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1 ID based on Ethereum

Publish: 2021-05-17 09:45:12
1.

what is Ethereum:

Ethereum is an innovation based on the application of technologies and concepts in bitcoin to computers. Ethereum itself imitates a lot of bitcoin technology to maintain the computer platform. blockchain technology is one of them
Ethereum platform can safely run any program users want

advantages of Ethereum over other competitive currencies before Ethereum appeared, some digital currencies imitated bitcoin. However, these projects have their own shortcomings, they can only support one or several specific applications at the same time< However, the reason why Ethereum can surpass the limitations of these projects in the past is because of the core idea of Ethereum

what Ethereum wants to implement is a blockchain protocol with built-in programming language. Since it supports programming language, in theory, any blockchain application can be defined with this language, and then run on Ethereum's blockchain protocol as an application

The design of Ethereum is very flexible and adaptable

Ethereum target sets the advantages of blockchain technology, in order to add the advantages of blockchain, such as decentralization, openness and security, to almost all computing fields

blockchain applications of Ethereum

Ethereum has many blockchain applications, such as digital applications of gold and stocks, financial derivatives applications, DNS and digital authentication, etc

Ethereum has achieved more than 100 blockchain applications by many start-ups

Ethereum has also been closely watched by some financial institutions, banking consortia (such as R3), as well as large companies like Samsung, Deloitte, RWE and IBM. As a result, a number of blockchain applications such as simplified and automated financial transactions, merchant loyalty index tracking, and gift cards designed to achieve decentralization of electronic transactions have emerged

the relationship between Ethereum and blockchain:

Ethereum is a programmable blockchain

Ethereum does not give users a series of preset operations (such as bitcoin transaction), but allows users to create complex operations according to their own wishes

in this way, Ethereum can be used as a platform for various types of decentralized blockchain applications, including but not limited to cryptocurrency

like other blockchains, Ethereum also has a peer-to-peer network protocol. Ethereum blockchain database is maintained and updated by many nodes connected to the network. Each network node runs the Ethereum simulator and executes the same instructions. Therefore, people sometimes call Ethereum "world computer"

2. The digital currency

issued based on Ethereum public chain should be observed according to the price trend of the platform.
3.

Ethereum is an open source public blockchain platform with smart contract function. It provides decentralized virtual machine (Ethereum virtual machine) to process point-to-point contract through its special cryptocurrency ether (also known as "Ethereum")

The token on the

blockchain is called ether, and the code is eth. It can be traded in many foreign exchange markets of cryptocurrency, and it is also the medium used to pay transaction fees and computing services on Ethereum

the concept of Ethereum was first proposed by vitalik buterin, a programmer, from 2013 to 2014, inspired by bitcoin, with the general meaning of "next generation cryptocurrency and decentralized application platform", and began to develop through ICO crowdfunding in 2014. As of February 2018, Ethernet is the second highest cryptocurrency in market value, second only to bitcoin

extended data:

Ethereum platform has no characteristics and value. Like programming languages, it's up to entrepreneurs and developers to decide what to use. However, it is clear that some application types benefit more from the functions of Ethereum than others. Ethereum is especially suitable for those applications that automatically interact directly between points or promote group coordination activities across networks

for example, coordinate the application of point-to-point market, or the automation of complex financial contracts. Bitcoin enables indivials to exchange money without the help of financial institutions, banks or governments. The impact of Ethereum may be more profound

in theory, any complex financial activities or transactions can be automatically and reliably carried out on Ethereum with coding. In addition to financial applications, any application scenario with high requirements for trust, security and persistence, such as asset registration, voting, management and Internet of things, will be affected by Ethereum platform on a large scale

4. 1. What is the ether classic<

etc (Ethereum Classic) is a bifurcated currency that Ethereum hard bifurcates after 1920000 blocks, and its function is very similar to Ethereum. Etc adheres to the concept of decentralization and supports the consensus mechanism of blockchain guarantee. Etc firmly believes that once the blockchain starts to run, its development direction will not be controlled by any central team, but will be determined by the consensus of the people participating in the whole network and the consensus of the computing power of the whole network

the Ethereum blockchain hard branching in July 2016 aims to transfer the Dao funds stolen by hackers to an account controlled by investors, and let the old transaction records be forgotten by history. Most Ethereum developers are involved in the reversal, as are exchanges, startups and other members of the ecosystem. A few days later, the project returned to normal. But not everyone wants to forget the old record. As a result, a small number of miners continued to use the original blockchain as a protest. They described the hard fork as a capital withdrawal for the abandoned project of the Dao. So Ethereum classic (etc) was born

