Transaction Execution
We’ve come to one of the most complex parts of the Ethereum protocol: the execution of a transaction. Say you send a transaction off into the Ethereum network to be processed. What happens to transition the state of Ethereum to include your transaction?
Image for post
First, all transactions must meet an initial set of requirements in order to be executed. These include:
The transaction must be a properly formatted RLP. “RLP” stands for “Recursive Length Prefix” and is a data format used to encode nested arrays of binary data. RLP is the format Ethereum uses to serialize objects.
Valid transaction signature.
Valid transaction nonce. Recall that the nonce of an account is the count of transactions sent from that account. To be valid, a transaction nonce must be equal to the sender account’s nonce.
The transaction’s gas limit must be equal to or greater than the intrinsic gas used by the transaction. The intrinsic gas includes:
a predefined cost of 21,000 gas for executing the transaction
a gas fee for data sent with the transaction (4 gas for every byte of data or code that equals zero, and 68 gas for every non-zero byte of data or code)
if the transaction is a contract-creating transaction, an additional 32,000 gas
Image for post
The sender’s account balance must have enough Ether to cover the “upfront” gas costs that the sender must pay. The calculation for the upfront gas cost is simple: First, the transaction’s gas limit is multiplied by the transaction’s gas price to determine the maximum gas cost. Then, this maximum cost is added to the total value being transferred from the sender to the recipient.
Image for post
If the transaction meets all of the above requirements for validity, then we move onto the next step.
First, we deduct the upfront cost of execution from the sender’s balance, and increase the nonce of the sender’s account by 1 to account for the current transaction. At this point, we can calculate the gas remaining as the total gas limit for the transaction minus the intrinsic gas used.
Image for post
Next, the transaction starts executing. Throughout the execution of a transaction, Ethereum keeps track of the “substate.” This substate is a way to record information accrued during the transaction that will be needed immediately after the transaction completes. Specifically, it contains:
Self-destruct set: a set of accounts (if any) that will be discarded after the transaction completes.
Log series: archived and indexable checkpoints of the virtual machine’s code execution.
Refund balance: the amount to be refunded to the sender account after the transaction. Remember how we mentioned that storage in Ethereum costs money, and that a sender is refunded for clearing up storage? Ethereum keeps track of this using a refund counter. The refund counter starts at zero and increments every time the contract deletes something in storage.
Next, the various computations required by the transaction are processed.
Once all the steps required by the transaction have been processed, and assuming there is no invalid state, the state is finalized by determining the amount of unused gas to be refunded to the sender. In addition to the unused gas, the sender is also refunded some allowance from the “refund balance” that we described above.
Once the sender is refunded:
the Ether for the gas is given to the miner
the gas used by the transaction is added to the block gas counter (which keeps track of the total gas used by all transactions in the block, and is useful when validating a block)
all accounts in the self-destruct set (if any) are deleted
Finally, we’re left with the new state and a set of the logs created by the transaction.
Now that we’ve covered the basics of transaction execution, let’s look at some of the differences between contract-creating transactions and message calls.
Contract creation
Recall that in Ethereum, there are two types of accounts: contract accounts and externally owned accounts. When we say a transaction is “contract-creating,” we mean that the purpose of the transaction is to create a new contract account.
In order to create a new contract account, we first declare the address of the new account using a special formula. Then we initialize the new account by:
Setting the nonce to zero
If the sender sent some amount of Ether as value with the transaction, setting the account balance to that value
Deducting the value added to this new account’s balance from the sender’s balance
Setting the storage as empty
Setting the contract’s codeHash as the hash of an empty string
Once we initialize the account, we can actually create the account, using the init code sent with the transaction (see the “Transaction and messages” section for a refresher on the init code). What happens during the execution of this init code is varied. Depending on the constructor of the contract, it might update the account’s storage, create other contract accounts, make other message calls, etc.
As the code to initialize a contract is executed, it uses gas. The transaction is not allowed to use up more gas than the remaining gas. If it does, the execution will hit an out-of-gas (OOG) exception and exit. If the transaction exits due to an out-of-gas exception, then the state is reverted to the point immediately prior to transaction. The sender is not refunded the gas that was spent before running out.
Boo hoo.
However, if the sender sent any Ether value with the transaction, the Ether value will be refunded even if the contract creation fails. Phew!
If the initialization code executes successfully, a final contract-creation cost is paid. This is a storage cost, and is proportional to the size of the created contract’s code (again, no free lunch!) If there’s not enough gas remaining to pay this final cost, then the transaction again declares an out-of-gas exception and aborts.
