区块链连接起来的是,区块链连接起来的是hash

区块链是近几年发展迅速的一项技术，它将一系列的数据块连接在一起，以形成一个安全可信的分布式数据库，可以用来存储和管理数据。而它的核心技术就是hash拓展。

Hash拓展是一种数字摘要技术，它可以将任意长度的数据转换成固定长度的散列值，用来标识数据的完整性和安全性。它是区块链技术的基础，在区块链系统中，每个区块都有一个唯一的hash值，这个hash值是根据区块中的数据信息计算出来的，如果区块中的数据发生改变，hash值也会发生改变，从而保证了数据的完整性和安全性。

Merkle树是一种特殊的hash拓展树，它可以将一组数据压缩成一个唯一的hash值，以表示数据的完整性，并可以用来验证数据的完整性。Merkle树是区块链技术的核心组成部分，它可以将一大堆数据压缩成一个唯一的hash值，以表示数据的完整性，并可以用来验证数据的完整性。Merkle树的另一个优势是，它可以提高区块链的存储效率，因为它可以将一大堆数据压缩成一个唯一的hash值，从而减少了存储空间的使用。

智能合约是一种特殊的电子合同，它可以自动执行指定的条款，以实现自动化的交易。智能合约是基于区块链技术的，它可以利用hash拓展和Merkle树等技术来保证交易的安全性和可信性，从而实现自动化的交易。智能合约的优势在于，它可以实现自动化的交易，减少了人工操作的错误，并且可以提高交易的效率和安全性。

总之，hash拓展、Merkle树和智能合约是区块链技术的核心技术，它们可以实现数据安全、可信、自动化的交易，从而提高了区块链的存储效率和交易效率，为社会发展和经济发展做出了重要的贡献。
请查看相关英文文档

① The components of the blockchain

The components of the blockchain are as follows:

Openness: Block The system data of the chain is open and transparent, and everyone can participate. For example, when renting a house, you can know the previous rental information of the house and whether there have been any problems. Of course, some personal private information here is encrypted.

Autonomy: The blockchain adopts consensus-based specifications and protocols (such as a set of open and transparent algorithms), and then each node operates according to this specification, so that everything is completed by machines , there is no human element. This changes trust in people to trust in machines, and any human intervention has no effect.

The information cannot be tampered with: If the information is stored in the blockchain, it will be saved permanently and there is no way to change it. As for the 51% attack, it is basically impossible to achieve.

Anonymity: There is no personal information on the blockchain, because it is all encrypted and is a string of letters and numbers, so your various ID card information and phone number will not appear. Numbers are being resold.

② How are the blocks in the blockchain connected?

Experts said that the blockchain can be commonly understood as a distributed public ledger, which is composed of various Blocks are connected into a chain. In traditional accounting systems, accounting rights are in the hands of the central server.

On the "ledger" of the blockchain, every point in the chain can record information on it, forming a point-to-point accounting system. Therefore, blockchain technology is considered a decentralized technology.

For example, in a village of 100 people, Zhang San bought a cow from Li Si and paid him 10,000 yuan. In the past, he had to rely on the middleman Zhao Liu to transfer his 10,000 yuan to Li Si.

With the blockchain system, Zhang San can directly record his 10,000 yuan into Li Si’s account book, and at the same time, the transaction information will be transmitted to the whole village, that is, the entire blockchain system. Make the information visible to 98 other people. The system records the entire transaction process, which has the advantage of traceability and prevents problems such as the loss of Zhao Liu's account book or Li Si's refusal to acknowledge the account.

(2) The blockchain is connected by version. Extended reading

The concept of blockchain was first proposed by Satoshi Nakamoto in 2008. , and in the years that followed, blockchain became a core component of the electronic currency Bitcoin: serving as the public ledger of all transactions. By leveraging peer-to-peer networks and distributed timestamp servers, blockchain databases can be managed autonomously.

The blockchain invented for Bitcoin made it the first digital currency to solve the problem of repeated consumption. Bitcoin's design has become a source of inspiration for other applications.

