区块链场景,区块链怎么进入
近几年，随着区块链技术的发展，区块链场景也在不断拓展。本文将介绍区块链场景拓展的三个关键词：去中心化，数字资产，智能合约。
去中心化是区块链技术最核心的概念之一，也是区块链技术在传统金融领域取得成功的关键原因。去中心化的核心思想是，通过区块链技术，将数据存储在网络的多个节点上，而不是集中存储在单一的服务器上，从而使得数据更加安全可靠。同时，去中心化还可以消除信任和管理问题，实现自治管理，让参与者之间可以相互信任，共同完成交易。
数字资产是指通过区块链技术发行的虚拟货币，其中包括比特币、以太坊等。数字资产的发行是通过区块链技术实现的，因此它们具有去中心化、安全可靠等特点。此外，数字资产还可以通过智能合约实现去中心化的交易，从而极大的提高了交易的安全性和便捷性。
智能合约是区块链技术中一种特殊的编程语言，可以用来实现去中心化的交易。智能合约可以实现自动执行，在双方都满足指定条件的情况下，可以自动完成交易，从而大大提高交易的安全性和便捷性。此外，智能合约还可以用来实现去中心化的数据共享，从而使参与者之间可以相互信任，共同完成交易。
以上就是区块链场景拓展的三个关键词：去中心化、数字资产和智能合约，它们的出现使得区块链技术的应用范围更加广泛，为传统金融领域带来了极大的改变。
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① What is blockchain
What is blockchain
What is blockchain? Many people have no idea what blockchain is. It is not very clear, and some people have even never heard of it. In fact, blockchain is a common technology. I have compiled relevant information about what blockchain is for everyone.
What is blockchain 1Speaking 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, you might as well 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. There is no wayDid some sneaky stuff.
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 miss a few entries intentionally or unintentionally, 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 do not have to worry about their works being stolen but getting nothing...
What is blockchain 2From an academic perspective, blockchain is New application models 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 stores all the above information.Save it and then encrypt 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 the blockchain is decentralized, it can facilitate peer-to-peer transactions, so whether you are trading or exchanging funds, there is no need for a third party of approval.
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 center that provides a cloud computing platform.ation institutions. 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 find and place orders for hotels and other services, and each platform gets commissions from them.
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 3Advantages of blockchain
Decentralized, it does not require a thirdThe intervention of three parties 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 way of virtual currency, its advantages will play an important role in many industry fields
② What is needed to learn blockchain technology Conditions
From the current talent demand in the blockchain field, it can be roughly divided into the following categories:
1. Build a distributed ledger application based on DLT technology and implement customer requirements on DLT business needs. Ripple is currently more famous in this field. So what DLT means, you will understand if you look at what Ripple is doing.
2. Develop your own applications on existing public chains. Most companies are currently doing this. This category is also characterized by low barriers to entry, high business potential, and low risks.
3. The company develops its own public chain. This type has the greatest future potential, but the risk and technical difficulty are also the highest.
4. Blockchain ecological infrastructure. For example, mobile wallets, hardware cold wallets, trading platforms, blockchain content platforms, etc. This category is currently the blockchain industry with the highest commercial profits. It has relatively low barriers and low risks, but there are many competitors.
If you start with technology, what languages and knowledge do you need to learn?
For the first category, go language is necessary, because DLT is basically based on go language, and it also needs to master certain application development capabilities, because what is delivered to customers must be one piece of software rather than a bunch of Command line source program. As for the second category, the current mainstream of smart contracts is still the solidity language of Ethereum smart contracts, so if you want to enter the second category of companies, you need to start with Ethereum. For the third type of public chain development, the mainstream ones are C++ and Go, but there are also many famous projects implemented in Rust, such as: Facebook's Libra, Huobi Public Chain's Nervos, etc. The fourth category actually has little to do with blockchain technology, soBlockchain technology is not required for developments such as trading platforms.
In addition to the above technical hard power, the talents that blockchain companies prefer are "slash youths", that is, talents who master knowledge in multiple fields at the same time. They are mainly divided into three categories: finance and regional Blockchain, content operation and blockchain, community operation and blockchain. Among them, the third type of talents is the rarest, because most technical talents are not good at communication. However, due to its distributed characteristics, blockchain particularly requires the joint efforts of the community to create and Maintain a chain.
