区块链项目的开发的顺序是什么,区块链项目的开发的顺序是怎样的

近年来，区块链技术的发展迅速，许多企业和组织都在尝试将其应用到各种项目中。但是，如果要开发一个完整的区块链项目，那么必须了解开发的顺序。那么，区块链项目的开发顺序是什么？

首先，在开发区块链项目之前，必须先完成需求分析。需求分析是一个非常重要的步骤，它涉及到项目的范围、目标、功能、时间节点等内容，可以帮助开发者更好地理解项目的要求，从而制定出更好的计划。

其次，开发者可以进行技术选型，选择适合项目的技术框架，帮助开发者更好地实现项目的目标。在技术选型过程中，开发者还需要考虑到项目的安全性、可扩展性、可维护性等问题，以确保项目的高质量。

第三，开发者可以进行架构设计，构建项目的架构，定义各个模块之间的关系和交互方式，并确定每个模块的功能和职责。

第四，开发者可以开始编写代码，根据设计的架构，编写出各个模块的实现代码，并确保代码的质量，以确保项目的可靠性。

最后，开发者还需要进行测试，确保项目的功能和性能都能够满足预期，并且可以正常运行。如果发现了任何问题，开发者还需要进行修复，以确保项目的高质量。

总的来说，区块链项目的开发顺序是：需求分析→技术选型→架构设计→编码→测试。只有按照这样的顺序来开发区块链项目，才能确保项目的高质量和可靠性。

请查看相关英文文档

1. The development of blockchain applications has gone through several stages

Principles of blockchain technology

By definition, blockchain is a A traceable chain data structure that combines continuously generated information blocks in a chronological order and is a distributed ledger that cryptographically ensures that the data cannot be tampered with or forged.

Blockchain is an innovative application formed by combining asymmetric encryption algorithms, consensus mechanisms, distributed storage, point-to-point transmission and other related technologies in new ways. The biggest advantage and direction of blockchain technology is "decentralization". By using cryptography, consensus mechanisms, game theory and other technologies and methods, decentralized credit-based decentralization can be realized in a distributed system where network nodes do not need to trust each other. Peer-to-peer trading.

The excellent characteristics of blockchain come from its unique technical foundation. A basic blockchain must at least consist of three parts: data layer, network layer and consensus layer.

The data layer provides a unique data structure to ensure security, and uses asymmetric encryption, hash function, Merkle tree and other technologies to encrypt data to ensure data security and provide the basis for blockchain applications;

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The network layer realizes the core idea of ​​decentralization through the P2P network. In the BitTorrent network, each node is both a data receiver and a data sender.

In blockchain technology, the public key is similar to a seed. With the public key, you have an identity that can speak in the network. At present, the consensus mechanisms mainly include PoW, PoS and DPoS consensus mechanisms. If you want to attack the blockchain, you must provide greater computing power than Zhu Lian. The benefits obtained are far less than the cost of the attack. The PoW consensus mechanism competes through computing power. Ensure the security and decentralization of the system.

——For more data and analysis, please refer to the "Forward-looking Industry Research Institute" China Blockchain Industry Market Prospects and Investment Strategic Planning Analysis Report".

2. ​ 108 knowledge points for getting started with blockchain

108 essential knowledge points for getting started with blockchain

(Welcome to communicate with fellow fans)

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1. What is a blockchain

The information of multiple transactions and the information indicating the block are packaged together. 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, there must beA certain number of Bitcoins will be issued to miners, but this certain amount 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 database that is shared, replicated and synchronized among network members. 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 in the hands of one 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: a structure for building a blockchain network, which determines how users are organized. 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 oneSame, just the hash value of the block is different), and then two chains are forked from these two blocks. Whoever generates 6 blocks first from these two links will be the main chain, and the other chain throw away.

20. Ghost Protocol

Mining pools with high computing power can easily generate blocks faster than mining machines with low 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 next

23 replay attack

The hacker resends the message that has been sent to the server. Sometimes this can defraud the server of 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 mining is successful or not, each node will pre-compute the rewards.50 Bitcoins, and the handling fees of all transactions (total input - total output) are recorded in the first item of the transaction list (this is the most fundamental purpose of "mining" and the fundamental reason to ensure the long-term stable operation of the blockchain ), the output address is the address of this node, but if mining fails, the transaction will be invalidated without any reward. Moreover, this transaction called "production transaction" does not participate in the "mining" calculation.

26. Mining machines/mines

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 is issued in 10 minutes

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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

and paymentSimilar to Bao, it is used to store digital currency, and it is more secure using blockchain technology.

