区块链的六大层级结构是什么,区块链的六大层级结构包括

⑴ What are the three levels of blockchain technology?

Jinwowo Network Technology analyzes blockchain projects at three levels:

The easiest thing to do at the top is the application layer. I see two or three such projects every day, accounting for more than 95% of the entire market. But this kind of company often writes a lot of technical stuff in the white paper. In fact, it is written in vain. This is purely to make up for the number of pages, because it does not need to talk about technology at all.

The second category is at the intermediate operational level, such as Quantum Chain and Xiaoyi. Such a project is similar to an operating program, called a basic chain, and is used to run applications. This type is relatively small, and the proportion suddenly dropped to less than 5%.

The third category extends downwards and is at a lower level, such as standard chains and arcblock. There are even fewer of these, and it’s good to see two or three a month. And some of them may not be true, because there is really nothing to write about, and all fields are occupied by others, so someone will edit them in this direction.

⑵ Six core algorithms of blockchain technology

Six core algorithms of blockchain technology
Blockchain core algorithm 1: Byzantine Agreement
The story of Byzantium goes something like this: The Byzantine Empire has huge wealth, and its 10 neighboring countries have been around for a long time. However, Byzantium’s high walls are towering and impregnable, and no single neighbor can successfully invade. Any invasion by a single neighbor will fail, and it is also possible that it will be invaded by 9 other neighbors. The Byzantine Empire's defensive capabilities were so strong that at least half of its ten neighbors had to attack at the same time to be able to break through. However, if one or several of the neighbors agree to attack together, but betrayal occurs during the actual process, then the invaders may all be annihilated. So each party acted cautiously and did not dare to trust its neighbors easily. This is the Byzantine Generals Problem.
In this distributed network: each general has a message ledger that is synchronized with other generals in real time. The signature of each general in the ledger can be used to verify the identity. If any messages are inconsistent, you can know which generals the messages are inconsistent with. Even if there is inconsistent information, as long as more than half agree to attack, the minority obeys the majority, and a consensus is reached.
Thus, in a distributed system, although there are bad guys, bad guys can do anything (not restricted by the protocol), such as not responding, sending error messages, sending different decisions to different nodes, and combining different wrong nodes. Get up and do bad things, etc. However, as long as most people are good people, it is entirely possible to achieve consensus in a decentralized manner
Blockchain Core Algorithm 2: Asymmetric Encryption Technology
In the above Byzantine Agreement, if one of the 10 generals Several messages initiated at the same time will inevitably cause chaos in the system, causing each to have its own attack time plan, making it difficult to act in a consistent manner. Anyone can initiate an offensive message, but who will send it out? In fact, this only requires adding a costThat's it, that is: only one node can propagate information within a period of time. When a node sends a unified attack message, each node must sign and stamp the message from the initiator to confirm their identity.
It seems today that asymmetric encryption technology can completely solve this signature problem. The asymmetric encryption algorithm uses two different keys for encryption and decryption. These two keys are the "public key" and "private key" that we often hear. Public keys and private keys generally appear in pairs. If a message is encrypted with a public key, the private key corresponding to the public key is required to decrypt it; similarly, if a message is encrypted with a private key, the public key corresponding to the private key is required to decrypt it.
Blockchain Core Algorithm Three: Fault Tolerance Issue
We assume that in this network, messages may be lost, damaged, delayed, sent repeatedly, and the order received is inconsistent with the order sent. In addition, the behavior of nodes can be arbitrary: they can join and exit the network at any time, they can discard messages, forge messages, stop working, etc. Various human or non-human failures may also occur. Our algorithm provides excellent fault tolerance for a consensus system composed of consensus nodes. This fault tolerance includes both security and availability, and is applicable to any network environment.
Blockchain core algorithm 4: Paxos algorithm (consensus algorithm)
The problem solved by the Paxos algorithm is how a distributed system can reach agreement on a certain value (resolution). A typical scenario is that in a distributed database system, if the initial state of each node is consistent and each node performs the same sequence of operations, then they can finally obtain a consistent state. In order to ensure that each node executes the same command sequence, a "consistency algorithm" needs to be executed on each instruction to ensure that the instructions seen by each node are consistent. A general consensus algorithm can be applied in many scenarios and is an important issue in distributed computing. There are two models for node communication: shared memory and message passing. The Paxos algorithm is a consensus algorithm based on the message passing model.
Blockchain Core Algorithm Five: Consensus Mechanism
The blockchain consensus algorithm is mainly proof of work and proof of equity. Taking Bitcoin as an example, in fact, from a technical point of view, PoW can be regarded as reused Hashcash. Generating proof of work is a random process in terms of probability. To mine a new confidential currency, when generating a block, all participants must agree, and the miner must obtain PoW proof of work for all data in the block. At the same time, miners must constantly observe and adjust the difficulty of this work, because the network requirement is to generate a block every 10 minutes on average.
Blockchain Core Algorithm 6: Distributed Storage
Distributed storage is a data storage technology that uses the disk space on each machine through the network and combines these dispersed storage resources into a virtual Storage devices, data are stored dispersedly in every corner of the network. Therefore, distributed storage technology does not store all the data on every computer.Instead of the whole data, the data is divided and stored in different computers. It's like storing 100 eggs, not in the same basket, but in different places. The total sum is 100.