Finally, many people mistakenly believe that blockchain is a brand new industry and that blockchain is completely incompatible with traditional fields. This is actually a big misunderstanding. From what is written above, you can also find that blockchain In the final analysis, blockchain still has to solve actual needs in reality. The only difference is that the tools for solving needs have changed. So don’t think that just knowing blockchain can kill everyone. Choose the demand field you want to enter, and have the necessary skills in that demand field. The basic knowledge required is still very important.
The application fields of blockchain include digital currency, certificates, finance, anti-counterfeiting and traceability, privacy protection, supply chain, entertainment, etc. With the popularity of blockchain and Bitcoin, many related top domain names have been registered. , which has had a relatively large impact on the domain name industry.
③ Why does a transaction in the blockchain require 6 blocks of confirmation? Is it a rigid rule?
This is not a rigid rule and has nothing to do with the blockchain. . There is a relationship between the algorithm of this coin and the confirmation method of each coin is different, so this is not a hard and fast rule.
The number of confirmations for Bitcoin, Ritecoin, Litecoin, and Dogecoin are all different.
④ What is the six-layer model of the blockchain?
The blockchain has a total of six levels of structure. These six levels of structure from bottom to top are: data layer, network layer , consensus layer, incentive layer, contract layer, and application layer.
1. Data Layer
The data layer is the bottom 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. Below we introduce the upper layers of the data layer.One 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 Proof of Stake
(POS), EOS's Delegated Proof of Stake (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.
It’s likeBitcoin's consensus mechanism, PoW, stipulates that the more work you do, the more you get. Whoever can find the correct hash value first will get a certain number of Bitcoin rewards;
Ethereum's PoS stipulates that who The longer the currency is held, the greater the probability of who can get the reward.
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.
⑤ What are the six major stages of blockchain use case development
Blockchain is a point-to-point digital distributed ledger that records all transactions and information that occur in the peer-to-peer network. It cannot be tampered with, only appended. The following are the six major stages of blockchain use case development analyzed by Jinwowo Network Technology:
Analyze services and processes → Define technical blueprint → Develop concepts → Policy and regulatory framework → Develop pilot → Scale
One of the three conditions for realizing large-scale implementation of blockchain application is blockchain 3.0 technology, which can improve the performance of blockchain , improve ease of use, operability, and scalability, involving new side chains, sub-chains, cross-chains, layering, sharding, partitioning and other technologies. According to Xiao Feng’s observation, most of these technologies will mature in 2019, and the mainnet will be online. The launch of these new technologies is the prerequisite for large-scale commercial application of blockchain. Therefore, from a technical perspective, we can expect large-scale commercial applications of blockchain after 2019.
The second is that the maturity of the technology is not enough. To truly realize a large number of Dapps and a large number of commercial applications on the blockchain, one must also be prepared: that is, the realDigital currency that can be used as a payment instrument, medium of exchange, value scale, and value storage. Xiao Feng said that everyone thinks that Bitcoin is a payment system, but the real Bitcoin cannot meet our payment needs because its currency value fluctuates too much.
As an example, he said that a shopping mall sold a bottle of water and accepted Bitcoin payment. When he got up the next morning, he found that 20% of the value was gone. So it cannot be accepted. After the Japanese Diet clarified that Bitcoin can be used as a payment instrument, some Japanese merchants announced that they accept Bitcoin payments. But it later turned out that it caused a lot of trouble for the stability of the company's balance sheet. Up or down, your balance sheet is unstable. This not only affects whether the things sold are valuable, but also affects the company's credit evaluation and the services provided by the bank to the company.
The third condition is the construction of laws and regulations and the construction of a regulatory system. The digital economy on the blockchain must be legally protected and must be compliant. Xiao Feng emphasized that in this regard, there is no possibility of decentralization.
The difference between blockchain and the Internet gives my own point of view. He believes that the core difference between the two is that the Internet is a centralized trust mechanism, while the blockchain is a decentralized trust mechanism that does not require trust in a third party.
