributed storage generally stores data in 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[ 8]
no single node can record the account data separately, so as to avoid the possibility that a single bookkeeper is controlled or bribed to record false accounts. In theory, unless all the nodes are destroyed, the accounts will not be lost, so as to ensure the security of the account data
(2) asymmetric encryption and authorization technology, the transaction information stored on the blockchain is public, but the account identity information is highly encrypted, which can only be accessed under the authorization of the data owner, thus ensuring the data security and personal privacy
(3) consensus mechanism is how to reach a consensus among all accounting nodes to determine the validity of a record, which is not only a means of identification, but also a means of preventing tampering. Blockchain proposes four different consensus mechanisms, which are suitable for different application scenarios and achieve a balance between efficiency and security
the consensus mechanism of blockchain has the characteristics of "the minority is subordinate to the majority" and "everyone is equal", in which "the minority is subordinate to the majority" does not completely refer to the number of nodes, but also can be the computing power, the number of shares or other characteristics that can be compared by computers“ "Everyone is equal" means that when the nodes meet the conditions, all nodes have the right to put forward the consensus results first, and then directly recognized by other nodes, and finally may become the final consensus results. Taking bitcoin as an example, the workload proof is adopted. Only when more than 51% of the accounting nodes in the whole network are controlled can a nonexistent record be forged. When there are enough nodes in the blockchain, this is basically impossible, thus eliminating the possibility of fraud.
(4) smart contract, which is based on these trusted and tamperable data, can automatically execute some pre-defined rules and terms. Take insurance as an example. If everyone's information (including medical information and risk occurrence information) is true and reliable, it is easy to carry out automatic claim settlement in some standardized insurance procts
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
Since 2018, the blockchain instry has been booming. The exploration and application of blockchain is not limited to the underlying platform. Internet giants and financial giants have strengthened the application of blockchain in finance, public welfare, commodity traceability and other fields, especially in the financial field. The application with blockchain technology as the core has been accelerated
the blockchain instry is in the stage of rapid development. According to the data of in-depth analysis report on business model innovation and investment opportunities of blockchain instry published by foresight Instry Research Institute, , by the end of March 2018, 456 blockchain companies mainly engaged in blockchain business in China, from upstream hardware manufacturing, platform services, security services to downstream instrial technology application services, To ensure the development of the instry investment and financing, media, talent services, companies in various fields have been basically complete
analysis on the trend of the number of newly established companies and financing events in China's blockchain instry from 2013 to 2018, The application scenarios of blockchain have been graally enriched. According to the distribution of instry segments, there are 7 instry application companies, mainly Internet companies (Alibaba, Jingdong, Tencent) used in public welfare and commodity traceability, and innovative financial technology applications evolved by financial enterprises (Ping An, CMB, BOC), such as supply chain finance, bills and transaction clearing
because the blockchain can realize the non tampering of information, the possibility of data falsification is eliminated from the root, especially the financial instry, which has high requirements for real data, will embrace the blockchain more actively
analysis on the development trend of blockchain
Secondly, blockchain has become a new hot spot for innovation and entrepreneurship, and technology integration will expand new application space Thirdly, blockchain will be widely implemented in the real economy in the next three years, and become an important support for the construction of Digital China Fourthly, blockchain creates a new platform economy and opens a new era of sharing economy Fifthly, blockchain accelerates the process of "credible digitization" and drives finance to "move from virtual to real" to serve the real economy Sixth, the blockchain supervision and standard system will be further improved, and the instrial development foundation will continue to be consolidatedin addition, as an emerging technology, there are still many technical difficulties in the application of blockchain in the actual proction environment of the financial instry, such as throughput, scalability, consensus mechanism, privacy and security, manageability, etc
technological innovation such as blockchain is of great significance to the financial instry, which is expected to accelerate the process of "credible digitization" and continue to drive the financial "from virtual to real"
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.
It can be understood as the LAN of Internet bar
a few people use it by themselves, more people use it, and more open people still need license, that is, the alliance chain
there is no need for license at all. Anyone can use the public chain
community blockchain; It is also called alliance chain, which means that the nodes participating in the blockchain are selected in advance, and there are usually good network connections and other cooperative relationships between the nodes; Community blockchain is a practical application scenario of the combination of blockchain and physical goods, such as Domenech jewelry's Maobei mode
Hello, the differences between the two are as above, for reference only, hope to adopt