Sandbox mechanism of blockchain

1.

Seeing some answers to the debate on the definition of blockchain, I suddenly realize that my answer to this explanation principle has always been directed at bitcoin. There is no specific and unique answer in the instry between the definition of blockchain. Here I first summarize the characteristics of "blockchain" according to the papers I read:

1; Hash chain & quot There are several nodes participating in the system operation (distributed)

3. Reach a consensus on the consistency of basic data (consensus agreement / algorithm) through a certain protocol or algorithm

since bitcoin is currently one of the most typical and influential applications of blockchain, it will be much easier to understand how bitcoin uses blockchain before understanding other forms of blockchain applications

2. Blockchain is a technology, but it is not a single technology, but the result of the integration of a variety of technologies, including cryptography, mathematics, economics, network science and so on. You can think of it as a distributed shared accounting technology, or as a database, but the database is jointly maintained by all nodes in the chain, and each node has an account book. Because the account books of all nodes are consistent, different nodes can trust each other, and there is no doubt about the data, so we all say that the blockchain has realized trust technically. For detailed professional technology, you can consult some professional technology companies, such as Jinbo technology, which focuses on the development of blockchain related procts, professional R & D team and perfect after-sales service, and you can consult by telephone.

3. There are many consensus mechanisms in the blockchain. The advantage of the pow consensus mechanism behind bitcoin, the most influential one, is that it is secure and can not be tampered with. The disadvantage is that it is too slow to process only seven transactions a second

4. Blockchain is a decentralized distributed ledger system, which can be used to register and issue digital assets, property rights certificates, points, etc., and transfer, pay and trade in a point-to-point manner. Compared with the traditional centralized ledger system, blockchain system has the advantages of complete disclosure, tamper proof, multiple payment prevention, and does not rely on any trusted third party
e to the high network delay in peer-to-peer network, the transaction order observed by each node can not be completely consistent. Therefore, the blockchain system needs to design a mechanism to reach a consensus on the sequence of transactions that occur in the same time. This algorithm to reach consensus on the order of transactions in a time window is called consensus mechanism
-- chainknow

5. 1. Pow (proof of work) workload proof
one sentence introction: the more you do, the more you get
2. POS proof of stake
in a word: the more you hold, the more you get< Pbft: practical Byzantine fault tolerance
3. Pbft: practical Byzantine fault tolerance
Introction: it provides (n-1) / 3 fault tolerance on the premise of ensuring the activity and safety< Dbft: Byzantine fault tolerant algorithm authorized by delegated BFT
Introction: dbft mechanism adopted by ant is that bookkeepers are selected by rights and interests, and then bookkeepers reach a consensus through Byzantine fault tolerant algorithm
5. Pool verification pool
is based on traditional distributed consistency technology and data verification mechanism
chainnova is a blockchain company. I feel it's very good. Although I don't know any hash algorithm, I still know a little bit.

6. At present, there are four main types of consensus mechanisms: pow, POS, dpos, pool
1. POW workload proof, which is familiar with mining, calculates a random number that meets the rules through and or operation, that is, obtains the bookkeeping right, sends out the data that needs to be recorded in this round, and stores it together with other nodes in the whole network after verification
advantages: complete decentralization, free access of nodes
disadvantages: bitcoin has attracted most of the computing power in the world, and other blockchain applications using POW consensus mechanism are difficult to obtain the same computing power to ensure their own security; Mining causes a lot of waste of resources; The period of reaching consensus is long, which is not suitable for commercial application.

2. Proof of rights and interests of POS, a mechanism of upgrading consensus of pow; According to the token proportion and time of each node; It can rece the difficulty of mining in equal proportion, so as to speed up the speed of finding random numbers< Advantages: to a certain extent, it shortens the time to reach a consensus
disadvantages: mining is still needed, which does not solve the pain point of commercial application in essence

3. Dpos share authorization certification mechanism is similar to the voting of the board of directors, in which the coin holders cast a certain number of nodes to verify and account on their behalf
advantages: greatly rece the number of participating verification and accounting nodes, which can achieve second level consensus verification
disadvantages: the whole consensus mechanism still depends on token, and many commercial applications do not need token to exist

4. Pool verification pool, which is based on traditional distributed consistency technology and data verification mechanism; It is a consensus mechanism widely used in the instry chain at present.
advantages: it can work without token, and realizes second level consensus verification on the basis of mature distributed consistency algorithms (pasox and raft)
disadvantages: the degree of decentralization is not as good as that of bictin; The multi center business model is more suitable for multi-party participation

it has great advantages in using consensus mechanism to ensure data consistency (the consensus mechanism is first proposed by ripple, and the network transaction synchronization mechanism with data correctness priority. In the consensus network, no matter how the software code changes, if you can't reach a consensus, you can't enter the network, let alone fork)
- - - - - - - -
PS: a little black, although the consensus mechanism can absolutely ensure that there will be no hard bifurcation at any time. However, the disadvantage of this mechanism is obvious, that is, it is much longer than the current bitcoin network to reach a consensus with other nodes. In extreme cases, the consequences of disconnection in ripple consensus mechanism network are also very terrible

it is possible that one day after the power failure in your home, the whole system will no longer be able to reach a consensus with other rippled nodes (in fact, the consensus mechanism requires more than 80% of the nodes to acknowledge your data before your submission will be accepted by other nodes, otherwise it will be rejected by exclusive nodes), Even you can only empty all your 500 GB data and resynchronize to connect to other ripple nodes

so at present, the existing rippled end is not suitable for civil use (if it is commercial, the impact is relatively small. For example, RL's own rippled node is hosted in Amazon cloud data center. If it has no response for a long time, it can make high claims, and there is almost no break in that place except for large disasters). This is one of the aspects RL has always wanted to improve.