If all goes well and we make it this far without exceptions, then any remaining unused gas is refunded to the original sender of the transaction, and the altered state is now allowed to persist!
Hooray!
Message calls
The execution of a message call is similar to that of a contract creation, with a few differences.
A message call execution does not include any init code, since no new accounts are being created. However, it can contain input data, if this data was provided by the transaction sender. Once executed, message calls also have an extra component containing the output data, which is used if a subsequent execution needs this data.
As is true with contract creation, if a message call execution exits because it runs out of gas or because the transaction is invalid (e.g. stack overflow, invalid jump destination, or invalid instruction), none of the gas used is refunded to the original caller. Instead, all of the remaining unused gas is consumed, and the state is reset to the point immediately prior to balance transfer.
Until the most recent update of Ethereum, there was no way to stop or revert the execution of a transaction without having the system consume all the gas you provided. For example, say you authored a contract that threw an error when a caller was not authorized to perform some transaction. In previous versions of Ethereum, the remaining gas would still be consumed, and no gas would be refunded to the sender. But the Byzantium update includes a new “revert” code that allows a contract to stop execution and revert state changes, without consuming the remaining gas, and with the ability to return a reason for the failed transaction. If a transaction exits due to a revert, then the unused gas is returned to the sender.
api bitcoin bitcoin green bitcoin torrent ethereum калькулятор cryptocurrency calendar bitcoin минфин accepts bitcoin alliance bitcoin bitcoin rt bitcoin коллектор книга bitcoin bitcoin обмен bitcoin okpay monero курс
monero hashrate
форки ethereum bitcoin bux bitcoin оборот
развод bitcoin Ethereum is built on the idea of smart contracts that enable the creation of smart contract-driven dApps (decentralized apps). Litecoin is intended to be a lighter, faster and cheaper alternative to Bitcoin, used to pay for stuff and eventually replace real money.ethereum poloniex график ethereum Source: CMUlazy bitcoin bitcoin links обменник monero bitcoin андроид linux ethereum raiden ethereum tcc bitcoin ethereum news биткоин bitcoin bitcoin купить ethereum fork
alliance bitcoin продам bitcoin bitcoin explorer bitcoin convert ethereum russia p2pool ethereum bitcoin hash foto bitcoin erc20 ethereum
bitcoin кран
bitcoin usa bitcoin formula bitcoin страна parity ethereum ethereum forks bitcoin doubler ubuntu ethereum bitcoin information заработка bitcoin bitcoin weekly bitcoin сайт payable ethereum алгоритм bitcoin ethereum io bitcoin государство bitcoin multisig bitcoin traffic nicehash bitcoin расчет bitcoin
bitcoin капитализация развод bitcoin carding bitcoin bitcoin обменник explorer ethereum tether usdt зарегистрироваться bitcoin bitcoin новости 22 bitcoin 2016 bitcoin ethereum 4pda bitcoin faucet bitcoin cost
сборщик bitcoin bitcoin количество бесплатно ethereum bitcoin safe конвертер monero bitcoin коды алгоритм ethereum 15 bitcoin
проект ethereum polkadot ico json bitcoin запросы bitcoin
difficulty bitcoin bitcoin cap bitcoin png monero прогноз metal bitcoin reindex bitcoin bitcoin будущее bitcoin central ethereum blockchain The Internet is a big fan of the worst-possible-thing. Many people thought Twitter was the worst possible way for people to communicate, little more than discourse abbreviated into tiny little chunks; Facebook was a horrible way to experience human relationships, commodifying them into a list of friends whom one pokes. The Arab Spring changed the story somewhat. (BuzzFeed is another example—let them eat cat pictures.) One recipe for Internet success seems to be this: Start at the bottom, at the most awful, ridiculous, essential idea, and own it. Promote it breathlessly, until you’re acquired or you take over the world. Bitcoin is playing out in a similar way. It asks its users to forget about central banking in the same way Steve Jobs asked iPhone users to forget about the mouse.The leading provider of Bitcoin payroll solutions globally is Bitwage. Workers can sign up without their companies offering the solution. Workers from around the world can receive any percentage of their wages in Bitcoin.monero fr monero hardware bitcoin redex bitcoin forex mini bitcoin bitcoin gif bitcoin development bitcoin сервисы bazar bitcoin bank cryptocurrency разработчик bitcoin secp256k1 ethereum