⑶ What is the model architecture of blockchain?

Blockchain technology is not a single innovative technology, but the result of integrated innovation of multiple technologies. Its essence is a weak center. , self-trusting underlying architecture technology. Compared with traditional Internet technology, its technical principles and model architecture are a major innovation. Here, we will analyze the basic technical model of blockchain.

Model diagram

The blockchain technology model includes data layer, network layer, consensus layer, incentive layer, contract layer and application layer from bottom to top. . Each layer has a core function, and different layers cooperate with each other to jointly build a decentralized value transmission system

The data layer is the lowest level interpretation architecture of the blockchain, which uses public and private keys. The combined asymmetric encryption technology uses hash functions to ensure that information is not tampered with, and also uses chain structure, timestamp technology, Merkle tree and other technologies to process data blocks, so that the old and new blocks can be Mutual links and mutual verification are the basis for the safe and stable operation of the blockchain.

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⑷ The hierarchical structure of the blockchain (what is Layer0/1/2 of the blockchain)

The hierarchical structure is the basis for the data processing and operation of the blockchain.

In order to find a scalability solution for the blockchain, the blockchain referred to in the academic research field (usually in papers) is divided into three layers: Layer0, Layer1 and Layer2.

Generally, the blockchain system is mainly divided into six layers: application layer, incentive layer, consensus layer, network layer and data layer, which are mainly reflected in the early Bitcoin system. With the emergence of smart contracts, a contract layer was added between the application layer and the incentive layer, mainly reflected in the Ethereum system.

The content of each layer is shown in the figure above, but the technologies used in different specific systems may be different. For example, the consensus layer mainly completes the consensus between nodes, except for the workload proof. Mechanism (Proof of Work) andMethods such as Proof of Stake and Byzantine Fault Tolerance (BFT).

The data layer, network layer, and consensus layer constitute the underlying foundation of the blockchain level. They are also three essential elements of the blockchain. Without any one of them, it cannot be called a real blockchain technology.

The hierarchical structure of the blockchain corresponds to the OSI system 7-layer model and TCP The comparison under the /IP 4-layer model is shown in the figure below.

If we focus on the four layers of TCP/IP, especially the "application layer" above, we will see that it is possible to distinguish Blockchain separates the application layer that originally focused only on information transmission into a new layer dedicated to value transfer. Therefore, we can think of the four layers of TCP/IP as split into five layers, and treat the blockchain as TCP /Layer of IP: Value layer.

It is generally believed that Bitcoin, Ethereum, and EOS are representatives of blockchain 1.0, 2.0, and 3.0. It is also interesting to look at their layers:< br />
From Bitcoin to Ethereum, a contract layer was added. From Ethereum to EOS, due to the adoption of DPOS, the incentive layer was actually merged into the consensus layer. EOS added two layers: ① Tool layer, Make it easier to develop applications on it; ② Ecological layer, it is positioned as an open source software, so others can use its open source software to establish industry chains and domain chains.

Xu Zhong, Zou Chuanwei Wrote a central bank working paper, discussing blockchain from the perspective of economics, trying to give a Token paradigm. Among them, they actually gave a layered model, this time it is internal and external layering: the inner layer is consensus , is further divided into: Token, smart contract, consensus algorithm; at the boundary of consensus and blockchain, it is other information in the blockchain; outside the boundary of blockchain, it is the Internet and the physical world.