③ What does blockchain mean?

Blockchain is an important concept of Bitcoin. It is essentially a decentralized database that simultaneously operatesWu Zhibu is the underlying technology of Bitcoin. It is a series of data blocks generated using cryptographic methods. Each data block contains a batch of Bitcoin network transaction information, which is used to verify the validity of its information. (anti-counterfeiting) and generate the next block.

Blockchain is a new application model of computer technology such as distributed data storage, point-to-point transmission, consensus mechanism, and encryption algorithm.

2. In order to realize the great leap forward development of blockchain finance, in order to promote the new development of China's economy, accelerate the circulation of global assets, and realize the renaissance that generations have been striving for. dream.

Puyin Group held a Puyin Blockchain Finance Guiyang Strategy Release Ceremony in Guizhou on December 9, 2016. At the meeting, the blockchain will realize the digital circulation of assets and the blockchain financial transaction model. , and discuss the application of blockchain services and social public industries.

④ Let you quickly understand the technical model architecture of blockchain in 1 minute

Blockchain technology is not a single technology, but a combination of multiple technologies that are innovative. As a result, it is essentially a weakly centered, self-reliant underlying architecture technology.
The blockchain technical model includes the data information layer, the consensus layer of the transmission layer, the incentive layer, the contract layer and the network layer from top to bottom. Each layer has an important role, and different levels cooperate with each other to build a value transfer system that goes to the management center.

The characteristics of the data information layer are that it cannot be forged, fully backed up data, and completely fair (data information, management permissions, coding), and its algorithm design is a blockchain, including blockchain headers and blocks material. The blockchain header consists of three sets of blockchain databases. One set of databases is the parent blockchain hash value, which is used to connect the block to the previous block in the blockchain. The second set of databases is the Merkle root. An algorithm designed to effectively summarize all transactions in the blockchain; the three sets of databases are the difficulty target, time format and Nonce related to the production of the blockchain.

The transport layer encapsulates technologies such as P2P network mechanism, dissemination and authentication mechanism. In the transport layer, new transactions are broadcast to major websites. Each node will include the received transaction information in a blockchain, and each node will try to add it to its own blockchain. Find a proof of workload with sufficient difficulty. When a node finds a proof of workload (qualified to package the blockchain), it broadcasts the program (newly packaged blockchain) to major websites. When And only if all transactions included in the block are valid and have not existed before, other nodes will recognize the validity of the block, and the way to express acceptance is to follow the block. At the end of the block, a new block is created to add to the chain, and any hash of the accepted block is treated as any hash of the new block.

The consensus layer encapsulates various consensus algorithms of nodes, which is an important technology of the blockchain, because it determines the formation of the blockchain, and the accounting decision-making method may affect the stability of the entire system. safety factor and stability. At present, more than ten consensus mechanism algorithms have been produced, among which the well-known ones are the proof-of-work mechanism (POW), the easy-to-use Byzantine fault tolerance algorithm (PBFT), the proof-of-interest mechanism (POS), and the equity authorization proof mechanism.

The encouragement layer includes an offering system and an incentive system. Simply put, the incentive system is to encourage nodes to participate in maintaining the optimal operation of the blockchain system in a balanced economic manner, to avoid falsification of the general ledger, and to maintain the driving force for the operation of the blockchain network in the long term.

The contract layer has the characteristics of a programmable controller, which mainly includes smart contracts, consensus algorithms, scripting, and coding. It is the basis for the characteristics of a blockchain programmable controller. Insert the code into the blockchain or dynamic password to implement a customizable smart contract, and under certain specific constraints, it can be executed automatically without going through a third party, which is trustworthy in the blockchain. Basic.
The network layer encapsulates various application fields and examples of blockchain, which is very similar to computer applications and portals on computer browsers. It deploys blockchain core technologies on things such as Ethereum. , EOS and implemented in practice.