2. Detailed parameters

Chinese Name: Ethereum classic English Name: Ethereum classic English abbreviation: etc

developer: Ethereum Classic team core algorithm: ethash consensus proof: POW

release date: 2016 / 7 / 20 block time: About 15-17 seconds / block

total currency: fixed at 210 million, up to 230 million, Every 5 million blocks decelerate by 20%, and the first proction rection is expected to be in December 2017

main features: independent cryptocurrency
5. Ethereum is a distributed computing platform. It generates an cryptocurrency called ether. Programmers can write "smart contracts" on the Ethereum blockchain, and these Ethereum smart contracts will be executed automatically according to the code

what is Ethereum
Ethereum is often compared with bitcoin, but the situation is different. Bitcoin is a kind of cryptocurrency and distributed payment network, which allows bitcoin to be transferred between users

related: what is bitcoin? How does it work

Ethereum has a bigger goal. As Ethereum says, "Ethereum is a distributed platform running smart contracts.". These smart contracts run on "Ethereum virtual machine", a distributed computing network composed of all devices running Ethernet nodes

"distributed platform" means that anyone can set up and run an Ethereum node just as anyone can run a bitcoin node. Anyone who wants to run "smart contracts" on nodes must pay the operators of these nodes in ether, which is a cryptocurrency related to Ethereum. Therefore, the person running the Ethernet node provides computing power and gets paid in the Ethernet, which is similar to the way that the person running the bitcoin node provides hash power and pays in bitcoin

in other words, although bitcoin is only a blockchain and payment network, Ethereum is a distributed computing network, and its blockchain can be used for many other things. Details are provided in the Ethereum white paper

what is ether
Ethernet is a digital token (or cryptocurrency) related to Ethereum blockchain. In other words, Ethereum is the token and Ethereum is the platform. But now people often use these terms alternately. For example, coinbase allows you to buy Ethereum, which stands for Ethereum

this is technically "altcoin", which actually means a non bitcoin cryptocurrency. Like bitcoin, ether is supported by distributed blockchain - in this case, Ethereum blockchain

developers who want to create applications or Ethereum smart contracts on Ethereum blockchain need Ethernet token to pay for nodes to host it, while users of Ethereum based applications may need Ethernet to pay for services in these applications. People can also sell services outside the Ethereum network and accept Ethernet payments, or they can sell Ethernet tokens in cash - just like bitcoin
6. Ether clown is a new blockchain game recently. Its full name is cryptoclone, which is based on Ethereum blockchain
the specific playing method is like this.
the proction of clowns
the proction mechanism of clowns can be divided into two kinds, one is the official output, the other is the breeding output between two clowns< The appearance of a clown is composed of eight parts. The attributes of each part can be divided into common and rare. The number of rare attributes is less than that of common attributes, which makes the clown with rare attributes more precious
every clown is unique
> clown trading
etheric clown can be directly used for trading
sell: users can choose clowns to be auctioned in the market, and they can sell their own clowns
buy: the buyer selects the clown on sale in the market and pays ether to buy the clown he likes< There are four kinds of clown attribute values: growth value, strength value, agility value and wisdom value. Generation 0 clowns get the value of each attribute randomly, and the non generation 0 clowns are mainly inherited
attribute values can be changed by eating food
clown food and feeding
owners can buy spinach, beef, carrots, walnuts and other food through the mall to feed clown pets.
7.

