Function of Ethereum accountonce
Publish: 2021-04-24 15:36:45
1. A virtual currency with a wallet doesn't mean it's more professional and advanced. The existence of digital currency wallet is the premise of currency existence. Currency without wallet can be identified as fraud
mainstream digital currencies such as bitcoin, Puyin, Laite, Ethereum and dogcoin all exist in wallets, and wallets existed before the release of such currencies.
mainstream digital currencies such as bitcoin, Puyin, Laite, Ethereum and dogcoin all exist in wallets, and wallets existed before the release of such currencies.
2. At the top of Ethereum is DAPP. It exchanges with the smart contract layer through Web3. JS. All smart contracts run on EVM (Ethereum virtual machine) and use RPC calls. Below EVM and RPC are the four core contents of Ethereum, including: blockchain, consensus algorithm, mining and network layer. Except DAPP, all other parts are in the Ethereum client. The most popular Ethereum client is geth (go Ethereum)
3.
Blockchain is a term in the field of information technology. In essence, it is a shared database. The data or information stored in it is characterized by "unforgeability", "trace in the whole process", "traceability", "openness and transparency" and "collective maintenance". Based on these characteristics, blockchain technology has laid a solid "trust" foundation, created a reliable "cooperation" mechanism, and has broad application prospects
on January 10, 2019, the state Internet Information Office issued the regulations on the management of blockchain information services. In October 24, 2019, ring the eighteenth collective learning of the Central Political Bureau, general secretary Xi Jinping stressed that "block chain as an important breakthrough in core technology and independent innovation", "accelerating the development of block chain technology and instrial innovation". "Blockchain" has entered the public field of vision and become the focus of social attention
on December 2, 2019, the word was selected into the top ten catchwords of "biting words" in 2019
extended data:
Application of blockchain Finance:
since 2016, the major financial giants have also carried out blockchain innovation projects to explore the possibility of applying blockchain Technology in various financial scenarios. In particular, Puyin group took the lead in creating a "blockchain +" standard digital currency
standard digital currency refers to the process of assets identification, evaluation, right confirmation and insurance completed by a third party organization, which is written into the blockchain through careful digital algorithm to form the standard corresponding relationship between assets and digital currency, which is called standard digital currency
in order to realize the great leap forward development of blockchain finance, promote the new development of China's economy, accelerate the circulation of global assets, and realize the dream of rejuvenation that has been struggling for generations, Puyin group will hold the Guiyang strategic development ceremony of Puyin blockchain finance in Guizhou on December 9, 2016
the meeting will discuss the realization of digital circulation of assets by blockchain, the financial transaction mode of blockchain, and the application of blockchain services and social public instry. This conference will mark the beginning of the application of blockchain finance and the change and development of the new financial ecology
4. The token of Ethereum is proced in the process of mining, with a mining rate of 5 Ethereum coins per piece. The mining process of Ethereum is almost the same as that of bitcoin. For each transaction, miners can use the computer to run the unique title metadata of the block through hash function, and guess the answer repeatedly and quickly until one of them wins
many new users believe that the sole purpose of mining is to generate ether in a way that does not require a central issuer (see our guide "what is ether?"). It's true. The token of Ethereum is proced in the process of mining, with a mining rate of 5 Ethereum coins per piece. But mining is at least as important. Usually, banks are responsible for keeping accurate records of transactions. They make sure that money is not created out of thin air and that users don't cheat and spend money many times. However, blockchain introces a new way to keep records, the whole network instead of intermediary, to verify transactions and add them to the public ledger
Ethereum mining
although "no trust" or "trust minimization" monetary system is the goal, there are still people who need to ensure the security of financial records and ensure that no one cheats. Mining is one of the innovations that makes decentralized records possible. Miners have reached a consensus on the history of transactions in terms of preventing fraud (especially double spending on ether) - an interesting issue that hasn't been addressed before the decentralized currency works on the blockchain. While Ethereum is looking at other ways to reach a consensus on the effectiveness of the deal, mining currently keeps the platform together
how mining works
today, the mining process of Ethereum is almost the same as that of bitcoin. For each transaction, the miner can use the computer to guess the answer repeatedly and quickly until one of them wins. More specifically, the miner will run the unique header metadata (including time stamp and software version) of the block through the hash function (which will return a fixed length, unordered string of numbers and letters, which appears to be random), changing only the 'nonce value', which will affect the hash value of the result
if the miner finds a hash that matches the current target, the miner will be granted ether and broadcast the block across the network for each node to verify and add to their own ledger . If miner B finds the hash, miner a stops working on the current block and repeats the process for the next block. It's hard for miners to cheat in this game. There is no way to fake the work and come up with the right answer to the puzzle. That's why solving puzzles is called "proof of work."