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

Prices continue 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)

Seller,If you think the currency price will fall in the future, sell the currency you hold (or borrow currency from the trading platform). After the currency price drops, buy it at a low price to take profits

53. Open a position

Buy Bitcoin and other virtual currencies

54. Cover position

Buy Bitcoin and other virtual currencies in batches, for example: buy 1 BTC first, then buy 1 BTC

55. Full position

Buy all the funds into a certain virtual currency at one time

56. Rebound

Currency price When falling, 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. Yin fall

The currency price falls slowly

59. Diving (waterfall)

The currency price falls rapidly and to a large extent

60. Cutting meat

After buying Bitcoin, the price of the currency fell. In order to avoid expanding the loss, the Bitcoin was sold at a loss. Or after borrowing the currency to go short, the currency price rises, and then buying Bitcoin at a loss

61. Holding up

Expecting the currency price to rise, but unexpectedly the currency price falls after buying; or expecting the currency price to rise. 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. Go 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 is basically 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 and locked up the long parties.

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 a non-fungible token. Simply put, it is an indivisible token on the blockchain. Copyright certificate, mainly used to confirm and transfer digital assets, the difference from digital currency is that it is unique and indivisible, and is essentially 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?

Satoshi Nakamoto is the developer and founder of Bitcoin. Satoshi Nakamoto published the Bitcoin white paper on November 1, 2008, and mined Bitcoin for the first time on January 3, 2009. Whoever can use the Bitcoin in the genesis block is Satoshi Nakamoto himself, so who Is it Satoshi Nakamoto? There have been many "Satoshi Nakamotos" in history: In 2013, someone revealed that Mochizuki Shinichi, who had made outstanding contributions in the field of mathematics, was Satoshi Nakamoto, but no direct evidence was provided. In 2014, hackers broke into the mailbox used by Satoshi Nakamoto and found the owner of the mail, Dorian Nakamoto. Later, Dorian said that he only obtained the mailbox address and password by chance, not Nakamoto. Cong. In 2016, Craig Wright said that he was Satoshi Nakamoto and could provide Satoshi Nakamoto's private key. But later, Wright withdrew his statement because he could not face everyone's doubts.

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 device that competes for accounting rights by running a large amount of calculations to obtain rewards for new Bitcoins.It is generally composed of a mining chip, a heat sink and a fan. It only executes a single calculation program and 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, use the software to assign tasks to each mining machine, and then 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. The miners may have no idea what they are doingsolution, or work on verified blocks. 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, blockchain projects mainly fall into four categories: Category 1: 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

Okex

Huobi

83. Market software

Mytoken

Non-small account

84. Information website

Babbitt

Golden Finance

Coin World News

85. Blockchain Browser

BTC

ETH

BCH

< p> LTC

ETC

86. Wallet

Imtoken

Bitpie

MetaMask (Little Fox)

87. Decentralized exchange

uniswap

88. NFT exchange

< p> Opensea

Super Rare

89. Ladder

Bring your own, buy a reliable ladder

90. Platform currency

A digital currency issued by the platform. Used to deduct handling fees, transactions, etc.

91. Bull market, bear market

Bull market: rising market

Bear market: falling market

92. Blockchain 1.0

A currency trading system based on distributed ledgers, represented by Bitcoin

93. Blockchain 2.0

Ethereum (intelligent The contract blockchain technology represented by the contract) is 2.0

94. Blockchain 3.0

In the era of intelligent Internet of Things, it goes beyond the financial field and provides decentralized solutions for various industries. Solution

95. Smart Contract

Smart Contract is a computer protocol designed to spread, verify or execute contracts in an information-based way. Simply put, electronic contracts are determined in advance. Once the contract is confirmed by both parties, the contract will be 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.

97. The difference between big data and blockchain

Big data is the means of production, AI is the new productivity, and the 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. Simply understood, 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)

98. What is ICO?

ICO, Initial Coin Offering, is the initial public offering of tokens, which is crowdfunding in the blockchain digital currency industry. 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: 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.

103. What is a contract transaction?

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.

104. Digital Currency Industry Chain

Chip manufacturers, mining machine manufacturers, and mining machine agents mine and export to exchanges for retail investors to speculate in coins< /p>

105. Who is Bei Feng?

Beifeng: Digital currency value investor

Investment style: Steady

106. Build a community?

Beidou Community (high-quality price investment community)

Combining long and short, focusing on price investment, no contracts, no short-term play< /p>

Reasonable layout, scientific operation, prudent and conservative, earning periodic money

Welcome currency friends and seek common development.

3. What do we need to know to learn blockchain

First we need to understand the relevant content of network communication, followed by data storage, encryption technology, consensus mechanism and security technology, and finally Cross-chain technology and chainDown technology. I personally think that learning about blockchain should start from practice. If you are a programmer, you can go to a blockchain-related company to get in touch with related businesses and learn on the job. I used to work at Xuanling Technology, and the company’s strength and experience in blockchain development are very good, making it a good candidate for both work and cooperation.