#BTC[超话]# #digital currency#

⑤ What is blockchain

What is blockchain

< p> What is blockchain? Many people are not very clear about what blockchain is. Some people have even never heard of it. In fact, blockchain is a common technology. I will explain it to everyone. We have compiled relevant information on what blockchain is.

What is blockchain 1

Speaking of blockchain, we have to mention its twin brother-Bitcoin.

Time goes back to 11 years ago. On November 1, 2008, the world was shrouded in the huge shadow of the financial crisis. That day, a mysterious geek who called himself "Satoshi Nakamoto" sent a group email.

Attached to the email is a paper titled: "Bitcoin: A Peer-to-Peer Electronic Cash System."

Satoshi Nakamoto said in the email that he is working on a new electronic cash system that is completely peer-to-peer and does not require any trusted third party. About half a month later, Satoshi Nakamoto released the source code of the Bitcoin system non-stop.

On January 3, 2009, an interesting invention turned out. Satoshi Nakamoto generated the first Bitcoin block on the server, which is the so-called "Bitcoin genesis block". Since then, the Bitcoin system has officially opened.

Having said that,Let’s stop and think about how we conduct cash transactions in real life.

Suppose you borrow 10,000 yuan from a friend and promise to pay it back in one month. You may choose to repay the loan by bank card transfer. The bank is responsible for deducting 10,000 yuan from your deposit account and adding 10,000 yuan to your friend's deposit account.

Here, the bank is the institution responsible for keeping accounts. The underlying reason why you choose bank transfer is that you believe it is more reliable and will help you transfer 10,000 yuan to a friend.

However, in the digital world, inventing a currency is another matter.

The hero behind the Bitcoin game

First of all, Satoshi Nakamoto hopes to conduct peer-to-peer direct transactions, bypassing the third party of the bank. This problem is easy to solve. Then there will be no banks. Users will issue their own currencies through a unique mechanism and trade directly with each other.

But this brings another problem. There is no bank as a reliable intermediary responsible for accounting, and users do not know each other. How to ensure that no one cheats during transactions?

For example, in the digital world, electronic files can be easily copied. 10 yuan of digital currency turns into 100 yuan by copying and pasting it with the mouse 10 times. Isn’t it a mess?

To solve this problem, we need to provide a mechanism for everyone to trust each other.

The method adopted by the Bitcoin system is to record all transaction processes openly and transparently in chronological order. These records are permanent and cannot be tampered with. This way you won't be able to do anything sneaky.

With these mechanisms, the Bitcoin system operates successfully.

This system stores data in units of data blocks, which are blocks. Approximately every 10 minutes, new blocks will be added. Each block records the detailed transaction process of Bitcoin and is timestamped. Different blocks are connected in chronological order through a certain algorithm, which is a chain.

Together, they are called "Blockchain".

In this way, the blockchain took root with the birth of Bitcoin. If Bitcoin is the star in front of the spotlight, blockchain is the hero behind the scenes responsible for providing a trust mechanism in the underlying technology.

Brand new changes in accounting methods

Although behind the scenes, the talent of blockchain was quickly discovered.

In technical terms, blockchain is a distributed ledger technology. To understand it, let’s take the simplest example.

Suppose your family keeps accounts like this: you, your father, and your mother each have an account book. You each record your own expenses, and at the end of each month, you tally the total household expenses together.

But dad likes to buy cigarettes, mom likes to stock up on cosmetics, and you like to buy snacks. You may both be interested in each other intentionally or unintentionally.I accidentally write down a few entries, and sometimes make corrections in the ledger. Therefore, when checking the accounts at the end of the month, there is always a discrepancy with the actual expenditure of the family.

In order to change this situation, you bought a new account book. You, your father, and your mother jointly use a new account book to keep accounts, remind and supervise each other, and check each expense together.

At the same time, you also agreed that once the expenses are clearly recorded, no alteration or deletion is allowed. After trying it for a few months, you found that this joint ledger matched the actual expenses of the family much more closely.

Blockchain is the second accounting method. The little story above tells us that it has at least these major features or benefits.

