What is blockchain consensus mechanism

1. 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

2. 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

3. The so-called "consensus mechanism" is to complete the verification and confirmation of the transaction in a very short time through the voting of special nodes; For a transaction, if several nodes with unrelated interests can reach a consensus, we can think that the whole network can also reach a consensus. More generally speaking, if a Chinese microblog big V, an American virtual currency player, an African student and a European tourist do not know each other, but they all agree that you are a good person, then you can basically conclude that you are not bad
as a data structure that stores data in chronological order, blockchain can support different consensus mechanisms. Consensus mechanism is an important component of blockchain technology. The goal of blockchain consensus mechanism is to make all honest nodes keep consistent blockchain view, and satisfy two properties at the same time:
1) consistency. The prefix part of the blockchain saved by all honest nodes is exactly the same
2) effectiveness. The information released by one honest node will be recorded by all other honest nodes in their own blockchain.

4. 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.

5. POW: proof of work (POW), a simple explanation is a proof to confirm that you have done a certain amount of work. Because the whole process of monitoring work is usually extremely inefficient, and it is a very efficient way to prove that the corresponding workload has been completed through the certification of the work results. For example, in real life, graation certificate, driver's license and so on, are obtained by means of test results. That is to say, how much money you get depends on your effective contribution to mining. Simply understand, the better your computer performance, the more revenue you will get. This is to allocate money according to your workload. Most digital currencies, such as bitcoin, lightcoin, etc., are virtual currencies based on POW mode (the higher the computing power, the longer the mining time, the more coins you get)
pos: POS is a consensus algorithm in the public chain, which can be used as a replacement of pow algorithm. POW is a mechanism to ensure the security of bitcoin, Ethereum and many other blockchains, but POW algorithm is criticized for destroying the environment and wasting power in the process of mining. POS tries to solve these problems by replacing the concept of mining with a different mechanism
POS mechanism can be described as a kind of virtual mining. POS mainly relies on the token in the blockchain itself. In pow, a user may buy a computer for 1000 dollars, join the network to mine and proce new blocks, and get a reward. In POS, users can buy tokens of equal value with us $1000 and put them into the POS mechanism as deposit, so that users have the opportunity to generate new blocks and get rewards. In pow, if users spend $2000 on hardware equipment, they will of course get twice the computing power to mine, thus getting twice the reward. Similarly, if you invest twice as much token as the deposit in the POS mechanism, you have twice as much chance to get the right to generate new blocks.

6. The analysis of Chongqing jinwowo network is as follows:
blockchain is a decentralized distributed ledger system. Due to the high network delay in the 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".

7. Sludge specific resistance is a comprehensive index of sludge filtration characteristics. Its physical meaning is: the resistance of unit mass of sludge in unit filtration area when it is filtered under a certain pressure. The purpose of this value is to compare the filtration performance of different sludge (or the same sludge with different amount of mixture). The larger the sludge specific resistance is, the worse the filtration performance is. The curve showing the relationship between the gas flow rate treated by the adsorption bed and the pollutant concentration in the outlet gas is called breakthrough curve. For details of this concept, please refer to line 9 from the bottom on page 278 of air pollution control engineering, Second Edition, published by higher ecation press~

8. 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.

9.

consensus mechanism , in short, is an algorithm to reach a consensus on the sequence of things in a period of time

on the blockchain, the consensus mechanism is like the law of a country, maintaining the normal operation of the blockchain world. On the blockchain, everyone has an account book that records all transactions on the chain. When a new transaction is generated on the chain, everyone receives this information at a different time. Some people who want to do bad things may publish some wrong information at this time. At this time, one person needs to verify the information received by all people, Finally, publish the most correct information

At present, there are three common consensus mechanisms:

1. Proof of work - Pow is one of the most well-known consensus mechanisms. As a literal explanation, POW means that the more work you do, the more profit you get. The job here is to guess the number, who can guess the only number the fastest, who can be the information publicist

Proof of stake POS is also a kind of consensus proof, which is similar to stock certificate and voting system, so it is also called "stock certificate algorithm". The final information is publicized by the person with the most token

3. Practical Byzantine fault tolerance (pbft) is also a common consensus proof. It's different from the previous two. Pbft is based on calculation, and there is no token reward. All the people in the chain participate in the voting, and when less than (n-1) / 3 nodes oppose, they will get the right to publicize the information