4. How to do blockchain

It is necessary to establish the data layer, network layer, consensus layer, incentive layer, contract layer and application layer.

1. The data layer encapsulates the underlying data blocks and related data encryption and timestamps and other basic data and basic algorithms;

2. The network layer includes distribution

3. The consensus layer mainly encapsulates various consensus algorithms of network nodes;

4. The incentive layer integrates economic factors Into the blockchain technology system, it mainly includes the issuance mechanism and distribution mechanism of economic incentives;

5. The contract layer mainly encapsulates various scripts, algorithms and smart contracts, which is the programmable feature of the blockchain The basis;

6. The application layer encapsulates various application scenarios and cases of the blockchain.

(4) Extended reading on the sequence of development of blockchain projects

General Secretary Xi Jinping emphasized during the 18th collective study session of the Political Bureau of the CPC Central Committee, “Take blockchain as the core "An important breakthrough for independent technological innovation" and "accelerating the development of blockchain technology and industrial innovation."

The forward-looking judgment of the Party Central Committee has brought "blockchain" into the public eye and has become a common concern for financial capital, the real economy and social public opinion.

From network power to big data, from media convergence to blockchain, the Political Bureau of the CPC Central Committee has collectively studied and aimed at the forefront of technological change, demonstrating the direction, forward-looking judgment and future foresight of the Party Central Committee, leading It follows the pace of China's industrial reform and economic transformation. This collective study by the Political Bureau of the Central Committee specifically emphasized "blockchain", which opened up imagination space for the development and application of blockchain.

From a technological perspective, blockchain involves many scientific and technical issues such as mathematics, cryptography, Internet and computer programming. From an application perspective, simply put, blockchain is a distributed shared ledger and database, which has the characteristics of decentralization, non-tampering, full traceability, traceability, collective maintenance, openness and transparency.

These characteristics ensure the "honesty" and "transparency" of the blockchain and lay the foundation for the blockchain to create trust. The rich application scenarios of blockchain are basically based on the ability of blockchain to solve the problem of information asymmetry and achieve collaborative trust and consistent action among multiple subjects.

5. 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 There are records of currency transactions, that is, ledgers;

② Disadvantages of centralized institution accounting - tamper-proof; easy to change

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

1.2 Hash function (encryption method)

① Function: Convert a string of any length into a 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 , no application is required to obtain it, and 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 style verify (Zhang San’s address, transfer information: Zhang San transfers 10 yuan to Li Si, signature of this transfer) = True

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

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, one person is selected from all accounting nodes in a certain way, and his transaction pool is used as the next block and broadcast to the entire network.

Other nodes are based on the latestFor transactions in the block, delete the transactions that have been recorded in your own transaction pool, 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#

6. How to develop blockchain and what is needed to develop a digital currency exchange

< p>Hello, what you want to ask in this question is how to develop blockchain? Or how to develop a digital currency exchange? Blockchain is a technology and a new application model of computer technologies such as distributed data storage, point-to-point transmission, consensus mechanism, and encryption algorithms. Developing a digital currency exchange requires the use of blockchain technology. Here is a general process for your reference:

Choose a jurisdiction that suits your needs and budget.

Open your company and open a company bank account (the account is for business transactions, not for the storage of client funds).

Deposit funds into your digital currency exchange.

Purchase/develop digital currency exchange system.

Create a token or coin that can be traded with BTC, ETH, etc. Support multiple digital currency trading pairs, multiple legal currency transactions, the more trading pairs can be provided,

Establish a compliance system and keep relevant records, such as: KYC, AML, etc.rule.

Hire employees who focus on compliance and banking business (in addition to the original marketing staff, additional hires are required), conduct self-regulation, and prepare for future application for international licenses.

Apply or negotiate to obtain a digital currency license in the region where you will operate. Currently, many well-known digital currency exchanges have not obtained licenses.

Establish a debit card or other withdrawal system to facilitate exchange users to withdraw money without using wire transfer.

Create a USD-backed pegged token (similar to USDT) that can be stored in an electronic wallet or used for trading. The main purpose of this anchored token is to reduce transaction fees caused by users' wire transfers or exchange withdrawals. The pegged token needs to be fully reserved in a U.S. bank.

Apply for digital currency licenses in certain jurisdictions where your customers are located. That is, if you plan to list in the UK, you will need to obtain a UK license.

Open a bank account specifically for handling user funds.

Of the above tasks, the most difficult is step 12 - opening a bank account dedicated to handling user funds. The preparation work from step 1 to step 11 is crucial to step 12. The improvement of preparation work will help you successfully obtain a bank account. Currently, about 80% of assistance requests are related to the final opening of a bank account specifically for handling user funds. . If you do not have your own development team to develop a digital currency exchange, it is recommended that you choose a professional service provider like MasterDAX, which is very helpful in terms of time and personnel costs.