During Iwasaki's lifetime, the Meiji government once purchased a steamboat for Mitsubishi company and provided supplementary funds to help the struggling Mitsubishi company. However, the Meiji Government prohibited Mitsubishi from developing any business other than shipping. The only exception is that the Meiji government also allowed Mitsubishi to develop maritime related businesses, such as coal mine development, which can be used for maritime transportation
mitaro has paid attention to Gao coal mine in Kyushu for a long time. The high island coal mine was first mined by the British, Gulliver. Gulefei is a famous "God of death", he is the director of Nagasaki agency of Jiading Madison company. In 1873, in order to avoid the manipulation of foreign capital, the Japanese government changed the mining instry to government-owned. It was later sold to Kojiro goto in September 1874. Houteng xiangerlang did not change his loose management attitude, and his debts became more and more. Finally, Fukuzawa Yukichi intervened and asked mitaro to buy Gao coal mine in March 1881. The mine later became Mitsubishi's cash cow at the same time as Jigang mine. Mitaro is very enterprising and actively expands his business scope. In July of that year, the meeting of promoters for the establishment of marine insurance companies was held in Tokyo. This was originally a kind of company set up by the former princes and civil servants to raise funds for Quanlu bonds (bonds issued in 1876 to compensate the salaries of the Chinese, gentry and other hereditary nobles). The general agent of the company was shizawa Rongyi. Seize's calculation is that Mitsubishi will be the company's biggest customer and must be wooed. He took the initiative to negotiate with mitaro. Mitaro had already felt the urgency of the marine insurance instry. Therefore, of the 600000 yen capital of Tokyo Marine Insurance Company, 110000 came from mitaro. Mitaro became the largest shareholder, but turned the marine insurance company into a company that he could control< In 1881, mitaro iwazaki founded Meiji Life Insurance Company, the first life insurance company in Japan. In addition, in order to better compete with the P.O. steamship company in the UK, mitaro, with the full support of his younger brother mitaro, started the Tokyo Osaka documentary finance business. In April 1880, Mitsubishi exchange, with a capital investment of 1 million yen, officially opened. Since then, mitaro has established Mitsubishi Bank on the basis of these companies
because the government has banned Mitsubishi from engaging in other businesses outside the shipping instry, mitaro has tried every means to set up and operate some promising companies in the name of subsidiary businesses of the shipping instry, which has laid the foundation for Mitsubishi to move towards enterprise alliance and "land kingdom" in various aspects. After the death of mitaro, mitaro's successors, in line with the spirit of Iwasaki, made Mitsubishi move step by step towards a large, organized and modernized enterprise alliance. Mitarao's first successor was his brother mitarao. After returning from studying in the United States, mitsuke immediately joined the Mitsubishi chamber of Commerce as the vice president to assist Mitsuro. In 1874, mitsuke married his eldest daughter, Zaomiao. In Mitsubishi's leadership, only mitarao has stayed abroad. Therefore, only mitarao can plan the company's strategy and strategy in a new way of thinking. Mitarao attaches great importance to him. When mitsuke became president, the Mitsubishi chamber of Commerce was in an extreme predicament. As mentioned earlier, mitsuke boldly decided to merge his shipping company (the main body of Mitsubishi chamber of Commerce) with the joint company to establish Japan Post shipping company, and skillfully transferred the control of the new company from the other party to the hands of Mitsubishi first generation
because the main body of Mitsubishi, namely the shipping company, has been separated, mitsuzuki is preparing to transform "Mitsubishi of the sea" into "Mitsubishi of the land" on the basis of the coal mining instry, copper mining instry and shipbuilding instry of the former subsidiary Mitsubishi. He changed the name of the original Mitsubishi company to Mitsubishi society. At the same time, because the address of the original company had been transferred to Japan Post shipping company, mizuke also moved the headquarters of the new company to hamamachi, Lingan island near yutanakawa, and then applied to the official for business registration again
mizuke made a rule for the new company Mitsubishi: the company's staff's advance and retreat and business execution, regardless of the size of the matter, are all decided by the president, and employees are not allowed to make their own decisions. This completely inherited the concept of "one enterprise" and the organization of "President dictatorship" in the "company regulations" formulated by mitaro. However, in the actual operation, mitsuke's practice is different from that of his brother mitaro. He is better at listening to the opinions and suggestions of his subordinates than mitaro. He is not so arbitrary as mitaro
the Gao coal mine purchased in the mitarao era is the pillar of Mitsubishi society. In 1889, mitsuke bought Xinru coal mine and LiuTian coal mine, then operated Zhufeng coal mine, and applied the new technology of coal mining and transportation to his coal mine business. In addition to coal mining, mitsuke is also committed to the operation of metal mining. He bought mining instries such as weiquze, Shengye, zou, Qifeng and miangu, and laid tunnels and rails for them. He used Balton water wheel, Hamilton mill, water jacket smelting furnace and other facilities. It is precisely because he boldly promoted various technological innovations and improved proctivity. Finally, the coal and copper mining instry will become the largest source of income for Mitsubishi in mizuke era
Mi Zhizhu was not satisfied. He used the income from mining to invest in shipbuilding. In 1884, the Japanese government rented the Nagasaki shipyard, which had been in deficit, to Mitsubishi. At that time, the Meiji government, which was partial to Mitsubishi (Mitsubishi's rival), rented Nagasaki shipyard to Mitsubishi, not to help Mitsubishi, but to send a burden to Mitsubishi to weaken the competitiveness between Mitsubishi and Mitsubishi< In June 1884, Mitsubishi decided to lease Nagasaki shipyard. Three years later, mitsuke applied to the government to stop the lease and buy the shipyard directly. He hoped to take shipbuilding instry as the core business of revitalizing Mitsubishi society