First of all, it is decentralized. The database that was previously maintained by one party has become jointly maintained by multiple parties. Everyone writes data together based on consensus, and no one can control the data alone.

Secondly, it allows everyone to change from keeping separate accounts to joint accounting, which brings consistency and openness and transparency to the data.

In addition, the blockchain only allows data to be written, not deletion or modification, which prevents data from being secretly tampered with.

Mutual trust between strangers

In reality, many scenarios are much more complicated than how to keep accounts at home. Moreover, many aspects of financial transactions and business processing are mostly operated by strangers. How can we make everyone trust each other?

It’s blockchain’s turn to show its talents. Don’t forget, it can provide a mechanism for everyone to trust each other from the underlying technology.

For example, when you usually go to the wet market to buy things, you may worry about whether fish, shrimp, and vegetables are safe. Some companies see business opportunities and move the data of farmers and fish ponds to the blockchain. In this way, you will know which fish pond the fish you buy comes from, and you will feel more confident when eating.

For another example, links to fundraising for seriously ill patients often appear in Moments. When making a donation, you may have some concerns: Is the patient's condition real? Can donations really be delivered to patients?

In order to eliminate these concerns, some Internet charity organizations use blockchain to allow you to clearly view the steps for using your donation. If the review finds that the patient's condition is not true, the blockchain system will automatically return the donation to your account.

In the future, what changes can blockchain bring to our lives?

It is conceivable that when blockchain is widely used in various fields of society, it will become an important infrastructure in the information age and can solve many of the headaches that currently cause us.

For example, blockchain will allow countless islands of information to be "chained" together. When seeing a doctor, there is no need to repeat the examination just because you change hospitals. Entrepreneurs do not have to go to multiple departments to go through a procedure; many transactions no longer need to be carried out. Third-party guarantees are required, consumers no longer have to worry about non-refundable deposits, and creators don’t have to worry about their works being stolen but getting nothing...

What is blockchain 2

From an academic perspective, blockchain is a new application model of computer technologies such as distributed data storage, point-to-point transmission, consensus mechanisms, and encryption algorithms. Blockchain is essentially a decentralized database.

Many people still don’t understand this explanation, so let me make a simple metaphor.

Hypothetical situation: Suppose you have a ledger at home and you are asked to keep accounts. In the past, your parents gave you your salary and asked you to record it in your account book. If you are greedy and want to buy something delicious in the meantime, the record in the ledger may be less than ten yuan.

This is just an example. I believe that when we were children, everyone probably wanted to take some money from their parents’ pockets to spend.

Ways to use blockchain to solve problems:

If you use the whole family mobilization method to keep accounts, the above-mentioned problems will not exist, because you are keeping accounts, and your father They are also keeping accounts, and your mother is also keeping accounts. They can all see the general ledger. You can't change it, and neither can your parents. So your father who wants to buy cigarettes and you who want to eat have nothing to do.

Functional "blockchain"

It can not only record every transaction, but also can be programmed to record almost everything of value to mankind. Things: birth and death certificates, marriage licenses, title deeds, degrees, financial accounts, medical history, insurance claims, ballots, food sources, and anything else that can be represented by a code.

Each block is like a hard disk, which saves all the above information and then encrypts it through cryptography technology. The saved information cannot be tampered with.

Every 10 minutes, the blockchain system will check all data generated during the period (such as transaction records and records of when the block was edited or created, etc.) and store these data in a new area. On the block, this block will be connected with the previous block to form a chain. Each block must contain relevant information from the previous block to be effective.

Characteristics of blockchain

1. Exceptionally safe:

Unlike centralized databases owned by companies or government agencies, blockchain is not controlled by anyone. or entity's control, data is replicated (distributed) in its entirety across multiple computers.

Unlike centralized databases, there is no single entry point for attackers, and data security is more guaranteed.

2. Non-tamperability:

Once entered into the blockchain, no information can be changed, and even the administrator cannot modify this information.

