Ethereum pre sold in Chengdu

1.

Buterin, the founder of Ethereum, is a Russian

at the end of 2013, vitalik buterin, founder of Ethereum, released the first edition white paper of Ethereum and launched the project. From July 24, 2014, Ethereum has carried out a 42 day pre-sale of Ethereum coins. In early 2016, Ethereum's technology was recognized by the market, and its price began to soar, attracting a large number of people other than developers to enter Ethereum's world. Two of China's three major bitcoin exchanges, huocoin.com and okcoin.com, both officially launched Ethereum on May 31, 2017

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extended materials:

in 2011, butrin began to realize bitcoin under the influence of his father when he was 17 years old in high school. Butrin showed a strong interest in this new thing. In order to better understand this fully distributed currency, butrin began to read bitcoin forum and technical materials. He wrote bitcoin blog articles to earn bitcoin, although his hourly salary was only $2 an hour

when he made 20 BTCs, he took 8.5 to buy a shirt. But he realized at that time that if thousands of people from all over the world join the bitcoin community, an independent financial system can be created, and the application of blockchain is not limited to cryptocurrency, but applicable to all walks of life. Since then, Butlin has been working in this direction

in late 2011, butrin graally became famous in the community. A man from Romania invited him to co-founder bitcoin magazine and serve as the chief writer

2.

There is an essential difference between Ethereum and bitcoin. What is the difference? Bitcoin defines a set of currency system, while Ethereum focuses on building a main chain (which can be understood as a road) to allow a large number of blockchain applications to run on this road

from this point of view, Ethereum's application scenarios are more extensive, which is why we say that Ethereum marks a simple monetary system in the era of blockchain

1.0, and a transformation to other instries and application scenarios in the era of blockchain 2.0

however, there is no perfect thing in the world. Although Ethereum has expanded the application scope of blockchain in all walks of life and improved the speed of transaction processing, it also has some disputes and doubts

first, the solution to the lack of scalability of Ethereum: slicing technology and lightning network

the bottom design of Ethereum, the biggest problem is that Ethereum has only one chain and no side chain, which means that all programs have to run on this chain equally, consuming resources and causing system congestion. Just like last year's very popular Ethereum game "encryption cat", when this game was very popular, it once caused Ethereum network paralysis

to improve the processing capacity, Ethereum proposes two ways: shard and lightning network. Let's introce these two technologies respectively

(1) fragmentation technology

vitalik buterin, founder of Ethereum, believes that the reason why mainstream blockchain networks such as bitcoin process transactions very slowly is that every miner has to process every transaction in the whole network, which is actually very inefficient. The idea of fragmentation technology is: a transaction does not need to be processed by all nodes in the whole network, as long as some nodes (miners) in the network are allowed to process it. Therefore, Ethereum network is divided into many pieces. At the same time, each piece can handle different transactions. In this way, the network performance will be greatly improved

however, the slicing technology is also controversial. As we all know, the important idea of blockchain technology is decentralization. Only when the whole network witnesses (processes) the same transaction can it have the highest authority. The Ethereum slicing technology is similar to the group witness, not all nodes witness together. In this way, it will lose the absolute "decentralization" attribute, and can only achieve the purpose of high performance by sacrificing certain characteristics of decentralization

(2) lightning network

lightning network uses the way of transaction under the chain. What does that mean? It means: when the participants of lightning network transfer money to each other, they do not need to confirm the transaction through the main chain of Ethereum, but create a payment channel between the participants and complete it under the chain

however, lightning network is not separated from the main chain. Before establishing a payment channel, you need to use the assets on the main chain as collateral to generate a balance proof, which indicates that you can transfer the corresponding balance. In the case that both parties of the transaction hold the balance certificate, both parties can make unlimited number of transfers under the chain through the payment channel

only when the off chain transaction is completed and the assets need to be transferred back to the chain, the balance change information of the main chain account will be registered on the Ethereum main chain, and no matter how many transactions occur ring this period, there will be no record on the main chain

another real benefit of lightning network is that it can save the cost of miners for you. At present, when we trade on the main chain of Ethereum, we need to consume gas and pay for miners. Once we move the transaction to the lower chain, we can save this part of the cost