the Meiji government quickly approved the application of Mizuki, because the Meiji government has invested 1.13 million yen in Nagasaki shipyard, and there is no sign of turning from loss to profit. Now, Mitsubishi is willing to buy it for 450000 yen. Why not? Mizhu was not impulsive to buy the shipyard either. He skillfully negotiated with the government to obtain the transfer right of the shipyard by paying 459000 yen in five years, and then applied for the return of the shipyard with 10% interest per year in cash, that is, 910170 yen per year. In this way, Mitsubishi can find a big bargain. Mizuki made Nagasaki shipyard "the largest shipyard in the East". Kobe shipyard was opened in 1905. At that time, it was said that mitsuke "mastered the Japanese postal and shipping company with his right hand, set up a shipyard with his left hand, and absorbed the capital of the shipping instry. The skill is really amazing."
in addition to the mining and shipbuilding instries, the banking instry has also been the focus of mizuke. After the merger of Mitsubishi's shipping company and joint company, the Japanese government changed its previous policy towards Mitsubishi and allowed it to develop in the banking instry. At that time, the banks were all known as national banks. In fact, they were purely private banks, but they did not have the right to issue silver coins. Later, because of the change of conditions, the national bank can obtain huge benefits. As a result, a total of 151 banks sprang up to issue banknotes, causing great confusion. At that time, the 119th and 49th banks were on the verge of bankruptcy, so they asked for help. As the investors of the two banks were founded by a group of old samurai, mizuke, who was born in a declining Samurai family, was said to have deep sympathy for this and had a "chivalrous heart" to save people, so he took over the business. Of course, although he is bold, he is not careless. He predicted that the prospect of the banking instry is very good, and calculated the careful plan after taking over, and then began to take action. He took the commodities deposited in Mitsubishi Tokyo warehouse company as guarantee to carry out "commodity guarantee finance", which ensured the bank's profit
mitsuke later appointed his prudent and capable cousin, Liangping FengChuan, as the chairman of the bank. Not only was he very active in the financial circles, but most of the famous Japanese politicians at that time were his friends. At the same time, he also insisted on the policy of helping others, and dared to seek development cautiously in the face of difficulties and dangers. Therefore, even after 1895, the Bank of Mitsubishi was more stable than other banks and got rid of the trouble quickly
mining, shipbuilding and banking are the three pillars of Mitsubishi's revitalization. On this basis, mitsuzuki has continuously expanded its business to real estate, comprehensive business, railway, electric machinery, heavy instry, paper making, glass, beer, etc
in Marunouchi, in front of the imperial residence in Tokyo, Japan, there are many buildings of Mitsubishi society. The place used to be a training ground full of weeds. The Japanese government sold it to Mitsubishi in 1889. The land of 135000 square meters sold for 1.5 million yuan, so each square meter is worth about 11 yuan and 10 cents. At that time, the highest land price was Qu Ting, which was only 2.34 yuan per ping. Because the price is exorbitant and the land is sold in bulk, no one will pay attention to this land. However, when he was young, mitsuke, who had traveled abroad and seen many beautiful metropolises, had his own plans in mind. He bought the land quickly. Many people are either surprised or sneer at the decision of mitsuzuki: "what's the use of buying such a large piece of land?" Mi Zhizhu just gave a faint smile to these people, or casually replied: "no purpose, just want to grow bamboo and raise tigers." Having said that, he was not idle. Mitsuzuki started to build a modern office building in this area called "the origin of Mitsubishi". He abandoned the traditional wooden houses in Japan and replaced them with stone, brick and other western building materials. In terms of the folk customs at that time, it was a pioneering work for the first time. Later, the office street was named "one London". The beautiful red bricks used in the building not only attract people from Tokyo, but also visitors from all over the world. In addition, mizuke also invested in the new land of Haipu in Ji Bay of Gangshan, the forest planting of ganyeyinfan and the farmland of Niigata. He also partnered with others to buy a large plain in the Iwate mountain area, and named it after several people. Mizuke's attention to land became the foundation for the formation of Mitsubishi real estate. Mizuke is also interested in investing in railways. Most of the railways in Japan today were laid by civilians in the Meiji era. In addition to the Japanese railway developed in mitarao's time (today's northeast line in Japan), mitarato also invested in the construction of Shanyang Railway (Shanyang line) and Kyushu Railway (Kagoshima line and Nagasaki line). The railway instry can not only transport coal mines, but also be the main consumers of coal mines
mizuke pays special attention to improving the technology made in Japan. Under the guidance and support of mizuke, Nagasaki shipyard has made full efforts to manufacture the first turbine made in Japan. Due to the appearance of steam turbine made by Nagasaki shipyard, Mitsubishi internal combustion engine manufacturing instry and Mitsubishi Electric Instry soon separated from shipbuilding instry, and graally formed Mitsubishi Heavy Instry< As early as 1889, mizuke was optimistic about the development of paper instry. He first sponsored the Kobe paper mill company set up by the Washoe brothers, and later bought that company, which is the origin of Mitsubishi paper instry. Mizuke sent his third son, junmi, to London to study applied chemistry. After returning home, mizuke founded a glass instry,

