Upstream level of blockchain

1. blockchain has developed in five stages
1. Germination stage: the real germination stage of blockchain was from 2007 to 2009. In 2008, a Japanese American with the pseudonym of Nakamoto first expounded a new fantasy report on electronic money in the form of a synonym on the cryptography discussion group, and bitcoin came out. As early as 2007, Nakamoto began to explore a series of new technologies to create a new currency. On October 31, 2008, bitcoin white paper was released, and on January 3, 2009, bitcoin system officially began to operate
the main technologies supporting bitcoin system include hash function, distributed ledger, blockchain and asymmetric encryption; It can be seen that these technologies build the initial version of the blockchain, and it can also be said that the blockchain is the underlying technology of bitcoin. During the three years from 2007 to 2009, bitcoin was an experimental stage in which a very small number of people participated, and the real commercial activities had not really started
2. "Geek" niche stage: here, "geek" refers to people who are crazy about Internet technology and take technological innovation as fashion and life. On February 6, 2010, the first exchange of bitcoin appeared. On May 22 of the same year, someone bought two hamburgers with 10000 bitcoins. On July 17 of the same year, the exchange Mt. GOx was established, marking the official inflow of bitcoin into the market. Nevertheless, the only people who can really understand and enter the market to participate in bitcoin trading are geeks who are keen on Internet technology. They discuss bitcoin technology on the forum, mine for bitcoin on their own computers, and then buy and sell bitcoin on Mt. GOx. Now these geeks have become billionaires
3. Market brewing stage: the price of bitcoin was $13 at the beginning of 2013, but on March 18 of the same year, the government of Cyprus closed the bank and stock market e to the financial crisis, which made the price of bitcoin soar, and the highest price rose to $266 in April. On August 20 of the same year, the German government confirmed the currency status of bitcoin. On October 14, China network announced the opening of bitcoin payment channel. In November, the US Senate hearing also confirmed the legitimacy of bitcoin. On November 19, the price of bitcoin rose to US $1242, forming a new high. Nevertheless, the foundation for blockchain to enter the mainstream social economy is not yet available, and the soaring price of bitcoin is only e to over optimistic expectations. The containment of China's banking system, the collapse of Mt. GOx and other events made the price of bitcoin continue to fall. At the beginning of 2015, the price of bitcoin has dropped below $200. From 2013 to the beginning of 2015, the public began to understand bitcoin and blockchain
4. The mainstream period of blockchain: on June 23, 2016, the United Kingdom left the European Union, the fifth nuclear test of North Korea in September, Trump's election in November and other events, the uncertainty of the world's mainstream economy led to the recovery of bitcoin with the function of risk aversion. The market demand was large, and the increase of trading volume made the price of bitcoin soar from $400 in 2016 to $20000 in 2017, The wealth effect of bitcoin and the transaction overflow caused by network congestion of bitcoin have led to the outbreak of other series of virtual currencies, as well as a variety of blockchain applications, resulting in the emergence of a large number of blockchain assets that are 100 times, even 1000 times and 10000 times, which has aroused the crazy pursuit of the world, Subsequently, the Chicago Mercantile Exchange launched bitcoin futures trading, marking that bitcoin has officially entered the mainstream investment proct series, and bitcoin and blockchain have entered the global attention
5. Instry landing stage: after the market frenzy in 2017, the virtual currency and blockchain have been adjusted in terms of market, supervision, cognition, etc. in 2018, returning to rationality. In 2017, many blockchain projects that follow the blockchain technology will graally die out with the cooling of the market, and the projects with real blockchain applications will be initially implemented. 2018 is not only the first year of the blockchain, but also a gold rush period for the blockchain. After the waves wash away the sand, what remains is relatively good gold
from the perspective of the history of blockchain development, blockchain technology is not yet mature and is currently in the growth period. The specific practical application of blockchain is only used in the financial field. It still needs a long way to go to apply blockchain from other instries. However, we should grasp the trend of blockchain and actively learn from the new field of blockchain.