Of course, lightning network is not perfect. When using the lightning network, the assets on the main chain should be used as collateral; And this part of assets as collateral can not be used before the user completes the transaction under the chain. This also determines that lightning trading is only suitable for small transactions

the above is the problem of insufficient scalability of Ethereum, as well as the two main solutions: fragmentation technology and lightning network

Second, there are loopholes in Ethereum's smart contract and the infamous Dao event

Ethereum's smart contract is very powerful, but there are loopholes in any code. The biggest controversy of Ethereum's smart contract lies in the so-called loopholes, that is, security issues. According to relevant research, 34200 (about 3%) of the nearly 1 million smart contracts based on Ethereum contain security vulnerabilities, which will allow hackers to steal eth, freeze assets or delete contracts, such as the infamous Dao incident

(1) what does Dao mean

before introcing the Dao event, let's first introce what Dao is. Dao is the abbreviation of decentralized

autonomous organization, which can be understood as decentralized autonomous organization. From the perspective of Ethereum, Dao is a kind of contract or a combination of contracts on the blockchain, which is used to replace the government's review and complex intermediate proceres, so as to achieve an efficient and decentralized trust system. Therefore, Dao is not a specific organization, that is to say, there can be many Dao, all kinds of Dao

(2) the infamous Dao event

however, when we talk about Dao now, we basically refer to the Dao event, that is, the infamous hacker attack event we just mentioned. As we know, the English word "the" refers to "the Dao event". The Dao event

refers to "the Dao event", because we just said that Dao is not a specific organization, there can be many Dao, all kinds of Dao

in 2016, slock.it, a German company focusing on "smart locks", launched the Dao project on Ethereum in order to realize decentralized physical exchange (such as apartments and ships). Since April 30, 2016, the financing window has been open for 28 days

unexpectedly, this Dao project is very popular. It raised more than US $100 million in just half a month. By the end of the whole financing period, it raised a total of US $150 million. Therefore, it has become the largest crowdfunding project in history. However, it didn't last long. In June, hackers took advantage of the loopholes in the smart contract to successfully transfer more than 3.6 million Ethernet coins and put them into a Dao sub organization, which has the same structure as the Dao. At that time, the price of Ethernet currency fell directly from more than $20 to less than $13

this event shows that there are loopholes in smart contracts, and once the loopholes are exploited by hackers, the consequences will be very serious. This is why many people criticize Ethereum and say that its smart contract is not smart

to solve this problem, many foreign companies begin to provide code audit services in order to solve the vulnerability problem of smart contract. From a technical point of view, some teams are currently testing smart contracts. Most of these teams are led by professors from Harvard, Stanford and Yale, and some of them have obtained investment from leading institutions

in addition to the problems of insufficient expansibility and loopholes in smart contracts, the controversy over Ethereum lies in the POS consensus mechanism it pursues, that is, the proof of equity mechanism. Under the proof of equity mechanism, if anyone holds more money and holds it for a longer time, he will get more "rights" (interests) and have the opportunity to get bookkeeping power, Bookkeeping can also be rewarded. In this way, it is easy to create the oligarchic advantage of "the stronger the stronger"

Another problem is the chaos of ICO. ICO is a common way to raise funds for blockchain projects, which we can understand as pre-sale. The outbreak of ICO projects on Ethereum has caused illegal activities such as fund allocation and money fraud under the banner of ICO, which has caused security risks to social and financial stability