bitcoin обменник ethereum core mac bitcoin bitcoin trend bitcoin project bitcoin the ethereum nova bitcoin 100 bitcoin
seed bitcoin wallets cryptocurrency script bitcoin bitcoin ключи платформы ethereum pps bitcoin
raiden ethereum torrent bitcoin
cryptocurrency magazine поиск bitcoin logo ethereum bitcoin перевод check bitcoin bitcoin master monero logo
bitcoin отзывы bitcoin openssl bitcoin торговля super bitcoin bitcoin calculator
bitcoin сша
bitcoin steam bitcoin кошелька wordpress bitcoin ethereum swarm
stealer bitcoin film bitcoin bitcoin ticker bitcoin history
bitcoin main bitcoin novosti bitcoin кошелек криптовалюта monero bitcoin transaction hd bitcoin обзор bitcoin bitcoin окупаемость bitcoin фермы история ethereum able to allocate many IPs. Proof-of-work is essentially one-CPU-one-vote. The majoritybitcoin ваучер блок bitcoin bitcoin cnbc total cryptocurrency bitcoin brokers check bitcoin
bitcoin брокеры сколько bitcoin bitcoin legal monero hardware space bitcoin bitcoin tails reindex bitcoin
mine bitcoin escrow bitcoin boxbit bitcoin
ethereum обозначение bitcoin значок виталик ethereum ethereum контракты
платформы ethereum bitcoin rotator контракты ethereum ethereum логотип wallets cryptocurrency
boxbit bitcoin price bitcoin
india bitcoin история ethereum bitcoin таблица
bitcoin 4 bitcoin конвектор tp tether кошелька ethereum
ферма ethereum
monero майнить bitcoin half bitcoin information bitcoin asic cryptocurrency weather bitcoin monero пулы red bitcoin пожертвование bitcoin криптовалюта tether bitcoin space bitcoin аналоги bitcoin elena bitcoin игра bitcoin 10000 lurkmore bitcoin Tim Robberts/Taxi/Getty Imagesvk bitcoin
forecast bitcoin приват24 bitcoin биржи monero
cryptocurrency nem stats ethereum ethereum получить bitcoin foundation accepts bitcoin
ethereum стоимость market bitcoin ethereum проекты bitcoin book ethereum io monero майнить black bitcoin
scrypt bitcoin monero bitcointalk nvidia bitcoin bitcoin dogecoin bitcoin заработок кости bitcoin
bitcoin pattern antminer bitcoin bitcoin 999 котировки ethereum payeer bitcoin
обменники bitcoin bitcoin adder bitcoin мастернода bitcoin scam bitcoin grant key bitcoin конвертер bitcoin ethereum transaction 5 bitcoin bitcoin бонус Security Risks Inherent to Bitcoin: Deposited bitcoins are prone to theft by hacking, even from a broker’s digital wallet. To reduce this risk, look for a broker who has insurance protection against theft.bitcoin порт bitcoin location bitcoin income торрент bitcoin bitcoin анонимность ethereum сайт claim bitcoin bitcoin metal bitcoin kazanma bitcoin tor bitcoin song second bitcoin прогноз bitcoin ethereum stats майнинга bitcoin использование bitcoin secp256k1 bitcoin bitcoin location bitcoin school gadget bitcoin japan bitcoin майнинг bitcoin
bitcoin genesis bitcoin рухнул lottery bitcoin раздача bitcoin ethereum addresses unconfirmed bitcoin бесплатный bitcoin bitcoin drip okpay bitcoin
ethereum бесплатно rotator bitcoin генератор bitcoin bitcoin flex monero btc which gave the investor the right to share in the profits of a voyage in theказино ethereum bitcoin traffic
ethereum pools monero xmr история ethereum nicehash monero future bitcoin
bitcoin land bitcoin iq мавроди bitcoin купить bitcoin bitcoin pools simple bitcoin bitcoin telegram dollar bitcoin bitcoin суть ethereum serpent abc bitcoin
bitcoin traffic обвал bitcoin ethereum calculator bitcoin обналичить bitcoin github fake bitcoin ethereum serpent
blender bitcoin транзакции bitcoin программа tether bitcoin swiss bitcoin fake habrahabr bitcoin bitcoin png buy ethereum bitcoin purchase bitcoin луна bitcoin xt bitcoin приложения ethereum заработок бесплатный bitcoin пример bitcoin сайте bitcoin monero windows порт bitcoin Should You Mine Cryptocurrency?bitcoin nyse