2. There are six hierarchical structures in the blockchain, which are from bottom to top: data layer, network layer, consensus layer, incentive layer, contract layer and application layer
1. Data layer
the data layer is the lowest layer in the six hierarchies of the blockchain. We can understand the data layer as a database, but for the blockchain, this database is a tamperable and distributed database, which is what we call "distributed ledger"
in the data layer, that is, the "distributed ledger", the data information on the blockchain is stored, and the blockchain structure, asymmetric encryption technology, hash algorithm and other technical means of the block are encapsulated to ensure the security of the data in the case of the whole network being open. The specific method is:
in the blockchain network, nodes use consensus algorithm to maintain the consistency of data layer (that is, the distributed database), and use asymmetric encryption and hash algorithm in cryptography to ensure the non usurpation and traceability of the distributed database
This constitutes the bottom data structure of blockchain technology. However, it is not enough to have a distributed database. We also need to let the data information in the database be shared and exchanged. Next, we will introce the upper layer of the data layer - the network layer
Second, network layer
the network system of blockchain is essentially a P2P (point-to-point) network. Point to point means that there is no need for an intermediate link or centralized server to control the system. All resources and services in the network are distributed in the hands of each node, and the transmission of information is also a direct communication between the two nodes. However, it should be noted that P2P
(peer-to-peer) was not invented by Nakamoto, and the blockchain only integrates this technology
therefore, the network layer of blockchain is actually a particularly powerful point-to-point network system. In this system, each node can not only proce information, but also receive information, just like sending e-mail. You can write your own e-mail, and you can also receive the e-mail sent to you by others
in the blockchain network, nodes need to jointly maintain the blockchain system. Every time a node creates a new block, it needs to notify other nodes in the form of broadcast. After receiving the information, other nodes verify the block, and then create a new block on the basis of the block. In this way, the whole network can jointly maintain and update the general ledger of the blockchain system
however, what rules should the whole network follow to maintain and update the general ledger of the blockchain system? This involves the so-called "laws and regulations" (rules), which we will introce next: the consensus layer
Third, consensus layer
in the world of blockchain, consensus simply means that the whole network should maintain and update the general ledger of blockchain system according to a unified and agreed rule, which is similar to the rule of updating data. It is one of the core technologies of blockchain and the governance mechanism of blockchain community to let highly dispersed nodes reach consensus efficiently in the decentralized blockchain network
at present, the mainstream consensus mechanism algorithms include: proof of work of bitcoin (POW), proof of rights and interests of Ethereum (POS), proof of rights and interests of EOS (dpos), etc
we now introce the data layer, network layer and consensus layer. These three layers ensure that there are data, networks and rules for updating data on the network. However, there is no free lunch in the world. How can nodes actively participate in the maintenance of the blockchain system? Here is the incentive layer, which we will introce next: incentive layer< 4. Incentive layer
incentive layer is the so-called mining mechanism, which can be understood as incentive mechanism: you can get as much reward as you contribute to the blockchain system. With this incentive mechanism, the whole network nodes can be encouraged to participate in the data recording and maintenance on the blockchain
mining mechanism and consensus mechanism are actually the same truth. Consensus mechanism can be understood as the company's general rules and regulations, while mining mechanism can be understood as the reward rules for what you do well in the general rules and regulations
just like the consensus mechanism POW of bitcoin, it stipulates that more work pays more. Whoever can find the correct hash value first can get a certain amount of bitcoin reward
and Ethereum's POS stipulates that the older the holder is, the more likely he or she will be rewarded
it should be noted that the incentive layer is generally only available for the public chain, because the public chain must rely on the nodes of the whole network to jointly maintain data, so there must be a set of incentive mechanism to encourage the nodes of the whole network to participate in the construction and maintenance of the blockchain system, so as to ensure the security and reliability of the blockchain system
the blockchain is safe and reliable, and it is not intelligent enough, right? The contract layer we will introce next can make the blockchain system more intelligent
v. contract layer
Contract layer mainly includes various scripts, codes, algorithm mechanisms and smart contracts, which is the basis of block chain programming. What we call "smart contract" is at the contract level
if the bitcoin system is not intelligent enough, the "smart contract" proposed by Ethereum can meet many application scenarios. The principle of the contract layer is to embed the code into the blockchain system, in this way to realize the smart contract that can be customized. In this way, on the blockchain system, once the terms of the smart contract are triggered, the system can automatically execute commands< Finally, the application layer. The application layer is very simple. As the name suggests, it is a variety of application scenarios and cases of blockchain. What we now call "blockchain +" is the so-called application layer. At present, the blockchain applications that have been implemented are mainly various blockchain applications built on
eth, EOS and other public chains. There are more applications of gambling and games, and the real practical applications have not yet appeared.

