区块链远端节点通信原理,区块链 节点 如何通信

A. I just learned about it. Can anyone tell me what blockchain is and explain it in a simple way?

The way everyone keeps accounts together is also known as "Distributed" or "decentralized" because everyone keeps accounts, and the accuracy of the ledger is determined by a program algorithm rather than an authoritative organization.

This is the blockchain. The core is finished. The blockchain is as simple as a common ledger

The six core algorithms of blockchain technology:

Blockchain Core Algorithm 1: Byzantine Agreement

The story of Byzantium goes like this: The Byzantine Empire has huge wealth, and its 10 neighboring countries have been around for a long time, but Byzantium’s high walls stand tall. It was so impregnable that no single neighbor could 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.

Blockchain Core Algorithm 2: Asymmetric Encryption Technology

In the above-mentioned Byzantine Agreement, if several of the 10 generals initiate messages at the same time, it will inevitably cause chaos in the system. As a result, each has its own attack time plan, making it difficult to coordinate actions. Anyone can launch an offensive message, but who will send it? In fact, this only requires adding a cost, that is: only one node can spread 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.

Blockchain Core Algorithm Three: Fault Tolerance Issues

We assume that in this network, messages may be lost, damaged, delayed, and sent repeatedly, and the order in which they are received is different from the order in which they are sent. Inconsistent. 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 Four: Paxos Algorithm (Consistency 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 inIn many scenarios, it 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 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 device. Decentralized storage in every corner of the network. Therefore, distributed storage technology does not store complete data on each computer, but splits the data and stores it in different computers. It's like storing 100 eggs, not in the same basket, but in different places. The total sum is 100. If you want to know more, you can use the Internet search, Internet search results - little knowledge

B. What is the blockchain

Blockchain is a kind of data "hash verification" "Functional database. Blocks are data blocks. Data blocks are combined into a chain structure in chronological order, and cryptographic algorithms are used to collectively maintain the reliability of the database in a distributed accounting manner. All data blocks are connected in chronological order, forming a blockchain.
The 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 blocks and related basic data and basic algorithms such as data encryption and timestamps; the network layer includes distributed networking mechanisms, data dissemination mechanisms, and data verification mechanisms; the consensus layer mainly encapsulates network nodes Various consensus algorithms; 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 various scripts, algorithms and smart contracts, and is the core of the blockchain The basis of programmable features; the application layer encapsulates various application scenarios and cases of the blockchain. In this model, the chain block structure based on timestamps, the consensus mechanism of distributed nodes, economic incentives based on consensus computing power, and flexible programmable smart contracts are the most representative innovations of blockchain technology.
Blockchain mainly solves the trust and security issues of transactions, so it proposes four technological innovations to address this issue:
(1) Distributed ledger, which means that transaction accounting is performed by multiple accounts distributed in different places. The nodes work together, and each node records a complete account, so they can all participate in supervising the legality of the transaction., and can also jointly testify for it.
Different from traditional distributed storage, the uniqueness of blockchain distributed storage is mainly reflected in two aspects: First, each node of the blockchain stores complete data according to the block chain structure. Distributed storage generally divides data into multiple parts for storage according to certain rules. Second, the storage of each node in the blockchain is independent and has equal status, relying on the consensus mechanism to ensure the consistency of storage, while traditional distributed storage generally synchronizes data to other backup nodes through the central node. [8]
No node can record ledger data independently, thus avoiding the possibility of a single bookkeeper being controlled or bribed to record false accounts. Also because there are enough accounting nodes, theoretically speaking, the accounts will not be lost unless all nodes are destroyed, thereby ensuring the security of the accounting data.
(2) Asymmetric encryption and authorization technology. The transaction information stored on the blockchain is public, but the account identity information is highly encrypted and can only be accessed with authorization from the data owner, thus ensuring data security and personal privacy.
(3) Consensus mechanism is how all accounting nodes reach a consensus to determine the validity of a record. This is both a means of identification and a means of preventing tampering. Blockchain proposes four different consensus mechanisms, which are suitable for different application scenarios and strike a balance between efficiency and security.
The consensus mechanism of the blockchain has the characteristics of "the minority obeys the majority" and "everyone is equal". "The minority obeys the majority" does not entirely refer to the number of nodes, but can also be computing power, the number of shares, or other computers. Feature quantities that can be compared. "Everyone is equal" means that when a node meets the conditions, all nodes have the right to give priority to the consensus result, which will be directly recognized by other nodes and may eventually become the final consensus result. Taking Bitcoin as an example, it uses proof of work. Only when more than 51% of the accounting nodes in the entire network are controlled, it is possible to forge a non-existent record. When there are enough nodes joining the blockchain, this is basically impossible, thus eliminating the possibility of fraud.
(4) Smart contracts, smart contracts are based on these trustworthy and non-tamperable data and can be automated Enforce some predefined rules and terms. Take insurance as an example. If everyone's information (including medical information and risk occurrence information) is true and trustworthy, it will be easy to carry out automated claims settlement in some standardized insurance products
In fact Individuals can simply understand that it is actually a financial database.