on the other hand, others have little time to verify whether the hash value is correct, which is exactly what each node does. About every 12-15 seconds, a miner finds a stone. If the miner starts to solve the puzzle faster or slower than this, the algorithm will automatically re adjust the difficulty of the problem so that the miner can rebound to about 12 seconds of solution time
miners earn these ethers randomly, and their profitability depends on their luck and the computing power they put in. The specific workload verification algorithm used by Ethereum is called "ethash", which aims to require more memory, making it difficult to mine with expensive ASIC. Special mining chips are now the only profitable way to mine bitcoin
in a sense, ethash may have achieved this goal successfully, because dedicated ASIC is not available for Ethereum (at least not yet). In addition, as Ethereum aims to shift from proof of work mining to "proof of equity" (which we will discuss below), buying ASIC may not be a wise choice because it may not prove useful for a long time< However, Ethereum may never need miners. Developers plan to abandon proof of work, the algorithm currently used by the network to determine which transactions are valid and protect them from tampering to support proof of equity, which is guaranteed by token owners. If and when the algorithm is launched, proof of equity can become a means to achieve distributed consensus, and the consensus uses less resources.
many new users believe that the sole purpose of mining is to generate ether in a way that does not require a central issuer (see our guide "what is ether?"). It's true. The token of Ethereum is proced in the process of mining, with a mining rate of 5 Ethereum coins per piece. But mining is at least as important. Usually, banks are responsible for keeping accurate records of transactions. They make sure that money is not created out of thin air and that users don't cheat and spend money many times. However, blockchain introces a new way to keep records, the whole network instead of intermediary, to verify transactions and add them to the public ledger
Ethereum mining
although "no trust" or "trust minimization" monetary system is the goal, there are still people who need to ensure the security of financial records and ensure that no one cheats. Mining is one of the innovations that makes decentralized records possible. Miners have reached a consensus on the history of transactions in terms of preventing fraud (especially double spending on ether) - an interesting issue that hasn't been addressed before the decentralized currency works on the blockchain. While Ethereum is looking at other ways to reach a consensus on the effectiveness of the deal, mining currently keeps the platform together
how mining works
today, the mining process of Ethereum is almost the same as that of bitcoin. For each transaction, the miner can use the computer to guess the answer repeatedly and quickly until one of them wins. More specifically, the miner will run the unique header metadata (including time stamp and software version) of the block through the hash function (which will return a fixed length, unordered string of numbers and letters, which appears to be random), changing only the 'nonce value', which will affect the hash value of the result
if the miner finds a hash that matches the current target, the miner will be granted ether and broadcast the block across the network for each node to verify and add to their own ledger . If miner B finds the hash, miner a stops working on the current block and repeats the process for the next block. It's hard for miners to cheat in this game. There is no way to fake the work and come up with the right answer to the puzzle. That's why solving puzzles is called "proof of work."
on the other hand, others have little time to verify whether the hash value is correct, which is exactly what each node does. About every 12-15 seconds, a miner finds a stone. If the miner starts to solve the puzzle faster or slower than this, the algorithm will automatically re adjust the difficulty of the problem so that the miner can rebound to about 12 seconds of solution time
miners earn these ethers randomly, and their profitability depends on their luck and the computing power they put in. The specific workload verification algorithm used by Ethereum is called "ethash", which aims to require more memory, making it difficult to mine with expensive ASIC. Special mining chips are now the only profitable way to mine bitcoin
in a sense, ethash may have achieved this goal successfully, because dedicated ASIC is not available for Ethereum (at least not yet). In addition, as Ethereum aims to shift from proof of work mining to "proof of equity" (which we will discuss below), buying ASIC may not be a wise choice because it may not prove useful for a long time< However, Ethereum may never need miners. Developers plan to abandon proof of work, the algorithm currently used by the network to determine which transactions are valid and protect them from tampering to support proof of equity, which is guaranteed by token owners. If and when the algorithm is launched, proof of equity can become a means to achieve distributed consensus, and the consensus uses less resources.