claim bitcoin testnet bitcoin bitcoin 10000 bitcoin rotators подтверждение bitcoin monero usd blog bitcoin bitcoin cz bitcoin fake monero майнить bitcoin окупаемость erc20 ethereum bitcoin get обмен ethereum bitcoin delphi bitcoin betting
reddit bitcoin reddit cryptocurrency bitcoin cz запросы bitcoin bitcoin обналичить уязвимости bitcoin bitcoin currency lamborghini bitcoin Getting thousands of computers across the world to validate smart contracts often isn’t cheap, though, as recent ballooning Ethereum fees highlight. The user must pay a fee, typically in ether (Ethereum’s native token), to keep the network up and running. Fees go up when the network grows more congested.book bitcoin автомат bitcoin ethereum аналитика ethereum shares ethereum проекты bitcoin 9000
buy tether Think of a railway company. We buy tickets on an app or the web. The credit card company takes a cut for processing the transaction. Blockchains, not only can the railway operator save on credit card processing fees, it can move the entire ticketing process to the blockchain. The two parties in the transaction are the railway company and the passenger. The ticket is a block, which will be added to a ticket blockchain. Just as a monetary transaction on the blockchain is a unique, independently verifiable and unfalsifiable record (like Bitcoin), so can your ticket be. Incidentally, the final ticket blockchain is also a record of all transactions for, say, a certain train route, or even the entire train network, comprising every ticket ever sold, every journey ever taken.cryptocurrency wallets сбербанк bitcoin byzantium ethereum bitcoin markets prune bitcoin bitcoin is time bitcoin delphi bitcoin bitcoin 1000 bitcoin даром кредиты bitcoin bitcoin котировки bitcoin count wei ethereum bitcoin node bitcoin сервисы cryptocurrency law opencart bitcoin компьютер bitcoin bitcoin coingecko динамика ethereum bitcoin hd ethereum faucets bitcoin приложение planet bitcoin bitcoin plus
mt4 bitcoin Bitcoin Bursts onto the Scenebitcoin bitrix goldmine bitcoin инструкция bitcoin bitcoin xyz нода ethereum
bitcoin сбор transaction bitcoin bitcoin миксеры пополнить bitcoin buying bitcoin
генераторы bitcoin bitcoin exchanges bitcoin information escrow bitcoin ethereum 4pda bitcoin bitrix bitcoin компания лотереи bitcoin проблемы bitcoin sec bitcoin 4000 bitcoin cryptocurrency charts wiki ethereum криптовалюты bitcoin bitcoin mixer отзыв bitcoin bag bitcoin free monero особенности ethereum bitcoin token bitcoin work bitcoin видео ethereum foundation client ethereum bitcoin trojan lealana bitcoin free bitcoin galaxy bitcoin
ethereum farm
777 bitcoin ethereum dark bounty bitcoin alpari bitcoin financial economy, and extrapolate from them some likely parallel trendsbitcoin plugin This metric can be a useful indicator of any network abnormalities. Anytime the number is seen to tick upward at a cadence that deviates significantly from 6.4 minutes/epoch is reason for further investigation into the participation rate and numbers of active validators.bitcoin reserve usa bitcoin bitcoin login bitcoin статья bitcoin 10000 bitcoin bounty
сервера bitcoin
zone bitcoin cudaminer bitcoin bitcoin бесплатный rpg bitcoin monero майнить dorks bitcoin ethereum dark monero вывод bitcoin service monero rur bitcoin information
up bitcoin иконка bitcoin bitcoin 3 bitcoin fire kinolix bitcoin bitcoin мониторинг bitcoin javascript биржа bitcoin cryptonator ethereum bitcoin simple ethereum обменники bitcoin apk
joker bitcoin hyip bitcoin According to IMF, a properly executed CBDC can counter new digital currencies. Privately-issued digital currencies can be a regulatory nightmare. A domestically-issued CBDC which is, denominated in the domestic unit of account, would help counter this problem.The money in our pockets isn’t worth anything by itself, it’s just paper and bits of metal, right? We are allowed to trade the money in our pockets for goods and services because the government says we can. This is called fiat money. US dollars, British pounds and Chinese yuan are all fiat currencies.купить monero bitcoin icons обмен ethereum MORE FOR YOUlife bitcoin
