Ethereum unit M
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
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
under normal circumstances
1G=1000M
1GH=1000MH
1gh=1000mh
to make a real game, let players get a more comfortable experience, and combine with blockchain technology to ensure the interests of players,
in front of the article: the video version is slightly different from the text version. If you want to see my affectionate interpretation, please see the video version (meow understands blockchain phase 22 | sharding: Ethereum is too slow, "disk" him!), The logic of thinking is strange. Please see the extended version
recently, Ethereum has shown an overwhelming positive trend e to the Constantinople upgrade, while Ethereum's upgrade road is like upgrading and fighting monsters, falling into rabbithole. No one knows how deep the hole is. Since it is a long way to go, it is of vital importance to make every step well and accurately. After overcoming this difficulty, Ethereum's next technical difficulty, sharding fragmentation, has been put on the table again. This issue of "meow understands blockchain" will take you into sharding, the magic weapon that makes Ethereum fast
what is sharding
slicing technology is not a new concept. At first, it is an optimization scheme for large central database. Specifically, it divides the data in large database into many shards according to certain rules, and then stores these data in different servers to rece the data access pressure of each server, So as to improve the performance of the whole database system
let's take a small popular example:
for example, meituan, Didi taxi and other software that we often use can be divided according to the "city". Because the data of different cities do not need to communicate, the data of different cities can be stored in different databases, so that the database server can be deployed to the nearest node from the corresponding city, Can also improve the speed of access, why not do it
from the above examples, we should have a preliminary understanding of the concept of fragmentation. What about fragmentation in blockchain scenarios
taking Ethereum fragmentation as an example, in the original single chain system, the overall performance of the public chain depends on the performance of a single node. After fragmentation, each node only needs to undertake the work of the whole network, and each fragmentation works in parallel. According to vitalik, each shard is like a separate galaxy, and each fragmentation is like an independent universe, In this way, the efficiency will be improved naturally! Originally, the total network TPS of Ethereum chain was about 20. Now, if it is increased to 100 pieces, the total network TPS can be increased to 2000. Similarly, the total network capacity will be increased to 100 times of the original
"each node only needs to undertake part of the work of the whole network", which will lead to several major problems. 1. How to determine which piece of work this node is responsible for? 2. Which transactions should be classified into which segments? 3. Does each node only need to store its own transaction information (ledger)
according to the implementation of the above problems, we can divide the fragmentation into three types: network fragmentation, transaction fragmentation and state fragmentation
Network fragmentation: how to divide the nodes of the whole network into different partitions
transaction segmentation: how to divide the whole network transactions into different segments
State fragmentation: how to make each node only maintain the account book in its own fragmentation without affecting the security of the whole system
the difference and connection between main chain and fragmentation chain
we have understood the types of fragmentation, so what's the difference between main chain and shard chain
turn left | turn right
the realization of Ethereum fragmentation is a long process. Even vitalik himself said that it will be graally realized by stages. We'd better look forward to whether fragmentation can move from theory to practice
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
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)
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