5. 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
6. To create a Genesis configuration file:
first, you need to create a "Genesis" JSON configuration file, which describes some parameters of the genesis block. The following is the content of the file:
{
& quot; coinbase": & quot;& quot;,< br />" config": {< br />" homesteadBlock": 5
},
" difficulty": & quot; 0x20000",< br />" extraData": & quot; 0x",< br />" gasLimit": & quot; 0x2FEFD8",< br />" mixhash": & quot;& quot;,< br />" nonce": & quot; 0x0",< br />" parentHash": & quot; 000000000000000000000000",< br />" timestamp": & quot; 0x00",< br />" alloc": {< br />"& quot;:< br />{
" balance":& quot;& quot;
}
}
} 1234567891011213141516171819
the above code into a text file and name it genesis.json
Genesis!:
in order not to conflict with the data of the main chain, it is recommended to establish your own private chain data folder. On my computer, I built an ethdbspace as the Ethereum experimental work area on disk e, and created a privchain folder as the data storage folder of my first private chain
here, in order to facilitate management, I put genesis.json under the ethdbspace folder
open the windows command line
type the following command
geth -- dataDir & quot; E:\ EthDBSpace\ PrivChain" init " E:\ EthDBSpace\ genesis.json" 1
– the dataDir option is used to specify the data directory of our private chain. On my computer, it's E: &; EthDBSpace\ Privchain
init is the genesis command, followed by our Genesis configuration file path
after clicking enter, the execution result is as follows
at this time, genesis is complete
create an account:
in order to do experiments on the private chain, we also need to create our own account on the private chain
windows command line, type
geth -- dataDir & quot; E:\ EthDBSpace\ PrivChain" Console1
we have successfully created the world, so when we enter the client for the second time, we do not need to specify the genesis.json file path again, but directly – dataDir to indicate the private link data path
the console command is used to open the command line of geth
after clicking enter, the client will be initialized for a while. After the command prompt appears, it means that you have entered the geth console
type
personal. Newaccount (& #) in the geth command line; Your Password') 1
the personal.newaccount function is used to create an account, in which the parameter is the account password.
after clicking enter, the account creation address will be listed in green below the command, that is, the public key of the account.
we can check the account balance first, In the geth command line, type:
My = eth. Accounts [0]
eth. Getbalance (my) 12
My = eth. Accounts [0]. The purpose of this sentence is to assign the account address we just created to my variable. This can simplify the subsequent account address input. Among them, eth.accounts records the addresses of all accounts on this machine. Since we created an account for the first time, there is only one account on the computer at present. So here we use eth. Accounts [0] to extract the first account address. The eth.getbalance function is used to obtain the account balance, and the parameters are filled in the account address. The my variable here records the address of the first account
I hope my answer can help you
first, you need to create a "Genesis" JSON configuration file, which describes some parameters of the genesis block. The following is the content of the file:
{
& quot; coinbase": & quot;& quot;,< br />" config": {< br />" homesteadBlock": 5
},
" difficulty": & quot; 0x20000",< br />" extraData": & quot; 0x",< br />" gasLimit": & quot; 0x2FEFD8",< br />" mixhash": & quot;& quot;,< br />" nonce": & quot; 0x0",< br />" parentHash": & quot; 000000000000000000000000",< br />" timestamp": & quot; 0x00",< br />" alloc": {< br />"& quot;:< br />{
" balance":& quot;& quot;
}
}
} 1234567891011213141516171819
the above code into a text file and name it genesis.json
Genesis!:
in order not to conflict with the data of the main chain, it is recommended to establish your own private chain data folder. On my computer, I built an ethdbspace as the Ethereum experimental work area on disk e, and created a privchain folder as the data storage folder of my first private chain
here, in order to facilitate management, I put genesis.json under the ethdbspace folder
open the windows command line
type the following command
geth -- dataDir & quot; E:\ EthDBSpace\ PrivChain" init " E:\ EthDBSpace\ genesis.json" 1
– the dataDir option is used to specify the data directory of our private chain. On my computer, it's E: &; EthDBSpace\ Privchain
init is the genesis command, followed by our Genesis configuration file path
after clicking enter, the execution result is as follows
at this time, genesis is complete
create an account:
in order to do experiments on the private chain, we also need to create our own account on the private chain
windows command line, type
geth -- dataDir & quot; E:\ EthDBSpace\ PrivChain" Console1
we have successfully created the world, so when we enter the client for the second time, we do not need to specify the genesis.json file path again, but directly – dataDir to indicate the private link data path
the console command is used to open the command line of geth
after clicking enter, the client will be initialized for a while. After the command prompt appears, it means that you have entered the geth console
type
personal. Newaccount (& #) in the geth command line; Your Password') 1
the personal.newaccount function is used to create an account, in which the parameter is the account password.