The second core difference between the Internet and blockchain is the incentive mechanism, not digital currency or whether coins can be issued. Economics has long discussed the problem of incentive incompatibility. Under the corporate system, on the Internet, the incompatibility of incentive mechanisms has not been resolved. But on the decentralized blockchain, the blockchain achieves complete incentive compatibility. There are no shareholders, no board of directors, and no employees, and conflicts of interest between these roles will no longer occur.
⑦ 108 knowledge points for getting started with blockchain
1. What is blockchain
Combine the information of multiple transactions and the information indicating the block The information is packaged and put together, and the verified package is the block.
Each block stores the hash value of the previous block, creating a relationship between blocks, that is to say, a chain. Together they are called blockchain.
2. What is Bitcoin
The concept of Bitcoin was proposed by Satoshi Nakamoto in 2009, with a total number of 21 million. The Bitcoin chain generates a block approximately every 10 minutes, and this block is mined by miners for 10 minutes. As a reward to miners, a certain number of Bitcoins will be issued to miners, but this certain number is halved every four years. Now it's 12.5. If this continues, all Bitcoins will be available in 2040.
3. What is Ethereum
The biggest difference between Ethereum and Bitcoin is the smart contract. This allows developers to develop and run various applications on it.
4. Distributed ledger
It is a kind of distributed ledger between network members.Shared, replicated and synchronized databases. To put it bluntly, all users on the blockchain have accounting functions and the content is consistent, which ensures that the data cannot be tampered with.
5. What is quasi-anonymity?
I believe everyone has a wallet, and the wallet address (a string of characters) used to send transactions is quasi-anonymity.
6. What is open transparency/traceability
The blockchain stores all data from history to the present, anyone can view it, and can also view any data in history.
7. What is tamper-proof
Historical data and current transaction data cannot be tampered with. The data is stored in the block on the chain and has a hash value. If the block information is modified, its hash value will also change, and the hash values of all blocks following it must also be modified to form a new chain. At the same time, the main chain is still conducting transactions to generate blocks. The modified chain must always generate blocks synchronously with the main chain to ensure that the length of the chain is the same. The cost is too high, just to modify a piece of data.
8. What is anti-DDoS attack
DDoS: Hackers control many people’s computers or mobile phones and allow them to access a website at the same time. Since the bandwidth of the server is limited, a large amount of traffic The influx of data may cause the website to fail to function properly, resulting in losses. However, the blockchain is distributed and there is no central server. If one node fails, other nodes will not be affected. Theoretically, if more than 51% of the nodes are attacked, problems will occur.
9. Definition of main chain
Taking Bitcoin as an example, at a certain point in time, a block is mined by two miners at the same time, and then 6 blocks are generated first. The chain of blocks is the main chain
10. Single chain/multi-chain
Single chain refers to the data structure that handles everything on one chain. The core essence of the multi-chain structure is composed of public chain + N sub-chains. There is only one, but in theory there can be countless sub-chains, and each sub-chain can run one or more DAPP systems
11. Public chain/alliance chain/private chain
Public Chain: Everyone can participate in the blockchain
Alliance chain: Only alliance members are allowed to participate in accounting and query
Private chain: Writing and viewing permissions are only controlled by one person In the hands of the organization.
12. Consensus layer, data layer, etc.
There are six overall structures of the blockchain: data layer, network layer, consensus layer, incentive layer, contract layer, and application layer. Data layer: a layer that records data, belonging to the underlying technology; network layer: an architecture for building a blockchain network, which determines the userHow to organize it with users. Consensus layer: Provides a set of rules to allow everyone to reach agreement on the information received and stored. Incentive layer: Design incentive policies to encourage users to participate in the blockchain ecosystem; Contract layer: Generally referred to as "smart contracts", it is a set of contract systems that can be automatically executed and written according to their own needs. Application layer: Applications on the blockchain, similar to mobile apps. Former Distributed Storage R&D Center
13. Timestamp
The timestamp refers to the time from January 1, 1970 Day 0 hours 0 minutes 0 seconds 0... The total number of seconds from the current time to now, or the total number of nanoseconds and other very large numbers. Each block is generated with a timestamp indicating when the block was generated.
14. Block/block header/block body
Block is the basic unit of blockchain, and block header and block body are components of blockchain. The information contained in the block header includes the hash of the previous block, the hash of this block, timestamp, etc. The block body is the detailed data in the block.
