🤝Foreword

At present, the world economy is being dragged down by factors such as the epidemic, inflation, and geopolitical conflicts, and the downside risks have intensified. The developed economies accelerated the tightening of monetary policy in order to curb inflation, and the spillover effect made emerging and developing economies worse.

At present, it is difficult to accurately predict the impact of the epidemic on the global economy, but due to concerns about the extreme vulnerability of the global supply chain and the fear of rising systemic risks, economic globalization has also been infected, and may become the most important factor in this epidemic. long-term victim. The new crown epidemic has accelerated global challenges and the need for international cooperation. However, conflicts between Russia and Ukraine, unilateralism, geopolitics and trade frictions have continuously led to the continued deterioration of the entire situation. This global epidemic seems to be testing human social mechanisms, the world's post-war order, and humanity all aspects.

There is no doubt that global solidarity and cooperation are the key to our victory over this human crisis. Cooperation and consensus are the most important parts of the development of human civilization. Without trust there is no cooperation, and without transparency there is no consensus. We have to admit that the centralized social mechanism has greatly promoted human civilization for thousands of years. However, with the growth of the global population, the earth's resources are gradually scarce, the natural environment continues to deteriorate, and the conflict between the rich and the poor is also intensifying. This makes us have to rationally reflect on the centralized world, so the Internet came into being. In 1957, the Soviet Union successfully launched the first artificial earth satellite, Sputnik.

In response, the U.S. Department of Defense (DoD) during the Cold War established the Advanced Research Projects Agency (ARPA) and began to apply science and technology to the military field. In 1969, the Internet was born in the Pentagon of the United States, also known as the Internet (Internet). Its predecessor is the ARPAnet developed under the auspices of the US Defense Advanced Research Projects Agency (ARPA). In order to prevent self Since its own computer network was attacked and destroyed, the United States built a military "ARPAnet" (ARPAnet), which was the predecessor of the Internet.

By the 1970s, ARPAnet consisted of dozens of non-communicating computer networks. For this reason, ARPA has set up a new research project, and wants to use a new method to interconnect different computer LANs to form the "Internet". In 1974, TCP/IP, a network protocol for connecting packets, appeared. In 1982, ARPA accepted TCP/IP and selected the Internet as the main computer communication system. In 1986, the National Science Foundation (NSF) of the United States interconnected five supercomputer centers serving scientific research and education to form NSFnet. Within two years, NSFnet replaced ARPAnet as the Internet The backbone network of the network, and allows networks of universities, government or private scientific research institutions to join. By 1989, ARPAnet disbanded, and the Internet completely shifted from military use to civilian use. On March 12, 1989, British computer expert Tim Berners-Lee (Tim Berners-Lee) Wrote a report on the establishment of a system for transmitting hypertext over the Internet, and the World Wide Web was born, abbreviated as WEB is a way to access information through Internet media and is also a part of the Internet. the following year, Tim Berners-Lee developed the world's first web browser, WorldWideWeb (later renamed Nexus) and the first web server httpd.

At the same time, the most basic web standards have been established, including URLs,HTML and HTTP. On August 6, 1991, the world's first web page (http://info.cern.ch/) went online. The rapid development of the Internet has aroused great interest from merchants. In 1992, three American companies, IBM, MCI, and MERIT jointly established an advanced network ANSnet, which became another backbone network of the Internet. On April 30, 1995, NSFnet, established with state funding, announced that it would cease operations. At this time, the backbone network of the Internet has covered 91 countries around the world, with more than 4 million hosts. By 2000, the Internet It developed at an astonishing speed, and soon reached an unprecedented scale.

Nowadays, the Internet has entered thousands of households and has become integrated into our lives like air, water, and electricity, and is indispensable. The Internet has been called the greatest invention of mankind in the 20th century. It is a decentralized network connecting millions of computers, each of which is independent and can be accessed in multiple ways, with more than 3.5 billion users worldwide. The formation and development of the Internet has changed the way the world exists and information dissemination, people's way of life and way of thinking, and become the main direction of future development. Through the Internet, people can see the whole world and speak freely. Human beings have more cyberspace and freedom than ever before.

In order to realize the ideal of Internet freedom and Internet decentralization, the inventor of the World Wide Web, Tim Berners-Lee, Giving the world wide web free access to the world. Recently, in an interview with the media, he commented on the conclusion of the social experiment of the Internet Disappointed with the results and the state of the Internet today. After more than 20 years of rapid development, the Internet has Monopolized by the government and business oligarchy, it has even become a tool for some interest groups to maintain their vested interests. On November

2008, a person named Satoshi Nakamoto posted on the P2P "Bitcoin: A Peer-to-Peer Electronic Cash System" (Bitcoin: A Peer-to-Peer Electronic Cash System), describing his new vision for electronic money. bits Coins were born. On January 3, 2009, the creation block of Bitcoin was born. On January 9, the block with serial number 1 appeared and connected with the creation block with serial number 0 to form a chain, marking the birth of blockchain .