after clicking enter, the account creation address will be listed in green below the command, that is, the public key of the account.
we can check the account balance first, In the geth command line, type:
My = eth. Accounts [0]
eth. Getbalance (my) 12
My = eth. Accounts [0]. The purpose of this sentence is to assign the account address we just created to my variable. This can simplify the subsequent account address input. Among them, eth.accounts records the addresses of all accounts on this machine. Since we created an account for the first time, there is only one account on the computer at present. So here we use eth. Accounts [0] to extract the first account address. The eth.getbalance function is used to obtain the account balance, and the parameters are filled in the account address. The my variable here records the address of the first account
I hope my answer can help you
7. Ethernet is a kind of digital token of Ethereum, which is regarded as "bitcoin version 2.0". It uses the blockchain technology "Ethereum", which is different from bitcoin. Developers need to pay for Ethernet to support the operation of the application. Like other digital currencies, master Cai suggested that ether currency can be bought and sold on the trading platform< However, trading has been banned in China and it is suggested to invest in other digital currencies.
8. Return the result of ifconfig
eth0 to awk for processing
where - F & # 39;:|< br />+'
this is a separator defined by awk and then matched with "BCAST & quot;, Take the content of the fourth column
since your command is not universal, you can't output the result here, but you should intercept the broadcast address
eth0 to awk for processing
where - F & # 39;:|< br />+'
this is a separator defined by awk and then matched with "BCAST & quot;, Take the content of the fourth column
since your command is not universal, you can't output the result here, but you should intercept the broadcast address
9. Liuhe District is the north gate of Nanjing City, adjacent to Tianchang City in Anhui Province in the north, Yangzhou City in Jiangsu Province in the East, and the "golden waterway" of the Yangtze River in the south. It belongs to the "Golden Triangle" Economic Zone in the lower reaches of the Yangtze River. It is the hometown of Nanjing Yuhuashi, a "national treasure given by heaven and a unique Chinese nation", and the birthplace of Chinese folk song "Jasmine". Liuhe, an ancient civilization, appeared in history more than 2000 years ago. It has a long history, prosperous economy and simple folk customs
in May 2002, with the approval of the State Council, the former Liuhe County and the former factory area merged to form a new Liuhe District, which governs five streets, 14 towns and a provincial Economic Development Zone, with a population of 870000 and a land area of 1500 square kilometers, one sixth and one fourth of that of Nanjing respectively. Liuhe is not only an ancient city with a long history, but also a new district full of vitality
Liuhe has unique geographical advantages and convenient transportation. Ninghu, Ningtong and Ninglian expressways, Jiangbei Avenue, Jinjiang highway, Nanjing Yangtze River Bridge and the second bridge, as well as Ninghuai expressway, ningbeng Expressway and riverside Expressway under construction are crisscross in the area, extending in all directions; With the construction of the fourth Yangtze River Bridge, Liuhe airport, Jiangbei viact and other national and provincial key projects, and the relocation of the North toll station of the Yangtze River Bridge, Liuhe has been integrated into the main city of Nanjing; Liuhe is only an hour's drive away from Chuzhou, Tianchang, Yangzhou and Lukou International airports, and about two hours to Shanghai, which is in the one hour metropolitan area of East China; The west to east gas transmission project crosses 35 km from east to West in the area, with two off load stations; Along the Yangtze River, there are 45 kilometers of deep water coastline, which can be used to build two 10000 ton deep-water docks; Chuhe River runs through the whole territory and is navigable in all seasons
Liuhe region has a strong instrial foundation and obvious characteristic advantages. Yangzi Petrochemical, Nanjing Iron and Steel Group, Yangzi BASF company and other national super large enterprises are concentrated along the river, with advantages in chemical, steel and other raw materials supply and market sales; As a national heavy chemical instry base, Nanjing Chemical Instrial Park is an important part of Jiangsu's strategy of developing along the Yangtze River. The central urban area integrates politics, economy and culture. It is densely populated, prosperous in commerce and trade, and has a superior living environment. The northern region is the main procing area of pollution-free vegetables, economic fruits and other high-quality agricultural procts; The National Geopark, AA Jinniu Lake scenic spot and Pingshan provincial forest park have superior ecological environment. The air quality monitoring control area of Jiangsu Province is located in Zhuzhen forest park