In order to improve performance, some systems actually useDistributed networks are also layered. That is, not all nodes are equal.
For example, the following is the layering of EOS.

In order to make blockchain useful, some people are discussing it from other perspectives. Zhu Feng of ENChain.Asia proposed the "Seven-layer Self-Organizing Business Model" in the BAO white paper. This model was quoted in the "Model and Practice of Token Economy" (0.2) report as the "Seven-layer Self-Organizing Business Model" Model".

However, it should be noted that the "incentive layer" here is similar to the incentive layer we usually call blockchain, but it is different. When we discussed the incentive layer before, we often discussed it from the perspective of the native tokens of the public chain, while the incentive layer here is discussed at the pass level.

In a December 2018 report "Construction and Analysis of the Four-Layer Application Model of Blockchain", Huobi Research Institute gave a four-layer application model, which is very interesting:< br />
References:
1. Ten years of blockchain: various layers
http://www.360doc.com/content/18/1211/10/ 53358875_800866301.shtml
2. How much do you know about the six hierarchical structures of blockchain? - Zhihu
https://zhuanlan.hu.com/p/98126049
3. Introduction to the six hierarchical structures of blockchain - Blockchain - Electronic Enthusiast Network
http ://www.elecfans.com/blockchain/1138839.html

⑸ What is the six-layer model of the blockchain?

The blockchain has a total of six levels of structure. These six The hierarchical structure from bottom to top is: data layer, network layer, consensus layer, incentive layer, contract layer, and application layer.
1. Data Layer
The data layer is the lowest layer of the six-level structure of the blockchain. We can understand the data layer as a database, but for blockchain, this database is an immutable and distributed database, which is what we call a "distributed ledger".
On the data layer, that is, on this "distributed ledger", the data information on the blockchain is stored, encapsulating the blockchain structure of the block, asymmetric encryption technology, hash algorithm and other technologies Means to ensure the security of data when it is disclosed to the entire network. The specific approach is:
On the blockchain network, nodes use consensus algorithms to maintain the consistency of data in the data layer (that is, this distributed database), using asymmetric encryption and hash algorithms in cryptography. , to ensure that this distributed database cannot be tampered with and is traceable.
This constitutes the lowest level data structure in blockchain technology. However, it is not enough to have a distributed database. The data information in the database also needs to be shared and exchanged. Next, we introduce the upper layer of the data layer - the network layer.
2. Network layer
The network system of the 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. Everything in the network Resources and services are allocated to each node, and information can be transmitted directly between the two nodes. However, it should be noted that P2P
(peer-to-peer) was not invented by Satoshi Nakamoto. Blockchain just incorporates this technology.
So, the network layer of the blockchain is actually a particularly powerful peer-to-peer network system. In this system, each node can both produce and receive information, just like sending emails. You can write your own emails or receive emails sent to you by others.
On the blockchain network, nodes need to jointly maintain the blockchain system. Whenever a node creates a new block, it needs to notify other nodes in the form of broadcast, and other nodes receive After receiving the information, the block is verified, and then a new block is created based on the block. In this way, the entire network can jointly maintain and update the general ledger of the blockchain system.
However, what rules should the entire network follow to maintain and update the general ledger of the blockchain system? This involves the so-called "laws and regulations" (rules), which is what we will introduce next: the consensus layer.
3. Consensus Layer
In the world of blockchain, consensus, simply put, means that the entire network must maintain and update the general ledger of the blockchain system according to a unified and agreed-upon rule. Similar to the rules for updating data. Allowing highly dispersed nodes to efficiently reach consensus in a decentralized blockchain network is one of the core technologies of the blockchain and is also the governance mechanism of the blockchain community.
The current mainstream consensus mechanism algorithms include: Bitcoin’s Proof of Work (POW), Ethereum’s Equity CertificateMing
(POS), EOS’s Delegated Proof of Equity (DPOS), etc.
We have now introduced the data layer, network layer, and consensus layer. These three layers ensure that there is data and network on the blockchain, and there are rules for updating data on the network. However, there is no free lunch in the world. How to make it happen? Nodes can actively participate in the maintenance of the blockchain system. This involves incentives, which is what we will introduce below: the incentive layer.
4. Incentive layer
The incentive layer is the so-called mining mechanism. The mining mechanism can actually be understood as an incentive mechanism: how much you contribute to the blockchain system, you can get as many rewards as you want. Using this incentive mechanism, nodes across the entire network can be encouraged to participate in data recording and maintenance on the blockchain.
The mining mechanism and the consensus mechanism are actually the same. The consensus mechanism can be understood as the company's general rules and regulations, and the mining mechanism can be understood as, within this general rules and regulations, what you have done can What kind of reward you get, this kind of reward rules.
Just like Bitcoin’s consensus mechanism PoW, its stipulation is that the more work you do, the more you gain. Whoever can find the correct hash value first can get a certain amount of Bitcoin rewards;
And Ethereum PoS stipulates that the longer who holds the currency, the greater the probability of receiving rewards.
It should be noted that the incentive layer is generally only available in public chains, because public chains must rely on nodes across the entire network to jointly maintain data, so there must be such an incentive mechanism to encourage nodes throughout the network to participate in the blockchain system. Construction and maintenance to ensure the security and reliability of the blockchain system.
The blockchain is safe and reliable, but it is not smart enough, right? The contract layer we will introduce below can make the blockchain system more intelligent.
5. Contract Layer
The contract layer mainly includes various scripts, codes, algorithm mechanisms and smart contracts, and is the basis for blockchain programmability. The "smart contract" we are talking about belongs to the contract layer.
If the Bitcoin system is not smart enough, then the "smart contracts" proposed by Ethereum can meet many application scenarios. The principle of the contract layer is mainly to embed code into the blockchain system and use this method to implement customizable smart contracts. In this way, on the blockchain system, once the terms of the smart contract are triggered, the system can automatically execute the order.
6. Application Layer
The last is the application layer. The application layer is very simple. As the name suggests, it is the various application scenarios and cases of blockchain. The "blockchain+" we are talking about now is the so-called application layer. The blockchain applications that have been implemented so far are mainly various blockchain applications built on public chains such as ETH and EOS. There are many gambling and game applications, and truly practical applications have not yet appeared.