8. Ethereum is also a proct of blockchain 2.0, which is an open intelligent contract complete solution. Bitcoin is the most important application of blockchain 1.0, which completes currency and payment transactions well. But when we need to record and transfer more complex asset types, we need the third step - a more powerful scripting system - to finally achieve Turing completeness (the ability to run any currency, protocol or blockchain). Ethereum is a blockchain based project, which aims to provide a Turing complete scripting language and Turing complete platform

blockchain 1.0 mainly refers to bitcoin. Blockchain 2.0 extends to all assets, while blockchain 3.0 goes beyond currency, finance, even commerce, and all areas of our lives, including politics, social relations, ecation, medical care, etc. According to the prediction and conception of people in the instry, the era of blockchain 3.0 will be realized in the next five years. At that time, blockchain will be recognized and accepted by all the public like the Internet, thus completely subverting our lives

McKinsey has submitted a technical report on blockchain to the Federal Insurance Advisory Committee of the United States. The report calls 2009-2016 the "Dark Age" and believes that all blockchain solutions ring this period are based on bitcoin, and the new era of blockchain will begin in 2016. At that time, the application of blockchain will become unprecedented. Applying an original sentence in McKinsey report: Based on the current development speed of blockchain, we believe that blockchain solutions may realize their full potential in the next five years.
9. This is a trend now. Blockchain is the next era that is about to enter. There is also a game in the blockchain called ether clown, in which there are clowns who can work to make money, also known as cryptoclones. It is a digital blockchain game with collection value developed based on Ethereum blockchain. Using ether money to adopt clowns can be resold, and they can also be used to breed a new generation of clowns with strange shapes. They can also be cultivated to work and earn money, which makes the digital collection of clowns more sustainable and playable. This is a way to make a real game, let players get a more comfortable experience, and combine with blockchain technology to ensure the interests of players
with the well-known proct form of games, we will spare no effort to promote blockchain technology and bring human beings into the era of full intelligence. It can be said that this is the beginning of an era. Hurry to join us
10.