Once something appears, it cannot be changed. This attribute is of great significance to the changeable and ever-changing online world that humans currently live in.

3. Accessible:

All nodes in the network can easily access information.

4. No third party:

Because blockchain is decentralized, it facilitates peer-to-peer transactions, so whether you are trading or exchanging funds, no third-party approval is required.

Blockchain itself is a platform.

Blockchain technology refers to a way for all people to participate in accounting. There is a database behind all systems. You can think of the database as a big ledger. Currently, each is keeping its own account.

Since there is no centralized intermediary agency, letting everything run automatically through preset programs can not only greatly reduce costs, but also improve efficiency. And since everyone has the same ledger, it can ensure that the ledger recording process is open and transparent.

Blockchain technology is the underlying technology of Bitcoin. Without the operation and management of any centralized organization, Bitcoin has been operating very stably for many years without any problems, so some people have noticed its The underlying technology abstracts the Bitcoin technology and calls it blockchain technology, or distributed ledger technology.

According to a report released by Santander, Spain's largest bank, if all banks around the world use blockchain technology internally around 2020, they will save approximately US$20 billion in costs per year. Such data is enough to illustrate the tremendous changes and breakthroughs that "blockchain" has brought to the traditional financial field.

Cloud computing is usually defined as providing dynamic, easily scalable and often virtualized resources through the Internet, but it is often a centralized organization that provides a cloud computing platform. The network composed of blockchain generally does not have a specific organization, so blockchain is closer to the definition of a distributed computing system and is a type of distributed computing.

The future development and application scenarios of blockchain

1. Digital identity

Many people will encounter "prove that my mother is me" when applying for various certificates. "Mom" dilemma, with blockchain, you no longer have to worry about it.

It turns out that our birth certificates, real estate certificates, marriage certificates, etc. need a central node for everyone to recognize them. Once cross-border, contracts and certificates may become invalid because of the lack of a global central node.

The non-tamperable nature of blockchain technology has fundamentally changed this situation. Our birth certificates, real estate certificates, and marriage certificates can all be notarized on the blockchain and become things trusted by the world. , of course, it can also easily prove "my mother is my mother".

2. Health care

Simply put, it is to use the blockchain to establish a universal record repository with timestamps, so that different databases can extract data information.

For example, when you go to see a doctor, you don’t have to change hospitals for repeated examinations, and you don’t have to worry about reimbursement for medical insurance, which can save time and expenses.

3. Travel consumption

For example, we often use apps such as Ctrip and Meituan to findAnd place orders for hotel stays and other services, from which each platform gets a commission.

The application of blockchain is to remove middlemen and create a secure, decentralized way for service providers and customers to connect and trade directly.

4. More convenient transactions

Blockchain can make payments and transactions more efficient and convenient. The blockchain platform allows users to create smart contracts that become active when certain conditions are met, meaning that automatic payments can be released when both parties to a transaction agree that their conditions are met.

5. Strictly control product quality

If you buy an apple, with blockchain technology, you can know the entire process from the production of the fruit farmer to the circulation link. Among them are government regulatory information, professional testing data, enterprise quality inspection data, etc. A smart supply chain will make the food we eat and the products we use every day safer and give us more peace of mind.

6. Property rights protection art

The creator puts his work on the blockchain, and if someone uses his work, he can immediately Know. Corresponding royalties are also automatically paid to the creator.

Blockchain technology not only protects copyright, but also helps creators sell their works to consumers better and more directly, without the need for the assistance of distribution companies.

What is blockchain 3

Advantages of blockchain

Decentralized, it does not require the intervention of a third party and enables point-to-point transactions, coordination and collaboration. Because the data is distributed in various nodes through algorithms and has a unique verification mechanism, no one organization or individual can control the global data. Since it is distributed in various nodes, any node stopping work will not affect the entire system. Operation, this decentralized network will greatly improve data security. The data in the system is jointly maintained by various nodes with maintenance functions.