15. Merkle tree
Merkle tree, also called binary tree, is a data structure for storing data. The bottom layer is the original data contained in all blocks, and the upper layer is each The hash value of a block, the hash of this layer is combined in pairs to generate a new hash value, forming a new layer, and then upwards layer by layer, until a hash value is generated. Such a structure can be used to quickly compare large amounts of data, and you can quickly find the bottom-level historical data you want without downloading all the data.
16. What is expansion?
The size of a Bitcoin block is about 1M and can save 4,000 transaction records. Expansion means making the block larger so that more data can be stored.
17. What is a chain?
Each block will save the hash of the previous block, creating a relationship between the blocks. This relationship is a chain. Data such as block transaction records and status changes are stored through this chain.
18. Block height
This is not the height mentioned in terms of distance. It refers to the total number of blocks between the block and the first block on the chain. This height indicates which block it is, and is just for identification purposes.
19. Fork
Two blocks were generated at the same time (the transaction information in the block is the same, but the hash value of the block is different), and then in Two chains are forked from these two blocks. Whoever generates 6 blocks from these two links first will be the main chain, and the other chain will be discarded.
20. Ghost Protocol
A mine with high computing powerPools can easily produce blocks faster than miners with lower computing power, resulting in most of the blocks on the blockchain being generated by these mining pools with high computing power. However, the blocks generated by mining machines with low computing power are not stored on the chain because they are slow, and these blocks will be invalid.
The ghost protocol allows blocks that should be invalidated to remain on the chain for a short time, and can also be used as part of the proof of work
. In this way, miners with small computing power will contribute more to the main chain, and large mining pools will not be able to monopolize the confirmation of new blocks.
21. Orphan blocks
As mentioned before, orphan blocks are blocks generated at the same time. One of them forms a chain, and the other does not form a chain. Then this block that does not form a chain is called an orphan block.
22. Uncle block
The orphan block mentioned above, through the ghost protocol, makes it part of the proof of work, then it will not be discarded and will be saved in the main chain superior. This block is the next
23 replay attack
The hacker resends the message that has been sent to the server. Sometimes this can deceive the server into multiple responses.
24. Directed acyclic graph
Also called data set DAG (directed acyclic graph), DAG is an ideal multi-chain data structure. Most of the blockchains mentioned now are single chains, that is, one block is connected to another block, and DAG is multiple blocks connected. The advantage is that several blocks can be generated at the same time, so the network can process a large number of transactions at the same time, and the throughput will definitely increase. However, there are many shortcomings and it is currently in the research stage.
25. What is mining
The mining process is to perform a series of conversions, connections and hash operations on the above six fields, and continue to try them one by one. The random number you are looking for, and finally successfully find a random number that meets the conditions: the value after hashing is smaller than the hash value of the preset difficulty value, then the mining is successful, and the node can broadcast the area to neighboring nodes. block, neighboring nodes receive the block and perform the same operation on the above six fields to verify compliance, and then forward it to other nodes. Other nodes also use the same algorithm to verify. If there are 51% of nodes in the entire network If all verifications are successful, even if this block is truly "mined" successfully, each node will add this block to the end of the previous block, delete the list in the block that is the same as its own record, and resurrect again. the above process. Another thing to mention is that regardless of whether the mining is successful or not, each node will pre-record the reward of 50 Bitcoins and the handling fees of all transactions (total input-total output) in the first item of the transaction list (this is " The most fundamental purpose of "mining" is also the fundamental reason to ensure the long-term stable operation of the blockchain), the output locationThe address is the address of this node, but if the mining fails, the transaction will be invalidated and there will be no reward. Moreover, this transaction called "production transaction" does not participate in the "mining" calculation.
26. Mining machines/mining farms
Mining machines are computers with various configurations, and computing power is the biggest difference between them. A place where mining machines are concentrated in one place is a mining farm
27. Mining pool
Miners join together to form a team, and the computer group under this team is a mining pool. Mining rewards are distributed based on your own computing power contribution.
28. Mining difficulty and computing power
Mining difficulty is to ensure that the interval between generating blocks is stable within a certain short time, such as Bitcoin’s 10 minutes.
p>Block 1. The computing power is the configuration of the mining machine.