7. How to reach a consensus on decentralized networks
in the blockchain system, there is no centralized bookkeeping institution like a bank, so it is very important to ensure the consistency of each transaction on all bookkeeping nodes, that is, to make the whole network reach a consensus. The consensus mechanism solves this problem
at present, the main consensus mechanisms are workload proof mechanism POW and equity proof mechanism POS
POW determines your chances of getting bookkeeping rights by evaluating your workload. The greater the workload, the more likely you will get this bookkeeping opportunity
POS determines your chances of getting bookkeeping rights by evaluating the number and ration of tokens you hold. This is similar to the stock dividend system, holding a relatively large number of shares can get more dividends
the principle of dpos is similar to that of POS, except that some "deputies to the National People's Congress" are selected. The main difference from POS is that the node elects several agents, which are verified and recorded by the agents
with the development of technology, more advanced consensus mechanisms may emerge in the future.

8. If we simplify the description of the operation process of the traditional notarial certificate, it should be like this: the parties apply for notarization - the notary office evaluates the application - confirms the authenticity and legality of the application items - makes, issues and delivers the notarial certificate. The running process of blockchain public certificate is similar. However, the operation mechanism behind the same operation process is not the same. The reason why the public certificate of blockchain is regarded as the Manifesto of the new environment of notarization is that it has made a subversive change to the traditional notarization certificate in the operation mechanism
01, the core operation mechanism of blockchain public certificate
the operation mechanism of blockchain public certificate is composed of two moles: "Notarization management" and "intelligent assistance". After the applicant submits the application, the blockchain notarization system relies on AI technology to audit the identity and information of the applicant. At the same time, the system will review the content of notarial evidence, and then issue a notarial certificate, at the same time on the chain filing. At the same time, the public certificate of blockchain has been formally formed, which immediately meets the online verification needs of users
the core of the operation mechanism of the notarial certificate of the blockchain lies in the application of the blockchain technology. No matter audio, video, photo or document, as long as it is stamped with a time stamp and then put on the chain, it can become an unchangeable and indestructible evidence document
the second important support in the operation mechanism of the notarial certificate of blockchain is the application of artificial intelligence. The application of this technology greatly saves the applicant's application and waiting time, and also greatly improves the speed and accuracy of the notarial office's document confirmation, eliminating the time delay of manual confirmation and possible operational errors<

02, analysis of the characteristics of the operation mechanism of the notarial certificate of blockchain
through the detailed disassembly of the operation mechanism diagram of the notarial certificate of blockchain, it is not difficult to find that compared with the operation mechanism of the traditional notarial certificate, the operation mechanism of the notarial certificate of blockchain has many noteworthy characteristics
the first is synchronization. In the process of generating the public certificate of blockchain, the actions of the applicant and the notary organization are almost synchronous, and the applicant's application and the notary organization's examination, certificate preparation and certificate issuance are almost synchronous. However, in traditional notarization, there is a time interval between the actions of all parties, which is prone to usurpation. Moreover, e to manual operation, a large amount of time cost will be generated, It further causes the delay of the process. The actions of all parties of blockchain notarization are synchronized online, and the action traces and data are generated instantaneously, thus recing the possibility of tampering and ensuring the authenticity and judicial effect of data files
the second is interactivity. In the process of generating the public certificate of blockchain, the actions of the applicant and the notarization institution are interactive - the applicant submits the application, the notarization institution's artificial intelligence audit, the certificate preparation, the certificate issuance, the data archiving, and the applicant's query are carried out alternately. Different from the traditional notarization, the applicant is more in a passive waiting state after submitting the application, which reces the participation of the applicant
dynamic again. In the process of generating the public certificate of blockchain, the evidence file is a dynamic generation process. The process of applying for the notarial certificate is the process of generating the notarial evidence, and this process itself is a part of the notarial certificate. The traditional notarization is that before the notarization, the evidence documents have been basically finalized. What the notary office does is just a process of confirmation and seal, and the dispute prevention function of notarization is weakened

it is precisely because the operation mechanism of the block chain notarial certificate is quite different from that of the traditional notarial certificate, which determines its absolute advantage over the traditional notarial certificate. On the one hand, it meets the people's requirements for efficiency in the digital age; On the other hand, it also strengthens the authenticity and legal validity of notarial documents. Its interactive feature adapts to the Internet era thinking of emphasizing interaction, which makes all parties involved in notarization enter a positive interactive state. Finally, the dynamic nature of the generation of the public certificate of the blockchain greatly gives play to the initiative of the notary organization, rather than passively confirming the existing evidence documents, which can give full play to the original preventive function of the notary.

9. Jinwowo network analysis: 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.