Gas Ethereum

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 blockchain has exposed three major problems, and its founder vitalik buterin has been unable to interpret them for a long time. The first is the low performance and TPS of Ethereum blockchain as a whole; The second is that resources are not isolated. The event of cryptokitties virtual cat once occupied 20% of the traffic of the whole Ethereum, which directly caused Ethereum network users unable to carry out timely transactions, which is the biggest pain point of resources not isolated; The third problem lies in the embodiment of Ethereum's governance structure. As a decentralized distributed ledger, the founder team of Ethereum has dominated its network development in the past. The over centralized governance mode has led to the bifurcation of eth, etc and ETF in Ethereum, and the Ethereum community is now in a state of fragmented governance. In the view of Ma Haobo, founder and CEO of "aelf", all kinds of disadvantages of Ethereum are unacceptable. Therefore, the positioning of "aelf" is born for the next generation of decentralized underlying computing platform of Ethereum, which focuses on solving the problems of insufficient performance, non isolation of resources and governance structure of Ethereum.

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. Because blockchain technology has natural advantages in realizing smart contracts. Bitcoin, Ruitai, Laite, Ethereum and other digital cryptocurrencies all use blockchain technology. Blockchain is an important concept of bitcoin. In essence, it is a decentralized database and the underlying technology of bitcoin. Blockchain is a chain of uses

6. Ethereum is a blockchain. Compared with bitcoin, it can increase smart contracts, complete Turing and faster network speed. Etherem has a lot of block chain procts with regional centralization, such as digix, gold Internet of things and so on.

7. Gas & gt; ethestimateGas({ from:ethaccounts [1], to: ethaccounts[2], value:50000000000000 }) 21001 > Ethgasprice 2000000000, as shown above, shows this account [1] = & gt; The transaction of account [2] needs 21001 gas, and the current gasprice is 2000000000. How many gas does it take to send transaction / call contract method in Ethereum

8.

first, smart contracts are so good that they are not useless

smart contracts. As the name suggests, smart contracts refer to contracts that can be executed automatically by computer code; Ethereum virtual machine is used to execute smart contract; Smart account is the carrier that smart contract can be executed. In other words, smart account, this "account" can be controlled by Ethereum virtual machine. According to what control, according to smart contract

there is no free lunch in the world. The smart contract function is so good that it's not useless. When you trade in Ethereum, you have to pay the miner's handling charge. So what's the handling charge you have to pay on Ethereum system, and what's the relationship between

gas and handling charge

2. What's the matter with Ethereum gas

Ethereum gas is similar to automobile fuel. It needs Ethereum gas to drive smart contract. Gas is an English word, Chinese meaning: gas, gasoline, this thing in daily life, is a consumable. Why does Ethereum proce fuel

what is the meaning of gas in Ethereum? In fact, Ethereum's gas is closely related to transaction costs. Ethereum transaction needs service charge. This gas is the calculation mode of service charge of Ethereum

in the setting of Ethereum, the transaction fee is similar to an encrypted fuel, namely gas, which can drive the movement of smart contracts. When Ethereum executes transactions on the blockchain, the fuel will be graally consumed according to the rules of the characteristics

from this point of view, gas is really the same as its original intention, like automobile fuel. If you want to start a car, you must need fuel

What is the difference between the transaction fees of Ethereum gas and bitcoin In essence, Ethereum is a virtual machine, which is decentralized and controlled by people all over the world, forming a "world-class computing network". When you send a token, execute a contract, transfer Ethereum, or do other things on the block, the computer needs to calculate when processing the transaction, which consumes network resources. In this way, you have to pay the "gas" to get the computer to work for you and the miners to process the transaction for you

generally, the higher the gas price the sender is willing to pay, the greater the value the miners get from the transaction, and the more likely the miners are to choose the transaction. In this way, miners are free to choose to trade. In order to set the gas price for the sender as a reference, miners can directly put forward the lowest gas price they need to execute the transaction

How to calculate the gas consumption of Ethereum

when Ethereum virtual machine processes transactions, Virtual Opportunities process one by one according to the operation instructions determined in the transaction, and each operation instruction has a specified gas consumption