⑹ What are the different types of blockchains

The different types of blockchains are as follows

1. Divided by degree of openness: public chain,Alliance chain, private chain

2. Divide by application scope: basic chain, industry chain
There is a saying that currency is about consensus, and chain is about ecology.

3. Divide by original program: original chain, forked chain
This division may be more niche, and maybe there is such an understanding

Four , divided according to the degree of independence: main chain, side chain
There is another way to divide the blockchain according to whether the blockchain is independent enough.

5. Division by hierarchical relationship: parent chain, sub-chain
The last division method is also relatively niche, and let’s give a simple definition.

⑺ What are the blockchain technology frameworks?

The current mainstream blockchain architecture contains six levels: network layer, data layer, consensus layer, incentive layer, contract layer and application layer. The positions of the data layer and the network layer are reversed in the figure, and their main uses will be detailed in the next section.
Network layer: The essence of the blockchain network is a P2P (Peer-to-peer) network. The resources and services in the network are scattered on all nodes. The transmission of information and the implementation of services are directly between the nodes. It can be carried out in a short period of time without the intervention of intermediate links and servers. Each node both receives and generates information. The nodes synchronize information by maintaining a common blockchain. When a node creates a new block, it notifies other nodes in the form of broadcast, and other nodes receive the information. The block is then verified and a new block is created based on the block, thereby achieving the role of the entire network jointly maintaining an underlying ledger. Therefore, the network layer will involve the design of P2P network, propagation mechanism, verification mechanism, etc. Obviously, these designs can affect the confirmation speed of block information. The network layer can be used as a research direction in the scalable solution of blockchain technology;
Data layer: The underlying data of the blockchain is a block + linked list data structure, which includes data blocks, chain structures, timestamps, hash functions, Merkle trees, asymmetric encryption and other designs. Among them, data blocks and chain structures can be used as improvement directions for data layer research in the scalable solution of blockchain technology.
Consensus layer: It is the basis for highly dispersed nodes to achieve rapid consensus on the validity of block data. The main consensus mechanisms include POW (Proof Of Work) and POS (Proof of Stake). Mechanism), DPOS (Delegated Proof of Stake Delegated Proof of Stake Mechanism) and PBFT (Practical Byzantine Fault Tolerance), etc., which have always been the highlight of the scalable solutions of blockchain technology.
Incentive layer: It is the mining mechanism that everyone often talks about. It is used to design a certain economic incentive model and encourage nodes to participate in the block.Chain security verification work, including the design of issuance mechanism, distribution mechanism, etc. This level of improvement does not seem to be directly related to blockchain scalability.
Contract layer: mainly refers to various script codes, algorithm mechanisms, smart contracts, etc. Strictly speaking, this layer is missing in the first generation of blockchains, so they can only conduct transactions and cannot be used in other fields or perform other logical processing. The emergence of the contract layer makes it possible to use blockchains in other fields. has become a reality. This part of Ethereum includes two parts: EVM (Ethereum Virtual Machine) and smart contracts. Improvements at this level seem to provide potential new directions for blockchain scalability, but there seems to be no direct connection in structure
