Structure level of blockchain system

1.

From the perspective of technology and architecture, I will tell you my understanding of blockchain in common language

what is blockchain? In a word, blockchain is a storage system. To be more specific, blockchain is a distributed storage system without an administrator and each node has all the data

What are the common storage systems like

first, how to ensure high availability

the common storage system usually uses "rendancy" to solve the problem of high availability. As shown in the figure above, if the data can be copied into several copies and rendant to multiple places, high availability can be guaranteed. The data in one place is hung, and there is data in other places. For example, the master-slave cluster of MySQL is the same principle, and the raid of disk is also the same principle

two points need to be emphasized in this place are: data rendancy often leads to consistency problems

1. For example, in the master-slave cluster of MySQL, there is actually a delay in reading and writing, which means there is a inconsistency in reading and writing in a short period of time. This is a side effect of data rendancy

The second point is that data rendancy often reces the efficiency of writing, because data synchronization also consumes resources. If you add two slave libraries, the write efficiency will be affected. The common storage system is to use rendancy to ensure the high availability of data

so the second question, ordinary storage system, can write more

the answer is yes, for example, take this graph as an example:

in fact, MySQL can do a master-slave synchronization of al masters, master-slave synchronization of al masters, two nodes can be written at the same time. If you want to do a multi room multi live data center, in fact, multi room multi live data synchronization. What we should emphasize here is that multi-point writing often leads to the consistency problem of writing conflicts. Take MySQL as an example, suppose that the attribute of a table is self incrementing ID, then the data in the database is 1234 now. If one of the nodes writes and inserts a piece of data, it may become 5, and then these 5 pieces of data are synchronized to another master node, Before synchronization, if another write node inserts a piece of data, a piece of data with self incrementing ID of 5 will be generated. Then, after the generation, synchronize to another node, and the synchronized data will conflict with the two local 5's after it arrives, which will lead to synchronization failure and write consistency conflict. This problem will occur in the case of multi-point writing

how to ensure consistency in multi-point writing

the reform "Swan class" gives you more technical work

2. Generally speaking, blockchain system consists of data layer, network layer, consensus layer, incentive layer, contract layer and application layer
among them, the data layer encapsulates the underlying data block and related data encryption and timestamp technologies; The network layer includes distributed networking mechanism, data transmission mechanism and data verification mechanism; The consensus layer mainly encapsulates all kinds of consensus algorithms of network nodes; The incentive layer integrates economic factors into the blockchain technology system, mainly including the issuance mechanism and distribution mechanism of economic incentives; The contract layer mainly encapsulates all kinds of scripts, algorithms and smart contracts, which is the basis of the programmable characteristics of blockchain; The application layer encapsulates various application scenarios and cases of blockchain. In this model, chain block structure based on timestamp, consensus mechanism of distributed nodes, economic incentive based on consensus computing power and flexible and programmable smart contract are the most representative innovations of blockchain technology.

3. 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.

4. Generally speaking, blockchain system consists of data layer, network layer, consensus layer, incentive layer, contract layer and application layer
among them, the data layer encapsulates the underlying data block and related data encryption and timestamp technologies; The network layer includes distributed networking mechanism, data transmission mechanism and data verification mechanism; The consensus layer mainly encapsulates all kinds of consensus algorithms of network nodes; The incentive layer integrates economic factors into the blockchain technology system, mainly including the issuance mechanism and distribution mechanism of economic incentives; The contract layer mainly encapsulates all kinds of scripts, algorithms and smart contracts, which is the basis of the programmable characteristics of blockchain; The application layer encapsulates various application scenarios and cases of blockchain. In this model, chain block structure based on timestamp, consensus mechanism of distributed nodes, economic incentive based on consensus computing power and flexible and programmable smart contract are the most representative innovations of blockchain technology.

5. 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.

6. If your blockchain system refers to a decentralized point-to-point system, its characteristics are as follows:
1. The point-to-point system allows members to join freely without middleman, and nodes can interact freely
2. The point-to-point system can speed up information processing and rece costs by replacing middleman

7. Baite is not recommended

to practice guitar: most of them are basswood panels, some even basswood back panels, which are less than 300 yuan, also known as firesticks (because they are made of the same material as firewood, and the intonation is poor)
entry guitar: most of them are spruce panels, rosewood finger boards, and the back panels are not necessarily. The price is about 1000 yuan, and most of them are 500 yuan or 600 yuan, About 1000 yuan, there are also some elementary Miandan Qin
medium Guitar: most of them are spruce panel, rosewood fingerboard, back side panel, mahogany and fire rosewood. Generally, they are middle end single piano of various series, and some of them are full single (very few), with the price around 3000
high end: all single guitars and spruce veneers are the most popular. The price is four or five thousand or more. There is no upper limit. There are tens of thousands of them, but most people don't need them

tips on guitar selection: http://www.jitatang.com/guitar It is recommended to refer to

no matter where you buy it, you should know some experience to avoid being trapped. Generally, you will be trapped when you go to a piano shop for the first time. The most important two points (you can't hear the timbre and so on):
1. Look at the appearance and choose the log color or black directly Sunset color (the classic three color system), never white, Pink Guitar, that is the above said practice piano grade
2. Check the handle. When the guitar is tuned to the standard pitch, the distance between the string and the fingerboard should be about 3mm (that is, the thickness of a coin) at the 12th point. If you press the string too high, you will feel tired, otherwise it will cause the phenomenon of playing. A good hand feeling is that you can easily press any tone with your left finger without any proct or noise, and you don't feel any effort when you press it horizontally
3. Performance (in fact, you can't see it. You can get what you pay for. It's right to choose the most expensive one in your budget.)

8. 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.

9. Firstly, we need to know that blockchain is a new application mode of computer technology such as distributed data storage, point-to-point transmission, consensus mechanism and encryption algorithm. Secondly, as for the composition architecture of blockchain system, jinwowo Group believes that it is composed of data layer, network layer, consensus layer, incentive layer, contract layer and application layer

1. Data layer: encapsulates the underlying data block and related data encryption and timestamp technologies

2. Network layer: includes distributed networking mechanism, data propagation mechanism and data verification mechanism

3. Consensus layer: it mainly encapsulates various consensus algorithms of network nodes; The incentive layer integrates economic factors into the blockchain technology system, mainly including the issuance mechanism and distribution mechanism of economic incentives

4. Contract layer: it mainly encapsulates all kinds of scripts, algorithms and smart contracts, which is the basis of the programmable characteristics of blockchain; At present, jinwowo in Southwest China has taken the lead in big data research with blockchain as the underlying technology, and also provides big data services with blockchain as the underlying technology

5. Application layer: encapsulates various application scenarios and cases of blockchain. In this model, chain block structure based on timestamp, consensus mechanism of distributed nodes, economic incentive based on consensus computing power and flexible and programmable smart contract are the most representative innovations of blockchain technology

10. There is no fasting will not affect,
after all, you are not checking the amount of sugar or anything,
just checking your antibody to syphilis.