most of the landforms in the region belong to Ningzhenyang mountainous area, with high terrain in the north and low terrain in the south. The northern part is hilly area, the central part is valley plain and hilly area, and the southern part is plain and polder area along the river. Subtropical humid climate, long frost free period, more precipitation, sufficient sunshine, four distinct seasons
there are 72400.8 hectares of cultivated land, accounting for 49.3% of the total area of the region; The garden area is 1657 hectares, accounting for 1.1%; The forest land is 92504 hectares, accounting for 6.3%; 2 ha, accounting for 0. 5%; 3 hectares, accounting for 1.9%; 6 hectares, accounting for 15. 3%; The water area is 31913.6 hectares, accounting for 21.8%; 5 hectares of unused land, accounting for 3.8%.
in May 2002, with the approval of the State Council, the former Liuhe County and the former factory area merged to form a new Liuhe District, which governs five streets, 14 towns and a provincial Economic Development Zone, with a population of 870000 and a land area of 1500 square kilometers, one sixth and one fourth of that of Nanjing respectively. Liuhe is not only an ancient city with a long history, but also a new district full of vitality
Liuhe has unique geographical advantages and convenient transportation. Ninghu, Ningtong and Ninglian expressways, Jiangbei Avenue, Jinjiang highway, Nanjing Yangtze River Bridge and the second bridge, as well as Ninghuai expressway, ningbeng Expressway and riverside Expressway under construction are crisscross in the area, extending in all directions; With the construction of the fourth Yangtze River Bridge, Liuhe airport, Jiangbei viact and other national and provincial key projects, and the relocation of the North toll station of the Yangtze River Bridge, Liuhe has been integrated into the main city of Nanjing; Liuhe is only an hour's drive away from Chuzhou, Tianchang, Yangzhou and Lukou International airports, and about two hours to Shanghai, which is in the one hour metropolitan area of East China; The west to east gas transmission project crosses 35 km from east to West in the area, with two off load stations; Along the Yangtze River, there are 45 kilometers of deep water coastline, which can be used to build two 10000 ton deep-water docks; Chuhe River runs through the whole territory and is navigable in all seasons
Liuhe region has a strong instrial foundation and obvious characteristic advantages. Yangzi Petrochemical, Nanjing Iron and Steel Group, Yangzi BASF company and other national super large enterprises are concentrated along the river, with advantages in chemical, steel and other raw materials supply and market sales; As a national heavy chemical instry base, Nanjing Chemical Instrial Park is an important part of Jiangsu's strategy of developing along the Yangtze River. The central urban area integrates politics, economy and culture. It is densely populated, prosperous in commerce and trade, and has a superior living environment. The northern region is the main procing area of pollution-free vegetables, economic fruits and other high-quality agricultural procts; The National Geopark, AA Jinniu Lake scenic spot and Pingshan provincial forest park have superior ecological environment. The air quality monitoring control area of Jiangsu Province is located in Zhuzhen forest park
most of the landforms in the region belong to Ningzhenyang mountainous area, with high terrain in the north and low terrain in the south. The northern part is hilly area, the central part is valley plain and hilly area, and the southern part is plain and polder area along the river. Subtropical humid climate, long frost free period, more precipitation, sufficient sunshine, four distinct seasons
there are 72400.8 hectares of cultivated land, accounting for 49.3% of the total area of the region; The garden area is 1657 hectares, accounting for 1.1%; The forest land is 92504 hectares, accounting for 6.3%; 2 ha, accounting for 0. 5%; 3 hectares, accounting for 1.9%; 6 hectares, accounting for 15. 3%; The water area is 31913.6 hectares, accounting for 21.8%; 5 hectares of unused land, accounting for 3.8%.
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