29. Verification
When verification in the blockchain is a confirmation of the legality of the transaction, each node will verify the transaction once when the transaction message is propagated between nodes. Whether the transaction is legal. For example, verify whether the syntax of the transaction is correct, whether the transaction amount is greater than 0, whether the entered transaction amount is reasonable, etc. After passing the verification, it will be packaged and handed over to the miners for mining.
30. Transaction broadcast
The node sends information to other nodes through the network.
31. Mining fees
For the blockchain to work non-stop like a perpetual motion machine, miners need to maintain the system. Therefore, the miners must be given favorable fees to make it sustainable.
32. Transaction confirmation
When a transaction occurs, the block recording the transaction will be confirmed for the first time, and will be confirmed in every area on the chain after the block. Block is reconfirmed: When the number of confirmations reaches 6 or more, the transaction is generally considered safe and difficult to tamper with.
33. Double transaction
That is, I have 10 yuan, I use the 10 yuan to buy a pack of cigarettes, and then instantly use the 10 yuan that has not yet been paid. Bought another cup of coffee. So when verifying the transaction, you need to confirm whether the 10 yuan has been spent.
34. UTXO unspent transaction output
It is a data structure containing transaction data and execution code, which can be understood as digital currency that exists but has not yet been consumed.
35. Transactions per second TPS
That is throughput, tps refers to the number of transactions the system can process per second.
36. Wallet
Similar to Alipay, it is used to store digital currencies, and blockchain technology is more secure.
37. Cold wallet/hot wallet
A cold wallet is an offline wallet. The principle is to store it locally and use QR code communication to prevent the private key from touching the Internet. A hot wallet is an online wallet. The principle is to encrypt the private key and store it on the server. When it is needed, it is downloaded from the server and decrypted on the browser side.
38. Software Wallet/Hardware Wallet
A software wallet is a computer program. Generally speaking, a software wallet is a program that interacts with the blockchain and allows users to receive, store, and send digital currencies and can store multiple keys. Hardware wallets are smart devices that specialize in handling digital currencies.
39. Airdrop
The project sends digital currency to each user’s wallet address.
40. Mapping
Mapping is related to the issuance of blockchain currency and is a mapping between chains. For example, there are some blockchain companies that have not completed the development of the chain in the early stage. They rely on Ethereum to issue their own currency. The issuance and transactions of the early currency are all operated on Ethereum. With the development of the company, the company's own chain development has been completed. The company wants to map all the previous information on Ethereum to its own chain. This process is mapping.
41. Position
Refers to the ratio of the investor’s actual investment to the actual investment funds
42. Full position
Buy with all funds Enter Bitcoin
43. Reduce the position
Sell some of the Bitcoins, but not all of them
44. Heavy positions
Compared with Bitcoin, Bitcoin accounts for a larger share of funds
45. Short position
Compared with Bitcoin, the share of funds is larger
46. Short position
Sell all the Bitcoins you hold and convert them all into funds
47. Stop loss
After obtaining a certain profit, sell the Bitcoin held to keep the profit
48. Stop loss
After losses reach a certain level, sell the Bitcoins you hold to prevent further losses
49. Bull market
Prices continue to rise and the outlook is optimistic
50. Bear market
The price continues to fall, and the outlook is bleak
51. Long (long)
The buyer believes that the currency price will rise in the future, buys the currency, and waits for the currency price After rising, sell at a high price to take profits
52. Short position (short selling)
The seller believes that the currency price will fall in the future, and sells the currency he holds (or borrows currency from the trading platform) until the currency price drops. Then, buy at a low price and take profits
53. Open a position
Buy virtual currencies such as Bitcoin
54. Cover a position
Buy virtual currencies such as Bitcoin in batches, for example: buy 1 BTC first, then buy 1 BTC
55. Full position
Buy all funds into a certain currency at once A kind of virtual currency
56. Rebound
When the currency price falls, the price rebounds and adjusts because it falls too fast
57. Consolidation (sideways)
The price fluctuation is small and the currency price is stable
58. Falling
The currency price is slowly declining
59. Diving (waterfall)
The currency price fell rapidly and to a large extent
60. Cutting meat
After buying Bitcoin, the currency price fell. To avoid expanding the loss, sell Bitcoin at a loss. . Or after borrowing the currency to go short, the currency price rises, and you buy Bitcoin at a loss
61. Hold on