During the development of the blockchain in the past ten years, it has had a great impact on politics, economy and culture. Melanie Swan, founder of the American Institute of Blockchain Science, divided the development stages of blockchain into blockchain 1.0 era, blockchain 2.0 era and blockchain In the 3.0 era, we can clearly see the current status and future of the blockchain along these three eras.

Blockchain 1.0 Era The birth of Bitcoin is a sign of the blockchain 1.0 era. During this period, the development of blockchain technology is closely related to digital currency, and its applications generally focus on currency transfer, exchange and payment. In a sense, the blockchain technology of this period has found a solution to the decentralization of currency and payment. Bitcoin is a P2P form of digital currency, and point-to-point transmission means a decentralized payment system. After Satoshi Nakamoto proposed the concept of "Bitcoin" and issued it publicly, it became the source of everyone's research on the blockchain. In the blockchain 1.0 era, the main innovation is the creation of a decentralized, open and transparent ledger of transaction records, whose database is shared by all network nodes, updated by "miners" and maintained by the whole people. No one can control this ledger . This technology has had as much impact on the financial industry as the invention of double-entry bookkeeping.

Features of the blockchain 1.0 era:

• (1) Data layer: chained data block structure with blocks as the unit The so-called chain data block structure means that the data blocks in the system are linked in an orderly manner by stamping time stamps, and after being processed by cryptography and other technical means, they are connected in an orderly manner in an end-to-end manner. When a new block is generated and needs to be packaged and uploaded to the block system, the nodes in the system need to share the hash value of the previous block of the new block, the current timestamp, valid transactions that occurred within a period of time, and their Merk Pack and upload content such as the Ershu root value, and broadcast to the entire network. Since each block is connected to the previous block, as the length increases, all previous information must be reconstructed to modify the transaction information of the blockchain, which is almost impossible, thus ensuring The security of ledger information is ensured.

• (2) Fully shared ledger: to ensure the authenticity of the ledger information In the blockchain network, the information recording historical transactions is passed to each node, and each node can own and store a complete and consistent transaction ledger. Even if the ledger data of individual nodes is changed or attacked, it will not affect the security of the general ledger. In addition, since the nodes of the whole network are connected by point-to-point Continuing, there is no single centralized server, so there is no single entry point for attacks. At the same time, the feature of fully shared ledger also effectively prevents the possibility of double payment.

• (3) Asymmetric encryption: Asymmetric encryption algorithm is an important application of blockchain, which builds the security defense system of Bitcoin through the combination of public key and private key.

• (4) Source code open source: The consensus mechanism and rules set in the blockchain network can be verified through consistent, open source source code. These characteristics lay the foundation for the development of blockchain. In addition, blockchain technology's solution to the "double spending" problem is also the key to the successful application of Bitcoin. For the "double spending" problem, how to avoid digital assets being reused? Satoshi Nakamoto made the following settings in the Bitcoin white paper:

1. The new transaction is broadcast to the whole network, so that every node in the network knows that a transaction has occurred.

2. Each node packs the received transaction information into a block.

3. Each node tries to find a proof of work with sufficient difficulty in its own block to obtain priority broadcasting rights.

4. When a node finds a proof of work, it broadcasts to the entire network.

5. If and only if all transactions included in the block are valid and have never existed before, the rest of the nodes agree on the validity of the block.

6. The approved blocks will be connected to the system and linked with other blocks on other chains to continuously extend the length of the chain. Due to the tamper resistance of the blockchain, after a new block enters the system, if you want to change the information on the block, you must change all the previous information to ensure the security of the blockchain. In the Bitcoin system, a transaction will be irreversible after being confirmed six times in a row, which is the principle of "six confirmations are irreversible". After a transaction data is packaged into a block, it is confirmed once, and the transaction information will permanently exist on the blockchain after six consecutive reciprocations. Because each confirmation takes a certain amount of time, the time-consuming of six confirmations is naturally longer. In this case, trying to use one fund for two payment transactions, due to the long confirmation time, it is impossible for the latter transaction to be confirmed at the same time as the previous transaction, and this fund is in the first transaction After the transaction confirmation is valid, the second transaction cannot be confirmed, thus effectively avoiding the "double spending" problem.