Openness, in addition to the encryption of private information of all parties in the system, the blockchain data is open to everyone, and anyone can query the blockchain through the public interface Data and development related applications, so the entire system information is highly transparent.

Where does blockchain come in?

Blockchain is an open, transparent, decentralized and secure technology. This technological revolution is applied to the Internet. For data-sensitive fields such as medical care, public opinion supervision, and ecological testing, it can prevent data from being tampered with and ensure the authenticity of the data.

In short, blockchain is not just a method of virtual currency, its advantages will play an important role in many industry fields

⑥ Blockchain Technology

Background: After the birth of Bitcoin, it was discovered that the technology was very advanced, and blockchain technology was discovered. Bitcoin and blockchain technology were discovered at the same time.

1.1 The purpose of the birth of Bitcoin:

① Currency transactions are recorded, that is, ledgers;

② Disadvantages of centralized institution accounting - can be tampered with; Yi Chaofa< /p>

Bitcoin solves the first problem: anti-tampering - hash function

1.2 hash function (encryption method)

① Function: convert a string of any length , converted into fixed-length (sha256) output. The output is also called a hash value.

② Features: It is difficult to find two different x and y such that h(x)=h(y).

③Application: md5 file encryption

1.3 Blockchain

①Definition

Block: Split the general ledger into zones Block storage

Blockchain: On each block, add a block header. It records the hash value of the parent block. By storing the hash value of the parent block in each block, all blocks are connected in order to form a blockchain.

②How does the blockchain prevent transaction records from being tampered with?

After the blockchain is formed, tampering with any transaction will cause the hash value of the transaction block to be different from that of its sub-blocks. , tampering was discovered.

Even if you continue to tamper with the hash value in the sub-block header, the hash value in the sub-block will be different from that in the grandchild block, and the tampering will be discovered.

1.4 The essence of blockchain

①The essence of Bitcoin and blockchain: a big ledger visible to everyone, only recording transactions .

②Core technology: Through cryptographic hash function + data structure, it ensures that the ledger records cannot be tampered with.

③Core function: Create trust. Fiat currency relies on government credibility, and Bitcoin relies on technology.

1.5 How to trade

① To conduct transactions, you need an account number and password, corresponding to the public key and private key

Private key: a string of 256-bit binary numbers , you don’t need to apply for it, you don’t even need a computer, you can generate the private key by tossing a coin 256 times

The address is converted from the private key. The address cannot reverse the private key.

The address is the identity, which represents the ID in the Bitcoin world.

After an address is generated, it can only be known by everyone if it enters the blockchain ledger.

②Digital signature technology

Signature function sign (Zhang San’s private key, transfer information: Zhang San transfers 10 yuan to Li Si) = signature of this transfer

< p> Verify Korean verify (Zhang San’s address, transfer information: Zhang San transfers 10 yuan to Li Si, signature of this transfer) = True

Zhang San uses his own private key through the signature function sign() key to sign this transaction.

Anyone can verify whether the signature was issued by Zhang San himself who holds Zhang San's private key by verifying the Korean vertify(). It returns true, otherwise it returns false.

sign() and verify() are cryptographically guaranteed not to be cracked. ·

③Complete the transaction

Zhang San will provide the transfer information and signature to the entire network. Under the premise that the account has a balance, after verifying that the signature is true, it will be recorded in the blockchain ledger. Once recorded, Zhang San's account will be reduced by 10 yuan, and Li Si's account will be increased by 10 yuan.

Supports one-to-one, one-to-many, many-to-one, and many-to-many transactions.

In the Bitcoin world, private keys are everything! ! !

1.6 Centralized Accounting

① Advantages of Centralized Accounting:

a. No matter which center keeps accounts, don’t worry too much

< p> b. Centralized accounting, high efficiency

②Disadvantages of centralized accounting:

a Denial of service attack

b Stop service after getting tired

p>

c Central institutions are vulnerable to attacks. For example, destroying servers and networks, committing self-intrusion, legal termination, government intervention, etc.