Ethereum system stipulates two accounts: one is normal account and the other is smart account

for ordinary transfer transaction, that is to call "normal account", the required gas is fixed 21000

when calling "smart account", because the complexity of smart contract is different, the required gas is also different. The more resources (computation, memory, etc.) used to process transactions, the more gas will be needed. For example, an addition operation will consume 3gas. If more complex operations are performed, the more gas will be consumed

then you may ask a question: when a user's transaction involves a malicious smart contract, the contract is extremely complex, and the execution of the contract will consume unlimited fuel, what should we do? The solution of Ethereum system is: in order to avoid unlimited gas consumption caused by malicious

smart contract, the user needs to set the maximum allowable fuel consumption when sending the transaction, namely

gaslimit. In this way, even if there is a malicious smart contract, the worst case is only within the fuel consumption range specified by gaslimit

What is the relationship between Ethereum gas and transaction fees

on Ethereum, the service charge you pay is equal to gasprice times gasused

you can understand gasprice as the unit price of fuel and gasused as how many liters of fuel the car needs

for a car, if you say 20 yuan per liter of gasoline, 10000 liters of gasoline is 200000 yuan. For Ethereum, each

gas is 20 gigabytes (gigabytes is the unit of quantity of Ethereum currency), and 10000 gas is: 20 times 10000 equals 200000 gigabytes, 20000 gigabytes equals 0.0002 Ethereum, that is to say, the transaction procere is 0.0002 Ethereum

the specific exchange value is shown in the following table:

< p class = "ikqb_ image_ Please click to enter the description of the picture (Note: the basic unit of the quantity of ether coin is "Wei", and the quantity units of ether coin are "Wei", "FeNi" and "Ether", among which "Ether" is used as ordinary transaction“ "Fini" is used as micro trading“ "Saab" and "Wei" are used to carry out contract implementation on cost.) From this we can find that gas is not Ethereum, it is a separate system, its exchange rate and Ethereum into a certain proportion, after the proportion of exchange, the final formation of transaction costs

for specific exchange rate query, you can check the following website:

for details https://jin10086.github.io/etherconVerter/

both gas price and ether price are freely regulated by the market, but they are different in that the price of ether fluctuates according to the market situation, while the price of gas is determined by miners, If the price of fuel falls below the miners' minimum requirements, the miners refuse to process the deal. The separation of gas and Ethereum can protect the system from the possible fluctuation with the rapid change of Ethereum price

generally speaking, most miners will choose to give priority to their interests. When dealing with the transaction, they will arrange according to the gas price from high to low, and give priority to those with high gas price. If you are in a hurry to trade, you need to raise the gas price so that the miners can see you earlier; If you are not in a hurry, you just need to set a gas price, which is above the bottom line of gas price set by miners

How is gas obtained

in fact, gas is the ether coin purchased from the miner. The ether coin in the user's own account can purchase gas from the miner, and the Ethereum client will automatically purchase gas with Ethereum according to the specified maximum transaction expenditure limit

Where did gas go in the end

for each transaction, the initiator of the transaction must set the gas limit and gas price. Different operations will proce different gas costs. When the gas is used up, the miner will stop executing, and the gas used will be used as a reward to the miner. This will involve several situations:

the first situation is that if there is a surplus gas, the miner will stop executing, Then the remaining gas will be returned to the transaction initiator or the creator of the smart contract. For example, if I send an Ethereum to Yiyi, the gas limit I set is 50000, and the gas normally consumed is 21000, then the remaining 29000 that has not been consumed will be returned to me

in the second case, if the gas limit I set is too low, or the Ethereum in my account is not enough to pay for my gas consumption, then the transaction will be cancelled e to insufficient gas, and the gas used for calculation will not be returned to my account

in the third case, if the transaction fails, I have to pay the handling charge for the occupied computing resources

How to set a reasonable gas price

before each transaction, you can query this website to confirm the gas price to be set: https://ethGasstation.info/ To sum up, in this article, we mainly introce the gas and service charge of Ethereum: gas is equivalent to fuel oil. When you process transactions on Ethereum virtual machine, you will consume computing resources, that is, gas. On Ethereum, the service charge you pay is equal to gasprice multiplied by gasused, that is, the unit price of gas multiplied by the total amount of gas consumed. The complexity of the operation is different, and the cost of gas is also different. When the gas is used up, the miner will stop executing, and the gas used will be used as a reward to the miner. The miner will give priority to the trader with higher gas price