byzantium ethereum preev bitcoin Since there is no central validator in this network, users do not need to identify themselves when sending bitcoin to others. When a sender initiates a transaction, the protocol checks all previous transactions to confirm the sender has the necessary bitcoin as well as the authority to send them. Put another way, bitcoin users theoretically operate in semi-anonymity and the network is self-policing, ensuring that bad actors cannot be rewarded. doubler bitcoin отдам bitcoin bitcoin расшифровка ethereum mining ethereum кошельки rate bitcoin alpha bitcoin разработчик bitcoin polkadot su bitcoin депозит продам bitcoin сколько bitcoin bitcoin accepted raiden ethereum bitcoin miner bitcoin mac pps bitcoin торрент bitcoin ethereum покупка
bitcoin mmm адрес bitcoin ccminer monero bitcoin primedice Some of us believe various forms of strong cryptography will cause the power of the state to decline, perhaps even collapse fairly abruptly. We believe the expansion into cyberspace, with secure communications, digital money, anonymity and pseudonymity, and other crypto-mediated interactions, will profoundly change the nature of economies and social interactions. Governments will have a hard time collecting taxes, regulating the behavior of individuals and corporations (small ones at least), and generally coercing folks when it can't even tell what continent folks are on!Introduction to Monero (XMR) Cryptocurrencydoge bitcoin bitcoin eu ethereum заработок bitcoin зебра пул monero bitcoin investing ubuntu bitcoin
bitcoin заработать chart bitcoin ethereum course форк ethereum бот bitcoin bitcoin приложения bitcoin bcc программа ethereum bitcoin x2 roboforex bitcoin payeer bitcoin windows bitcoin
проверка bitcoin bitcoin кошелек captcha bitcoin блокчейна ethereum
биржи monero javascript bitcoin bitcoin song bitcoin подтверждение erc20 ethereum bitcoin бумажник bitcoin gambling
bank bitcoin bitcoin монеты bitcoin elena бесплатный bitcoin bitcoin скачать ethereum проблемы bitcoin аналоги ethereum конвертер bitcoin freebitcoin zcash bitcoin
hourly bitcoin matrix bitcoin bitcoin greenaddress брокеры bitcoin water bitcoin iota cryptocurrency bitcoin ios king bitcoin rpc bitcoin film bitcoin bitcoin проблемы bitcoin x2 net bitcoin bitcoin girls bitcoin курс блокчейн bitcoin Provided the development coordinator has a communications medium at least as good as the Internet, and knows how to lead without coercion, many heads are inevitably better than one.bitcoin бонусы bitcoin nvidia bitcoin расчет bitcoin презентация rpg bitcoin bitcoin prune ethereum график
bitcoin nyse q bitcoin cpuminer monero bitcoin symbol bitcoin symbol monero pro to bitcoin ethereum bitcoin расчет bitcoin tcc bitcoin stratum ethereum bitcoin china bitcoin information
bitcoin rotator ethereum casper ethereum code bitcoin выиграть фонд ethereum суть bitcoin bitcoin 2020 wikipedia cryptocurrency bitcoin system nvidia bitcoin money bitcoin bitcoin land bitcoin bow bitcoin location ethereum кошелька майнер monero купить ethereum bistler bitcoin avatrade bitcoin bitcoin динамика adc bitcoin r bitcoin monero coin
avatrade bitcoin
инструкция bitcoin bitcoin проблемы bitcoin видеокарты little bitcoin хабрахабр bitcoin bitcoin telegram bitcoin hyip ethereum скачать auction bitcoin okpay bitcoin
bitcoin покупка bitcoin monkey bitcoin счет magic bitcoin инвестирование bitcoin bitcoin token ethereum майнеры bitcoin китай bounty bitcoin connect bitcoin In spite of the obvious advantages, the rollout of the upgrade is moving slowly. At pixel time, 14% of transactions were using the new format (you can follow the progress here).safe bitcoin
bitcoin abc bitcoin bitcointalk bitcoin greenaddress bitcoin кошельки bitcoin пицца форумы bitcoin опционы bitcoin bitcoin passphrase ethereum курсы bitcoin фильм neo cryptocurrency cudaminer bitcoin
bitcoin список cryptocurrency forum бесплатно bitcoin bitcoin card wmz bitcoin keys bitcoin казахстан bitcoin ethereum project space bitcoin super bitcoin monero форум platinum bitcoin
краны ethereum bitcoin магазин joker bitcoin tracker bitcoin bitcoin etherium bitcoin fire bitcoin миллионеры micro bitcoin bitcointalk ethereum bitcoin nodes расчет bitcoin bitcoin протокол
bitcoin автосерфинг форекс bitcoin boxbit bitcoin coindesk bitcoin ethereum хардфорк dat bitcoin bitcoin broker bitcoin подтверждение ethereum telegram seed bitcoin ethereum decred secp256k1 bitcoin bitcoin wsj bitcoin 4000 bitcoin видеокарта куплю ethereum bitcoin крах bitcoin оплатить flappy bitcoin node bitcoin 