3. The projects of jinwowo network technology analysis blockchain are divided into three levels:

the top and easiest thing to do is the application layer. I can see two or three such projects every day, accounting for more than 95% of the whole market. But such companies often write a lot of technical things in the white paper. In fact, they also write in vain. This is purely for the purpose of collecting pages, because they don't need to talk about technology at all

the second type is the intermediate operation level, such as quantum chain and ant. This kind of project is similar to the operation procere, called the basic chain, which is used to run the application. This category is relatively small, and the proportion has dropped to less than 5%

the third category is more downward extension and lower level, such as standard chain and arcblock. This kind is even less. It's good to see two or three in a month. And some of them are not necessarily true, because there is really nothing to write about, and all fields are occupied by others, so someone will go in this direction.

4. The hierarchical structure of blockchain
1, data layer / data layer
the data layer mainly describes the physical form of blockchain, which is a chain structure starting from Genesis block on blockchain, including block data, chain structure, random number, time stamp, public and private key data on blockchain, and is the lowest level data structure in the whole blockchain technology
2. Network layer / network layer
the network layer mainly realizes the mechanism of distributed network through P2P technology, and the network layer includes P2P networking mechanism, data dissemination mechanism and data verification mechanism. Therefore, blockchain is essentially a P2P network with automatic networking mechanism, and the communication between nodes is maintained by maintaining a common blockchain structure
3. Consensus layer / consensus layer
consensus layer mainly includes consensus algorithm and consensus mechanism, which enables highly dispersed nodes to reach consensus on the effectiveness of block data efficiently in the decentralized blockchain network. It is one of the core technologies of blockchain and also the governance mechanism of blockchain community. At present, there are at least dozens of consensus mechanism algorithms, including workload proof, rights and interests proof, rights and interests authorization proof, burning proof, importance proof and so on
data layer, network layer and consensus layer are the necessary elements of building blockchain technology. Without any layer, it can not be called a real blockchain technology
4. Incentive layer / activator layer
the incentive layer mainly includes the issuing system and distribution system of economic incentive. Its function is to provide certain incentive measures, encourage nodes to participate in the security verification work in the blockchain, incorporate economic factors into the blockchain technology system, encourage nodes that comply with rules to participate in bookkeeping, and punish nodes that do not comply with rules
5. Contract layer / contract layer
the contract layer mainly includes various scripts, codes, algorithm mechanisms and smart contracts, which is the basis of block chain programming. Embedding the code into the blockchain or token, realizing the smart contract that can be customized, and automatically executing without a third party when certain constraints are met, is the foundation of the blockchain's distrust
6. Application layer / application layer
the application layer of blockchain encapsulates various application scenarios and cases, which are similar to applications on computer operating system, portals on Internet browsers, search engines, e-malls or apps on mobile phones. The blockchain technology applications are deployed on Ethereum, EOS and qtum, and are implemented in real life scenarios. The future programmable finance and programmable society will also be built on the application layer
incentive layer, contract layer and application layer are not necessary factors for each blockchain application, and some blockchain applications do not completely include the three-tier structure.

5. Aggregation chain refers to the innovative introction of "alliance chain + cross chain + public chain" aggregation chain technology architecture on the basis of long-term accumulated alliance chain technology, so as to realize the efficient, safe and low-cost flow of data and assets, and then practice the historical mission of enabling distributed economy.

6. Mine pool refers to:
as the computing level of the whole bitcoin network continues to rise exponentially, a single device or a small amount of computing power can not get the block reward provided by bitcoin network
after the computing power of the whole network has been improved to a certain extent, the low probability of getting rewards has prompted some geeks on "bitcoin talk" to develop a method that can combine a small amount of computing power and operate jointly. The website established in this way is called "mine pool"
extended data:
the existence of the mine pool reces the difficulty of mining bitcoin and other virtual digital currencies, reces the threshold of mining, and truly realizes the concept of bitcoin mining that everyone can participate in
but its disadvantages are also very obvious, because computing power is connected to the mine pool. As a mine pool, it will have a huge amount of computing power resources. In the bitcoin world, computing power represents the bookkeeping right, and computing power is everything. If the computing power of a single mine pool reaches more than 50%, it will be easy to launch 51% attacks on bitcoin and other similar virtual digital currencies, The consequences are very terrible:
the mine pool can make the mine pool with 49% of the remaining computing power have no harvest, instantly quit the competition and go bankrupt. The mine pool's computing power exceeds 50%. If 51% attack is launched, it will easily occupy all the effective computing power of the whole network
source of reference: network mine pool

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8. There is no way to sell a large amount of sealed down limit. Anyway, you can only hang up the down limit every day to see if you have paid for it.