Expect the currency price to rise, but unexpectedly the currency price falls after buying; or expect the currency price fell, but unexpectedly, after selling, the currency price rose
62. Unwinding
After buying Bitcoin, the currency price fell, causing a temporary book loss, but then the currency price rebounded and the loss was reversed To make a profit
63. Going short
After selling Bitcoin because of the bearish market outlook, the price of the currency continued to rise, and I was unable to buy it in time, so I failed to make a profit
64. Overbought
The currency price continues to rise to a certain height, the buyer's power is basically exhausted, and the currency price is about to fall
65. Oversold
The currency price continues to fall to a certain low, the seller's power has basically been exhausted, and the currency price is about to rise
66. Lure bulls
The currency price has been consolidating for a long time, and it is more likely to fall. Most of the short sellers have sold Bitcoin, and suddenly the short sellers pulled up the price of the currency, inducing the long parties to think that the price of the currency will rise and buy one after another. As a result, the short sellers suppressed the price of the currency, causing the long parties to get stuck
67. Lure shorts
After buying Bitcoin, bulls deliberately suppress the price of the currency, making short sellers think that the price of the currency will fall and sell them one after another. As a result, they fall into the trap of bulls
68. What is NFT
The full name of NFT is "Non-Fungible Tokens", which is non-fungible tokens. Simply put, it is an indivisible copyright certificate on the blockchain. , its main function is to confirm and transfer the rights of digital assets. The difference from digital currency is that it is unique and indivisible. In essence, it is a unique digital asset.
69. What is the Metaverse
The Metaverse is a collection of virtual time and space, consisting of a series of augmented reality (AR), virtual reality (VR) and the Internet (Internet) Composed of digital currency, which carries the function of value transfer in this world.
70. What is DeFi
DeFi, the full name is Decentralized Finance, which is "decentralized finance" or "distributed finance". "Decentralized finance", as opposed to traditional centralized finance, refers to various financial applications based on open decentralized networks. The goal is to establish a multi-level financial system based on blockchain technology and cryptocurrency. As a basis, re-create and improve the existing financial system
71. Who is Satoshi Nakamoto?
72. Bitcoin is different from Q Coin
Bitcoin is a decentralized digital asset with no issuing entity. Q Coin is an electronic currency issued by Tencent. It is similar to electronic points, but it is not actually a currency. Q Coin requires a centralized issuing institution. Q Coin can only be recognized and used because of the credit endorsement of Tencent. The scope of use is also limited to Tencent's games and services. The value of Q coins is entirely based on people's trust in Tencent.
Bitcoin is not issued through a centralized institution, but it is widely recognized around the world because Bitcoin can self-certify its trust. The issuance and circulation of Bitcoin are jointly accounted for by miners across the entire network, and are not A central authority is also needed to ensure that no one can tamper with the ledger.
73. What is a mining machine?
Taking Bitcoin as an example, a Bitcoin mining machine is a professional equipment that competes for accounting rights by running a large amount of calculations to obtain new Bitcoin rewards. It is generally composed of a mining chip, a heat sink and a fan, and only performs A single calculation program consumes a lot of power. Mining is actually a competition between miners for computing power. Miners with more computing power have a greater probability of mining Bitcoin. As the computing power of the entire network increases, it becomes increasingly difficult to mine bits with traditional equipment (CPU, GPU), and people have developed chips specifically for mining. The chip is the core part of the mining machine. The operation of the chip will generate a large amount of heat. In order to dissipate heat, Bitcoin mining machines are generally equipped with heat sinks and fans. Users download Bitcoin mining software on their computers and use the software to allocate the tasks of each mining machine.Start mining. Each currency has a different algorithm and requires different mining machines.
74. What is quantitative trading?
Quantitative trading, sometimes also called automated trading, refers to the use of advanced mathematical models to replace human subjective judgments, which greatly reduces the impact of investor sentiment fluctuations and avoids extreme fanaticism or pessimism in the market. make irrational investment decisions. There are many types of quantitative trading, including cross-platform trading, trend trading, hedging, etc. Cross-platform trading means that when the price difference between different target platforms reaches a certain amount, sell on the platform with a higher price and buy on the platform with a lower price.