7. Real application in the era of block 1.0 Currency and payment constitute the most significant application in the block 1.0 era. A series of virtual currencies represented by Bitcoin have emerged, such as Litecoin, Dogecoin, Ripple, Futurecoin, Dotcoin, etc., which have been produced around the world. There are thousands of digital currencies, and there are about 700 kinds of them that are still in operation. These "alternative currencies" are full of In front of the "cash" on the Internet, another world in the financial field has been opened. In the application scenario of virtual currency In this way, individuals can distribute and trade various assets among individuals in a decentralized and global manner resources. The blockchain of this period has set off a huge wave in the financial field. In connection with transfer remittance and digital payment In related fields, blockchain technology has attracted much attention. The traditional way is to open an account through a central institution such as a bank, The cumbersome processing process of mobile banks, liquidation organizations, overseas banks (correspondent banks or overseas branches), etc., time The long-term cost is high. After applying blockchain technology, payment can realize end-to-end transactions, removing the cumbersome intermediate The institutional processing link is not only fast, but also has very low transaction costs. Especially in terms of cross-border payments, the blockchain-based payment system can provide users with global cross-border, real-time payment and settlement services in any currency, and cross-border payments will be completed instantly at low cost.

8. Blockchain 2.0 EraFeatures of the blockchain 2.0 era If blockchain 1.0 solves the problem of currency and payment decentralization, then blockchain 2.0 solves the problem of market decentralization. The key word in this period is "contract". Therefore, in the economy, market Blockchain technology has been fully applied in fields, finance, etc., such as in stocks, bonds, futures, loans, mortgages, property rights, smart assets and other fields. The advancement of blockchain 1.0 to 2.0 is to some extent a process of advancing Satoshi Nakamoto's original design concept of blockchain. Regarding the development path of the blockchain, Satoshi Nakamoto mentioned in a public email in 2010: "I have been thinking about whether Bitcoin can support multiple types of transactions, including escrow transactions, debt contracts, and Three-party arbitration, multi-signature, etc. If Bitcoin can develop on a large scale in the future, then these types of transactions will be what we want to explore in the future, but these transactions should be considered at the beginning of the design, so that it will be possible in the future.” Following the original setting, blockchain technology continues to evolve on the basis of Bitcoin. In the vision of Satoshi Nakamoto There are three core concepts in it: a decentralized end-to-end direct value transfer system for public transaction ledgers, a powerful scripting system to run any protocol or currency etc. Bitcoin realizes the first two, and the third technology Now it is reflected in Ethereum. It can be said that the emergence of Ethereum is a representative of the era of blockchain 2.0. The development of the period is closely related to the development of contract technology. About Ethereum. Ethereum is an open source public block with smart contract functions Chain platform, through its dedicated cryptocurrency Ethereum (Ether, referred to as "ETH") to provide decentralized Ethereum Ethereum Virtual Machine (EthereumVirtual Machine) to process peer-to-peer contracts. The concept of Ethereum was first proposed by programmer Vitalik Buterin between 2013 and 2014 after being inspired by Bitcoin, roughly meaning "the next generation of cryptocurrency and decentralized application platform", and began to develop through ICO crowdfunding in 2014. As of February 2018, Ethereum is the second-largest cryptocurrency by market capitalization, after Bitcoin. It can be defined as an open source block underlying system in which all blockchains and protocols can run. Like Bitcoin, Ethereum is not controlled by anyone and is jointly maintained by all participants on a global scale. This is like the Android system, which can provide users with a very rich API, allowing many people to quickly develop various blockchain applications on it. As of now, there are more than 200 applications on Ethereum. Smart contract is one of the prominent features of Ethereum, and it is the basic technology of programmable currency and programmable finance. The concept of "smart contract" was first proposed by cryptographer Nick Szabo in 1995. This concept can be simply understood as: a series of promises defined in digital form. Once the contract is established, the principle of smart contracts can be automatically executed on the blockchain system without the participation of a third party, which fully embodies the Always believe in "code is law". Although the time for this theory to be put forward is not too short, smart contracts were not widely used until the emergence of Ethereum, which provides provides a friendly, programmable base system. The prerequisite for the smooth execution of smart contracts is that the content of the established contract cannot be tampered with, and the execution process must Open, transparent and trustworthy. After the blockchain technology comes out, decentralization, tamper-proof, collective maintenance, and Features such as traceability become the natural symbiotic environment of smart contracts. Based on this, when the new generation represented by Ethereum After the blockchain application is closely integrated with the smart contract, the blockchain technology can be improved again. On Ethereum, a After a smart contract is created, it relies on the program to execute automatically, and no one can stop it from running. The smart contracts on the square can control various digital assets in the system and perform complex algorithms and operations. In terms of function, Ethereum has built a general-purpose, excellent underlying protocol that provides Turing's complete scripting language, and can write smart contracts to execute on the system. Here, we need to understand a basic concept: Turing is complete, that is, a programming language that can theoretically solve any algorithm. To support smart contracts, there are two types of account addresses on Ethereum: one is a common account, and the other is a contract account. The common account is similar to the account of the Bitcoin network, and the contract account is mainly used for smart contracts. From the operating principle of Ethereum, we can see that blockchain provides a trusted execution environment for smart contracts, and smart contracts facilitate the extended application of blockchain. Over time, the application of this technology goes beyond currency, extending to a wider field and having greater compatibility.