3. Ethereum, ETH for short. At the end of 2013, vitalik released the white paper of Ethereum, and in July 2014, the pre-sale of Ethereum began. At that time, insiders called this kind of token issue "crowdfunding". Through the 42 day pre-sale, the Ethereum team raised more than 30000 bitcoins through the pre-sale of 60102216 Ethernet coins; In addition, the early contributors who participated in the development before the pre-sale and the developers who have been engaged in project research for a long time are allocated according to 9.9% of the total amount of Ethernet coins sold at that time. So when Ethereum was officially released, there were more than 72 million Ethereum coins. After the end of Ethereum's pre-sale, it uses the proof of work mechanism POW for mining, and rewards the miners according to 26% of the total amount issued at that time every year. In October 2014, Ethereum reced the block output time from 60 seconds to 12 seconds, and now it is basically stable at 15 seconds, with 5 etheric coins awarded for each block
although the pow mining mechanism is adopted, the block out mechanism of Ethereum is different from that of bitcoin. Due to the short block time of Ethereum, Ethereum is easy to form isolated blocks. Isolated blocks refer to the blocks that are not on the longest chain. Bitcoin's isolated blocks have no block rewards, but in Ethereum, isolated blocks can be referenced. The referenced isolated blocks are called "Uncle blocks", and their packaged data will also be recorded in the blockchain. Unlike bitcoin, Ethereum's TERT block has a reward, and each TERT block can get a reward of 4.375 Ethernet coins at most
Ethereum is a programmable and Turing complete blockchain development platform, which is equivalent to a decentralized global computer. In a programming system, there are usually some virtual machines to compile and execute. Java has JVM. In Ethereum, there is also Ethereum's virtual machine EVM, which can execute any complex algorithm code. Developers can use existing programming languages such as JavaScript or Python to create their own applications on Ethereum. Through Ethereum's virtual machine, you can easily issue digital assets, write smart contracts, set up and run decentralized applications, and set up decentralized autonomous organizations
eth is also known as the internal fuel of Ethereum. Unlike currency digital assets, Ethereum is not only used for transfer, but also for payment of smart contracts
in order to prevent the Ethereum blockchain from being full of junk contracts and junk applications, and to establish and run smart contracts on Ethereum, you must use eth to pay for smart contracts. For example, when you transfer your newly created digital assets on the Ethereum blockchain, you need to use eth to pay the handling fee instead of your newly created digital assets.

4.

Generally, the excellent digital currencies are mostly imported procts, such as bitcoin, Leyte coin, ether coin and so on. However, the domestic Yuanbao coin, Ruitai coin, bitcoin and the tokens of different crowdfunding projects of European crowdfunding are excellent digital currencies

< H2 > development materials

digital currency (English: digital currency) is an alternative currency in the form of electronic currency. At present, no central bank of any government has indicated that it will issue digital currency, and digital currency does not have to have a benchmark currency and a central bank

it is different from the virtual currency in the virtual world, because it can be used for real goods and services transactions, not limited to online games. The early digital currency (digital gold currency) is a form of electronic currency named after the weight of gold. Today's digital currency, such as bitcoin, lightcoin and ppcoin, is an electronic currency created, issued and circulated by check sum cryptography

5. Shenzhen lianpai is a training company in this field.

6. Although it is a new company, its parent company, nebula ocean, is still very powerful in Singapore. It set up interstellar linkage and then deployed IPFs & filecoin together with hellofil, the third largest company in the world. At that time, it still had a certain influence

Nebula ocean is an investment institution established by Singapore consortia in 2013 to focus on blockchain projects. From 2014 to 2018, it has successively participated in the ICO of Ethereum, the Dao, lisk, auger, ant stocks, quantum chain, IPFs and other star projects.

7. Although it is a new company, its parent company, nebula ocean, is still very powerful in Singapore. It set up interstellar linkage and then deployed IPFs & filecoin together with hellofil, the third largest company in the world. At that time, it still had a certain influence. Nebula ocean is a Singapore consortium established in 2013 to focus on blockchain projects. From 2014 to 2018, nebula ocean has successively participated in the ICO of Ethereum, the Dao, lisk, auger, little ant stock, quantum chain, IPFs and other star projects.. If you don't understand, you can ask me directly

8. Ethereum, the world's second largest cryptocurrency, once broke through $3400

Ethereum, the world's second largest cryptocurrency, broke through $3000 for the first time on Monday, and rose further on Tuesday, once breaking through $3400, reaching a new high. Its market value once reached US $395.2 billion, ranking 18th in the global asset market value, surpassing MasterCard and NVIDIA and approaching Wal Mart. Traders attribute the rise of bitcoin to the rise of bitcoin at the end of 2020, and the upgrade of blockchain Ethernet makes bitcoin more useful. So far this year, Ethereum has grown by about 365%

bitcoin network is actually a distributed database, and Ethernet goes a step further. It can be seen as a distributed computer: the blockchain is the ROM of the computer, the contract is the program, and the miner of Ethernet is responsible for the calculation and plays the role of CPU. Of course, this computer is not and can not be used for free, otherwise anyone can store all kinds of junk information and carry out all kinds of trivial calculations

OK, that's what we're going to share in this issue