Application layer: It is the display layer of the blockchain, including various application scenarios and cases. . For example, Ethereum uses truffle and web3-js. The application layer of the blockchain can be the mobile terminal, the web terminal, or it can be integrated into the existing server, and the current business server is regarded as the application layer. Improvements at this level seem to provide potential new directions for blockchain scalability, but there does not seem to be a direct connection in structure.
The Xueshuo Innovation Blockchain Technology Workstation under Lianqiao Education Online is the only approved "Blockchain Technology Professional" pilot of the "Smart Learning Workshop 2020- Xueshuo Innovation Workstation" launched by the School Planning, Construction and Development Center of the Ministry of Education of China. workstation. The professional base is based on providing students with diversified growth paths, promoting the reform of the training model integrating professional degree research, production, and research, and building an applied and compound talent training system.

⑻ What components should the DAC chain have?

Technical level, the structure of the blockchain. There are multiple blocks on a blockchain, and each block includes a block header and a block body. The block header mainly includes the version number, the hash value of the previous block, timestamp, random number, target hash, and Merkle root; the block body contains the ledger information recorded through the Merkle tree. This mainly shows the technical architecture of the blockchain principle. Next, it mainly introduces the organizational structure and levels. When blockchain technology was first proposed, the architecture was usually divided into six layers, namely data layer, network layer, consensus layer, incentive layer, contract layer and application layer, which was the early architecture diagram of blockchain technology.
Data layer: The data layer is the basic layer, whose function is to collect, record and store urban public safety big data. The block header encapsulates information such as timestamp, root hash value, version number, proof of work, etc. The block body contains public security transaction records calculated using hash algorithm, Merkle tree, asymmetric encryption and other technologies. The password of this layer Learning technologies and operating rules can ensure the security and integrity of public safety big data.
Network layer: As a working mechanism layer, the network layer allows governance entities to jointly participate in the dissemination, verification and accounting of data blocks, and maintains the update and maintenance of public safety big data.
Consensus layer: The consensus layer mainly includes various consensus algorithms, aiming to allow government departments, private units, the public and other governance entities to reach consensus and establish a trust network in the distributed system, therebyMaintaining the effectiveness of public safety big data.
Incentive layer: The function of the incentive layer is that each consensus subject can receive corresponding incentives in the process of collectively maintaining the blockchain system, so that each subject can not only safeguard its own interests, but also ensure the validity and timing of the blockchain data. sex.

Contract layer: The contract layer needs to be designed in the national institutional environment. Its smart contract is a computer digital agreement that each subject has always followed. It can formulate contract rules based on the logic and process of governance, and conduct public activities spontaneously. Secure data recording, storage, and sharing can effectively reduce governance costs and improve governance efficiency.

Application layer: The application layer can design public chain and alliance chain networks based on the degree of decentralization and governance entities for ordinary government systems and non-governmental systems, and private chains for government confidential systems, and users can access them based on the network The entrance provides diversified services and truly realizes the co-construction and sharing of data.

Target layer: The target layer is the target task of our management.
In addition, it also includes the application layer, incentive layer, consensus layer, network layer, and data layer. They are nothing more than simplifications in the appeal architecture, and will not be introduced in detail here.