All attempts at confidential currencies with centralized institutions in history have failed.

Bitcoin solves the second problem: how to decentralize

1.7 Decentralized accounting

①Decentralization: Everyone can keep accounts. Everyone can keep a complete ledger.

Anyone can download open source programs, participate in the P2P network, monitor transactions sent around the world, become an accounting node, and participate in accounting.

② Decentralized accounting process

After someone initiates a transaction, it is broadcast to the entire network.

Each accounting node continues to monitor and continue transactions across the entire network. When a new transaction is received and the accuracy is verified, it is put into the transaction pool and continues to be propagated to other nodes.

Due to network propagation, the transactions of different accounting nodes at the same time are not necessarily the same.

Every 10 minutes, from all accounting nodes, extractPick 1, use its transaction pool as the next block, and broadcast it to the entire network.

Other nodes delete the transactions that have been recorded in their own transaction pool based on the transactions in the latest block, continue accounting, and wait for the next selection.

③ Features of decentralized accounting

A block is generated every 10 minutes, but not all transactions within these 10 minutes can be recorded.

The accounting node that obtains the accounting rights will be rewarded with 50 Bitcoins. After every 210,000 blocks (approximately 4 years), the reward is halved. The total amount is about 21 million, and it is expected to be mined in 2040.

Recording the reward of a block is also the only way to issue Bitcoin.

④ How to allocate accounting rights: POW (proof of work) method

Compete for accounting rights by calculating mathematical problems on several accounting points.

Find a random number that makes the following inequality true:

There is no other solution except traversing the random numbers starting from 0 and trying your luck. The process of solving the problem is also called mining.

Whoever solves the problem correctly first will get the accounting rights.

If a certain accounting node finds the solution first, it will announce it to the entire network. After other nodes verify that it is correct, a new round of calculation will start again after the new block. This method is called POW.

⑤ Difficulty adjustment

The generation time of each block is not exactly 10 minutes

As Bitcoin develops, the computing power of the entire network does not increase.

In order to cope with changes in computing power, the difficulty will be increased or decreased every 2016 blocks (about 2 weeks), so that the average time for each block to be generated is 10 minutes.

#欧易OKEx# #BTC[超话]# #digital currency#

⑦ What is the popular explanation of blockchain? You must know the five major application scenarios of blockchain. !

Recently, blockchain has become popular overnight, and everyone around is discussing blockchain.

So, is the blockchain the same as Bitcoin?

In fact, Bitcoin and blockchain are not the same thing.

Blockchain is the underlying technology of Bitcoin, but the first usage scenario after the birth of blockchain is Bitcoin.

Bitcoin is just a string of data in a computer. Compared with paper currency, it is also called a "virtual currency". To put it simply, you can understand that Bitcoin is just a string of numbers with cash value, similar to Q coins. In other words, Bitcoin has no actual value. Its current value is supported by the beliefs of currency speculators. IfWithout faith, the value of Bitcoin will collapse.

What is blockchain? What are the characteristics of blockchain technology?

Let’s first take a look, why is blockchain called blockchain?

Data is stored piece by piece, and the data stored piece by piece is called a block. Different blocks are linked to the previous block, which is called a blockchain.

For example:

On a certain day of a certain year, Lao Wang lent Xiao Wang 10,000 yuan, and Lao Wang told everyone around him the news , the transfer records were posted on WeChat Moments, and everyone helped them testify to the existence of this transaction.

Lao Wang and Xiao Wang are two nodes. These two nodes generate transaction time, location, person and other information, and they are packaged to form a "block". Lao Wang’s friends are also nodes. These nodes jointly record the transaction status and details (blocks) of the two nodes Lao Wang and Xiao Wang. These blocks are connected to form a blockchain.

Fundamentally, blockchain is a distributed ledger database.

What does distributed ledger mean?

Let’s take a look at the traditional accounting method.