9. Practical applications in the blockchain 2.0 era Thanks to the open source program environment and the application of smart contracts, the blockchaindeveloped rapidly. Its application range has gone beyond currency, extending to futures, bonds, hedge funds, private equity, stocks, annuities, crowdfunding, options and other financial derivatives. In addition, with the combination of notarization documents, intellectual property documents, asset ownership documents and other electronic processes with the blockchain, tangible or intangible assets have found a possible operating environment on the blockchain. On the blockchain represented by Ethereum, people can write asset codes and create new blockchain assets. Simply put, you can issue your own blockchain tokens, and you can decide what kind of issuance mechanism to use, what the name of the token is, how much to issue, and how to issue it. At the same time, it is also possible to create the functions of blockchain assets by writing the code of smart contracts, such as voting, betting, conditional contracts, etc. Although blockchain-based smart contracts are still in their infancy, their potential is clear. We can imagine that one day in the future, tangible assets such as real estate and cars under people's names will enter the blockchain in the form of data, and a will will be generated in the form of a contract: The will procedure is triggered, and these assets will be automatically transferred to the heirs according to the will of the testator without the need for third party rulings such as courts or lawyers. At that time, perhaps the lawyer's business will also undergo a great change, from adjudicating contracts to creating smart contract templates on the blockchain, and people will carry out various point-to-point business activities based on smart contracts. At that time, people will no longer have to worry about breach of contract, fraud, etc. due to human greed, and the smart contracts that exist on the blockchain with codes and programs will not be manipulated by anyone, and the machine "judge" will be objective and fair execute the established contract. To put it simply, in the blockchain 2.0 era, the blockchain technology carrying smart contracts will give full play to the function of a decentralized transaction ledger, which can be used to register, determine and transfer various types of assets and contracts. However, the current blockchain 2.0 era is still in its early stages. Many applications are still based on ideas, and the application has not yet formed a large scale. Most projects still need to be verified by time. However, its broad application prospects have attracted the attention of the United States, China, Israel and most European countries and invested heavily in research. Experts predict that the blockchain 2.0 era will be the era of blockchain explosion. 3. Blockchain 3.0 Era The era of blockchain 3.0 is also the era of comprehensive application of blockchain, thus building a large-scale collaborative society. In addition to financial and economic aspects, the application of blockchain in social life at this time is more extensive, especially in the fields of government, health, science, culture and art. Before discussing the blockchain 3.0 era, let’s understand a few concepts: Dapp, DAC, DAO, DAS Dapp (Decentralized application): Decentralized application DAC (Decentralized Autonomous Corporation): Decentralized autonomous company. DAO (Decentralized Autonomous Organization): Decentralized Autonomous Organization. DAS (Decentralized Autonomous Society): Decentralized autonomous society. The application evolution of blockchain can be said to be a development history from Dapp to DAC and DAO, and then to DAS step by step. When blockchain technology is applied to social governance, we have entered the era of blockchain 3.0. It is conceivable that for an intelligent government system built on the blockchain, it can carry public affairs such as storing citizen identity information, managing national income, allocating social resources, and resolving disputes. In this system, citizen-related information such as land deeds, registered businesses, marriage registration, and health record management are properly preserved and processed. When a baby is born, the doctor uploads the child's birth date and other information to the blockchain citizen electronic identity system. After the system confirms the child's information, it will assign the child an ID. After the ID is confirmed by the relevant government departments, the relevant electronic identity Information will accompany the child's life. Thereafter, the child's school status, health, property, professional title, credit and other information will be linked to the ID and stored on the blockchain. When he passes away, the will contract related to him will be triggered, the relevant property will be distributed to his heirs, and no new information will be added to the information chain about him in the system.