75. Blockchain asset over-the-counter trading
Over-the-counter trading is also called OTC trading. Users need to find their own counterparties and do not need to match the transaction. The transaction price is determined by negotiation between the two parties. The two parties can fully communicate through face-to-face negotiation or telephone communication.
76. What is a timestamp?
The blockchain ensures that each block is connected sequentially through timestamps. Timestamps enable every piece of data on the blockchain to have a time stamp. Simply put, timestamps prove when something happened on the blockchain and cannot be tampered with by anyone.
77. What is a blockchain fork?
Upgrading software in a centralized system is very simple, just click "Upgrade" in the app store. However, in decentralized systems such as blockchain, "upgrading" is not that simple, and a disagreement may even cause a blockchain fork. Simply put, a fork refers to a disagreement when the blockchain is "upgraded", resulting in a fork in the blockchain. Because there is no centralized organization, every code upgrade of digital assets such as Bitcoin needs to be unanimously recognized by the Bitcoin community. If the Bitcoin community cannot reach an agreement, the blockchain is likely to form a fork.
78. Soft fork and hard fork
Hard fork means that when the Bitcoin code changes, the old nodes refuse to accept the blocks created by the new nodes. Blocks that do not comply with the original rules will be ignored, and miners will follow the original rules and create new blocks after the last block they verified. A soft fork means that old nodes are not aware of the changes to the Bitcoin code and continue to accept blocks created by new nodes. Miners may work on blocks they have no understanding of, or validation of. Both soft forks and hard forks are "backwards compatible" to ensure that new nodes can verify the blockchain from scratch. Backward compatibility means that new software accepts data or code generated by old software. For example, Windows 10 can run Windows XP applications. Soft forks can also be "forward compatible".
79. Classification and application of blockchain projects
Judging from the current mainstream blockchain projects, there are mainly four blockchain projects:Category: The first category: currency; the second category: platform category; the third category: application category; the fourth category: asset tokenization.
80. USDT against the US dollar
USDT is Tether USD, a token launched by Tether that is against the US dollar (USD). 1USDT=1 US dollar, users can use USDT and USD for 1:1 exchange at any time. Tether implements a 1:1 reserve guarantee system, that is, each USDT token will have a reserve guarantee of 1 US dollar, which supports the stability of the USDT price. The unit price of a certain digital asset is USDT, which is equivalent to its unit price in US dollars (USD).
81. Altcoins and alternative coins
Altcoins refer to blockchain assets that use the Bitcoin code as a template and make some modifications to its underlying technology blockchain, among which Those with technological innovations or improvements are also called alternative coins. Because the Bitcoin code is open source, the cost of plagiarism in Bitcoin is very low. You can even generate a brand new blockchain by simply copying the Bitcoin code and modifying some parameters.
82. Three major exchanges
Binance: https://accounts.binancezh.ac/zh-CN
Okex: https://www .ouyi.top/
Huobi: https://www.huobi.af/zh-cn
83. Market software
Mytoken: http: //www.mytoken.com/
Non-small account: https://www.feixiaohao.co/
84. Information website
Babbitt: https://www.8btc.cn
Golden Finance: http://www.jinse.com/
Coin World News: http://www.bishijie.com < /p>
85. Blockchain Explorer
BTC: https://btc.com/
ETH: https://etherscan.io/
BCH: https://blockchair.com/bitcoin-cash/blocks
LTC: http://www.qukuai.com/search/ltc
ETC：https://gastracker.io/
86. Wallet
Imtoken: https://imatoken.net/
Bitpie: https:// bitpie.com/
87. Decentralized exchange
uniswap: https://uniswap.org
Opensea: https://opensea.io
Super Rare: https://superrare.com/
89. Ladder
Bring your own, buy a reliable ladder
90. Platform currency
Digital currency issued by the platform, used to deduct handling fees, transactions, etc.
p>91. Bull market, bear market
Bull market: rising market
Bear market: falling market
92. Blockchain 1.0
< p> A currency trading system based on distributed ledgers, represented by Bitcoin93. Blockchain 2.0
The contract blockchain technology represented by Ethereum (smart contract) is 2.0
94. Blockchain 3.0
In the era of intelligent Internet of Things, it goes beyond the financial field to provide decentralized solutions for various industries
95. Intelligence Contract
Smart Contract is a computer protocol designed to disseminate, verify or execute contracts in an information-based manner. Simply put, an electronic contract is set in advance and once confirmed by both parties, the contract is automatically executed.