The traditional accounting method is a centralized accounting method. For example, if Lao Wang lent 10,000 yuan to Xiao Wang, if Lao Wang did not tell the world about this money, then this amount would Only Lao Wang knows about the money transactions, Xiao Wang knows, God knows, and Earth knows. This accounting method is a centralized accounting method. This method has a very fatal shortcoming: what should I do if the other party does not acknowledge the account? In fact, in real life, in spontaneous private lending relationships, there is no evidence when the lending relationship occurs, resulting in many cases where the other party does not acknowledge the debt afterwards.

The accounting method adopted by Lao Wang from the beginning has prevented future troubles. This method is the blockchain distributed ledger, which has the characteristics of decentralization and allows everyone to It is the center and everyone can testify to the existence of this deal.

In addition to the characteristics of decentralization, blockchain also has the characteristics of being immutable. In the blockchain, if the data in any one block changes, even if it only changes a punctuation mark, it will become invalid and needs to be recalculated. Therefore, in the blockchain technology, once a piece of data changes, the cost will be Very big. Unless all nodes in this blockchain have 51% control. Therefore, the blockchain system will be stable and secure.

It’s still Lao Wang and Xiao Wang. If Xiao Wang wants to default on his debt, he can’t tamper with it unless he bribes everyone in the world who knows about the transaction.

Blockchain is also open and transparent.

In blockchain technology, all dataIs it public, or is it an example of Lao Wang and Xiao Wang.

If Xiao Wang does not acknowledge the money, once this news is released, then Xiao Wang’s reputation will be ruined. He can only release new news and wash away the money by paying back the money. Clear your own identity.

Some people say that if the blockchain is so powerful, will my identity information be revealed and there will be no privacy? In fact, the blockchain has the characteristics of anonymity and protects our privacy very well. Unless required by legal regulations, technically speaking, the identity of each block node does not need to be disclosed or verified and can be done anonymously.

What are the applications of blockchain?

The origin of blockchain is to solve the problem of trust, and one of the most successful applications of blockchain is digital currency. Bitcoin is arguably the most successful application of blockchain so far.

In addition to digital currency, the future applications of Bitcoin are still very wide, and blockchain technology has been widely used in different industries. Such as product traceability, copyright protection and transactions, payment and settlement, Internet of Things, digital marketing, medical care, etc., promoting different industries to quickly enter the "blockchain+" era.

1. Payment and clearing

The role of the intermediary bank can be abandoned, point-to-point payment can be realized, intermediary fees can be reduced, and fund utilization can be accelerated.

2. Product traceability

For example, if we buy a piece of clothing on a certain website, we can see the past and present life of this piece of clothing.

3. Securities trading

Traditional securities trading requires the coordination of four major institutions, which is inefficient and costly. Blockchain technology can independently complete one-stop services.

4. Supply chain

Introduce blockchain technology into the supply chain system, synchronize information within the system, control all links, and better complete division of labor and collaboration. , to facilitate accountability afterwards.

5. Intellectual property rights

With copyright on the chain, our photographic works, musical works, literary works, etc. will become our information, and the ownership of the information will be confirmed and become our property.

⑧ Easy-to-understand explanation of blockchain

The popular explanation of blockchain technology is as follows:

To put it simply: blockchain is the use of a package of existing A new generation of network system formed using advanced network technology. This network system has a new structure, a new mechanism, and unprecedented new value. Five major technologies or innovations are specifically used: encryption technology, P2P network technology, distributed storage technology, consensus mechanism, and smart contracts.

Essentially: it is a shared database, and the data or information stored in it is "unforgeable" and "completely traceable"Features such as “traceability”, “openness and transparency” and “collective maintenance”. Based on these characteristics, blockchain technology has laid a solid foundation for "trust and sales" and created a reliable "cooperation" mechanism. Yunchun has broad application prospects.

2. Openness.

In addition to encrypting the private information of all parties to the transaction, the blockchain data is open to everyone and provides a flexible script code system. The entire system information is highly transparent and within the rules specified by the system. Nodes cannot deceive each other.

3. Autonomy.

Consensus technology, smart contracts.