Transaction

the behavior of blockchain transaction follows different rule sets

< UL >
  • e to the distributed and unlicensed nature of public blockchain, anyone can sign the transaction and broadcast it to the network

  • according to different blockchains, traders will be charged a certain transaction fee, which depends on the needs of users rather than the value of assets in the transaction

  • blockchain transactions do not require any central authority verification. It only needs to use the digital signature algorithm (DSA) corresponding to its blockchain to sign it with the private key

  • once a transaction is signed, broadcast to the network and mined into a successful block in the network, the transaction cannot be recovered

  • Ethereum transaction structure

  • Ethereum transaction data structure: transaction 0.1 eth

    {
    & 39; nonce':&# 39; 0x00', // Decimal: 0
    & 39; gasLimit': &# 39; 0x5208', // Decimal system: 21000
    & 39; gasPrice': &# 39; 0x3b9aca00', // Decimal system: 10000000000
    & 39; to': &# 39;&# 39; ,// Sending address
    & 39; value': &# 39; 0x16345785d8a0000',// 100000000000000000 ,10^17
    ' data': &# 39; 0x', // Decimal representation of null data; chainId': 1 / / blockchain network ID
    }

    these data have nothing to do with the transaction content, but have something to do with the execution mode of the transaction. This is because when you send a transaction in Ethereum, you must define some other parameters to tell miners how to handle your transaction. Transaction data structure has two attribute designs & quot; gas": & quot; gasPrice",& quot; gasLimit"

  • " gasPrice": The unit is Gwei, which is 1 / 1000 eth, indicating the transaction cost

  • & quot; gasLimit": The maximum gas charge allowed for the transaction

  • these two values are usually filled in automatically by the wallet provider

    in addition, you need to specify which Ethereum network to execute the transaction (chainid): 1 represents the Ethereum main network

    ring development, tests are usually carried out locally and on the test network, and transactions are carried out through the test eth issued by the test network to avoid economic losses. After the test, enter the main network transaction

    in addition, if you need to submit some other data, you can use & quot; data" And & quot; nonce" Attach as part of a transaction

    a nonce (number used only once) is the value used by Ethereum to track transactions, which helps to avoid double spending and replay attacks in the network

  • Ethereum transaction signature

    Ethereum transaction involves ECDSA algorithm. Taking JavaScript code as an example, the popular ethers.js is used to call ECDSA algorithm for transaction signature

  • const ethers = require(' ethers')
  • const signer = new ethers.Wallet(' Wallet address

  • signer.signTransaction({

  • ' nonce':&# 39; 0x00', // Decimal: 0

  • & 39; gasLimit': &# 39; 0x5208', // Decimal: 21000

  • & 39; gasPrice': &# 39; 0x3b9aca00', // Decimal 10000000000

  • & 39; to': &# 39;&# 39; ,// Sending address

  • & 39; value': &# 39; 0x16345785d8a0000',// 100000000000000000 ,10^17

  • ' data': &# 39; 0x', // Decimal representation of null data

  • & 39; chainId': 1 / / blockchain network ID

  • })

  • . Then (console. Log)
  • you can use the online application composer to deliver signed transactions to Ethereum. This is known as "offline signature.". Offline signatures are particularly useful for applications such as status channels, which are smart contracts that track the balance between two accounts and transfer funds after a signed transaction is submitted. Offline signature is also a common practice in dexes

    you can also use online wallet to create signature verification and broadcast through Ethereum account

    with Portis, you can sign a transaction to interact with the gas station network (GSN)

    < / UL >

    the Xueshuo innovation blockchain Technology Workstation of Lianqiao ecation online is the only approved "blockchain Technology Specialty" pilot workstation of "smart learning workshop 2020 Xueshuo innovation workstation" launched by the school planning, construction and development center of the Ministry of ecation of China. Based on providing diversified growth paths for students, the professional station promotes the reform of the training mode of the combination of professional degree research, proction, learning and research, and constructs the applied and compound talent training system

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