96. What is a token?
The token economy is an economic system with Token as the only reference standard, which is equivalent to a pass. If you own Token, you have rights and interests, and you have the right to speak.
Big data is the means of production, AI is the new productivity, and blockchain is the new production relationship. Big data refers to a collection of data that cannot be captured, managed and processed within a certain time range using conventional software tools. It is a massive, high-growth and high-volume data set that requires new processing models to have stronger decision-making power, insight discovery and process optimization capabilities. Diverse information assets. Simple theoryThe explanation is that big data is massive data accumulated over a long period of time and cannot be obtained in the short term. Blockchain can be used as a way to obtain big data, but it cannot replace big data. Big data is only used as a medium running in the blockchain and has no absolute technical performance, so the two cannot be confused. (A simple understanding of production relations is labor exchange and consumption relations. The core lies in productivity, and the core of productivity lies in production tools)
ICO, Initial Coin Offering, initial public token issuance, is the first step in the blockchain digital currency industry. Crowdfunding. It is the most popular topic and investment trend in 2017, and the country launched a regulatory plan on September 4. Speaking of ICO, people will think of IPO, and the two are fundamentally different.
99. Five characteristics of digital currency
The first characteristic: decentralization
The second characteristic: having open source code
The third feature: independent electronic wallet
The fourth feature: constant issuance
The fifth feature: global circulation
100. What is decentralization?
It has no issuer, does not belong to any institution or country, and is a publicly issued currency designed, developed and stored on the Internet by Internet network experts.
100. What is measurement (scarcity)?
Once the total amount of issuance is set, it is permanently fixed, cannot be changed, cannot be over-issued at will, and is subject to global Internet supervision. Because the difficulty of mining and mining changes over time, the longer the time, the greater the difficulty of mining, and the fewer coins are mined, so it is scarce.
101. What is open source code?
The alphanumeric code is stored on the Internet. Anyone can find out the source code of its design, everyone can participate, can mine it, and it is open to the world.
102. What is anonymous transaction? Private wallet private?
Everyone can register and download the wallet online without real-name authentication. It is completely composed of encrypted digital codes. It can be sent and traded globally in real-time point-to-point without resorting to banks or any institutions. It cannot be traced by anyone without my authorization. ,Inquire.
A contract transaction refers to an agreement between a buyer and seller to receive a certain amount of an asset at a specified price at a certain time in the future. The objects of contract trading are standardized contracts formulated by the exchange. The exchange stipulates standardized information such as commodity type, transaction time, quantity, etc. A contract represents the rights and obligations of the buyer and seller.
105. Digital goodsCoin industry chain
Chip manufacturers, mining machine manufacturers, mining machine agents, mining and mining, and retail investors on exchanges for currency speculation
106. Two books who is it?
Erben: Digital Currency Value Investor
Investment style: Steady
Building a community: Erben’s Miscellaneous Talks (High Quality Price Investment Community)
p>
107. Two investment strategies
Combining long and short term, focusing on price investment, no touching contracts, no short-term play
Reasonable layout, scientific operation, prudent and conservative, making periodic money
108. Two books?
Welcome currency friends and seek common development
⑧ What are the application scenarios of blockchain?
Although the current blockchain technology is still in its early stages, However, the advantages of this technology have begun to be reflected. In many fields, blockchain can generate huge value. I believe there will be more practical application scenarios in the future.
Blockchain + Cross-border Payment
The current mainstream cross-border remittance method is wire transfer, and its cycle is generally three to five working days, except for the intermediate bank that will charge a certain handling fee. In addition, a company called SWIFT (Society for Worldwide Interbank Financial Telecommunication) will also charge higher fees for the message exchange carried out by its system. In my country, cross-border remittances through Bank of China will be charged a single fee of 150 yuan. .
The use of blockchain technology allows the remitter and payee to pay and settle directly, eliminating all intermediate costs, allowing cross-border payment and settlement to be completed quickly point-to-point, improving In addition to the speed of clearing, it can also achieve round-the-clock payment, real-time arrival, simple implementation and no hidden costs.