C. The nodes in the blockchain network include

The nodes in the blockchain network include mobile phones, mining machines, servers, etc.
Nodes refer to computers in the blockchain network. Blockchains are participated by a large number of individuals or family users. Each individual or family is a node of the blockchain.
The blockchain is composed of small blocks. Everyone who forms a block node does not know each other, but they trust each other becauseThey also have a common purpose, that is, they all want to obtain the rewards of the mechanism.

D. Introduction to Blockchain Technology What is Blockchain Technology

1. Blockchain technology is one of the top ten typical judicial technology applications on the Internet.

2. Blockchain is a term in the field of information technology. In essence, it is a shared database, and the data or information stored in it has the characteristics of "unforgeable", "full traces left", "traceable", "open and transparent" and "collectively maintained". Based on these characteristics, blockchain technology has laid a solid foundation of "trust" and created a reliable "cooperation" mechanism, which has broad application prospects.

3. Generally speaking, the blockchain system consists of data layer, network layer, consensus layer, incentive layer, contract layer and application layer.

4. Among them, the data layer encapsulates the underlying data blocks and related data encryption and timestamps and other basic data and basic algorithms; the network layer includes distributed networking mechanisms, data dissemination mechanisms and data The verification mechanism is obvious; the consensus layer 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; the contract layer mainly encapsulates various Class scripts, algorithms and smart contracts are the basis of the programmable features of the blockchain; the application layer encapsulates various application scenarios and cases of the blockchain. In this model, the chain block structure based on timestamps, the consensus mechanism of distributed nodes, economic incentives based on consensus computing power, and flexible programmable smart contracts are the most representative innovations of blockchain technology.

5. The consensus mechanism of the blockchain has the characteristics of "the minority obeys the majority" and "everyone is equal". Among them, "the minority obeys the majority" does not entirely refer to the number of nodes, but also to computing power. , number of shares, or other characteristic quantity that a computer can compare. "Everyone is equal" means that when a node meets the conditions, all nodes have the right to give priority to the consensus result, which will be directly recognized by other nodes and may eventually become the final consensus result. Taking Bitcoin as an example, Caizihe uses proof of work. Only if he controls more than 51% of the accounting nodes in the entire network, is it possible to forge a non-existent record. When there are enough nodes joining the blockchain, this is basically impossible, thus eliminating the possibility of fraud.

E. What is a node in the blockchain?

A node is a server in a region. In the Internet area, all the running data of an enterprise is in one server, then this server is the node.
Just like WeChat, which we use every day, it handles so many chat messages, transfers, etc. every day. This data is stored and run on Tencent's servers. Then we can call this server that processes data a "node".
Let’s talk about the world of blockchain. Everyone already knows that blockchain is a decentralized distributed database.It does not rely on any centralized server, but is composed of thousands of "small servers". As long as we download a blockchain client, we become one of the thousands of "little servers".

In this way, if we want to play with the blockchain, we ourselves are equivalent to a node.
Nodes are also divided into light nodes and full nodes. A full node is a node that owns all the transaction data of the entire network, while a light node is a node that only owns transaction data related to itself.
And the more and more widely the nodes are distributed, the more decentralized the blockchain network will be, and the safer and more stable the network operation will be. The existence of nodes is a symbol of blockchain distribution and is also the charm of blockchain