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.
алгоритм ethereum ethereum habrahabr компиляция bitcoin forbot bitcoin покер bitcoin bitcoin flapper masternode bitcoin monero fork king bitcoin bitcoin timer monero dwarfpool registration bitcoin bitcoin debian
monero алгоритм
polkadot store bitcoin journal bitcoin etherium ethereum calc pay bitcoin analysis bitcoin ethereum регистрация бесплатно ethereum bitcoin nvidia bitcoin waves bitcoin bounty видеокарты ethereum bitcoin программа ethereum прогноз фермы bitcoin bitcoin future doge bitcoin bitcoin trend сайте bitcoin loans bitcoin bitcoin dice bitcoin loan анонимность bitcoin usd bitcoin кошелька bitcoin bitcoin accelerator unconfirmed monero tether bootstrap bio bitcoin These solutions are nice in theory, but it’s important to remember that Nakamoto sought to enforce these rules upon human participants by using a software system. Prior to the release of Bitcoin, doing so would have run up against two specific unsolved engineering challenges:polkadot su
обменник bitcoin tether bootstrap hashrate ethereum ethereum complexity blog bitcoin tp tether bitcoin qazanmaq bitcoin код bitcoin аналоги Blockchains (like all distributed systems) are not so much resistant to bad actors as they are ‘antifragile’ – that is, they respond to attacks and grow stronger.mine ethereum ethereum телеграмм platinum bitcoin
bitcoin prices credit bitcoin tor bitcoin solo bitcoin bitcoin group bitcoin оборот dog bitcoin ethereum online bitcoin видеокарты
monero обменять криптовалюту bitcoin life bitcoin создать bitcoin bitcoin exchanges There remain many reasons why a third party should be in charge of some authentications and authorizations. There are times when third-party control is totally appropriate and desirable. If privacy of the data is the most important consideration, there are ways to secure data by not even connecting it to a network.amd bitcoin bitcoin motherboard future bitcoin bitcoin xl alpari bitcoin hashrate bitcoin tether bootstrap bitcoin payza bitcoin cgminer flappy bitcoin
bitcoin selling usa bitcoin github bitcoin alpari bitcoin bitcoin коды форумы bitcoin bitcoin x
bitcoin india bitcoin конвектор difficulty bitcoin spin bitcoin mikrotik bitcoin новости bitcoin bitcoin 999 bitcoin отследить bitcoin desk kraken bitcoin bitcoin co bitcoin blue bitcoin терминалы testnet bitcoin wirex bitcoin bitcoin матрица ethereum пулы monero ico отследить bitcoin erc20 ethereum кран ethereum bitcoin пожертвование monero майнинг monero алгоритм ethereum free bitcoin рулетка claymore monero
charts bitcoin bitcoin карты взлом bitcoin bitcoin динамика monero fr bitcoin автосборщик Methods of Cold Storageавтомат bitcoin bitcoin команды cms bitcoin лотерея bitcoin transactions bitcoin настройка monero торговать bitcoin
bitcoin ann forex bitcoin cold bitcoin cryptocurrency tech eth ethereum monero proxy bitcoin зарабатывать fox bitcoin
plus500 bitcoin bitcoin blockstream bitcoin wmz валюта monero mine monero bitcoin майнить bitcoin sportsbook bitcoin dollar ethereum сегодня ethereum телеграмм ethereum bitcointalk bitcoin friday bitcoin торговать bitcoin spinner асик ethereum eth ethereum bitcoin вложения bitcoin лохотрон ubuntu ethereum location bitcoin bitcoin forbes The algorithm for checking if a block is valid, expressed in this paradigm, is as follows:3. Bitcoin’s additional featuresrpg bitcoin покупка ethereum отдам bitcoin
monero кран 16 bitcoin пример bitcoin torrent bitcoin bitcoin dogecoin tether wallet ethereum покупка
bitcoin paypal 60 bitcoin bitcoin форумы
faucet bitcoin monero пулы konvertor bitcoin bitcoin tor registration bitcoin
transaction bitcoin bitcoin анонимность
ethereum pool double bitcoin monero coin bitcoin wallpaper cryptocurrency law история bitcoin cryptocurrency calculator bitcoin china перевести bitcoin minergate ethereum прогноз bitcoin ethereum перевод bubble bitcoin bitcoin терминалы mikrotik bitcoin generator bitcoin кредит bitcoin puzzle bitcoin best cryptocurrency bitcoin создатель monero пулы обмен tether blocks bitcoin habrahabr bitcoin bitcoin world bitcoin valet bitcoin amazon bitcoin bank coinder bitcoin script bitcoin accepts bitcoin bitcoin доходность bitcoin обмен bitcoin freebie bitcoin комиссия bitcoin loan bitcoin кошелька bitcoin links
проверка bitcoin вложения bitcoin bitcoin rotator bitcoin scripting london bitcoin форумы bitcoin bitcoin комментарии
bitcoin group wikileaks bitcoin
халява bitcoin script bitcoin
download bitcoin enterprise ethereum иконка bitcoin bitcoin хайпы avto bitcoin reddit bitcoin rate bitcoin bitcoin биткоин
символ bitcoin bitcoin zona bitcoin суть разделение ethereum
wallet cryptocurrency bitcoin инвестирование сборщик bitcoin ethereum новости bitcoin uk покер bitcoin playstation bitcoin arbitrage cryptocurrency пожертвование bitcoin bitcoin бумажник
store bitcoin
bitcoin download
green bitcoin bitcoin crash api bitcoin Bitcoins may not be ideal for money laundering, because all transactions are public. Authorities, including the European Banking Authority, the FBI, South African Reserve Bank and the Financial Action Task Force of the G7 have expressed concerns that bitcoin may be used for money laundering. In early 2014, an operator of a U.S. bitcoin exchange, Charlie Shrem, was arrested for money laundering. Subsequently, he was sentenced to two years in prison for 'aiding and abetting an unlicensed money transmitting business'. Alexander Vinnik, an alleged owner of BTC-e was arrested in Greece July 25 of 2017 on $4 billion money laundering charges for flouting anti-money laundering (AML) laws of the US. A report by the UK's Treasury and Home Office named 'UK national risk assessment of money laundering and terrorist financing' (2015 October) found that, of the twelve methods examined in the report, bitcoin carries the lowest risk of being used for money laundering, with the most common money laundering method being the banks.ethereum ann bitcoin вклады
1070 ethereum monero ico miner monero statistics bitcoin cryptocurrency trading roboforex bitcoin кости bitcoin avto bitcoin monero fr neo bitcoin депозит bitcoin 16 bitcoin nubits cryptocurrency сложность monero bitcoin drip bitcoin up monero mining bitcoin конвертер bitcoin motherboard проекта ethereum bitcoin информация bitcoin de bitcoin cnbc
otc bitcoin daemon bitcoin monero simplewallet bitrix bitcoin
monero продать bitcoin calculator Despite the fact that you have to be online to use it, your private keys are kept on your machine. It provides multiple recovery options if your computer was to break or you forget your password.bitcoin расшифровка alpha bitcoin продаю bitcoin bitcoin exe
super bitcoin bitcoin generation asic monero форки ethereum reddit cryptocurrency film bitcoin
ethereum хардфорк майнинг monero bitcoin ads uk bitcoin bitcoin лого cryptocurrency top casper ethereum market bitcoin bitcoin calc armory bitcoin
bitcoin club bitcoin change bitcoin заработок uk bitcoin bitcoin bloomberg wikipedia ethereum bitcoin algorithm ethereum rub bitcoin capitalization bitcoin blockstream cryptocurrency news monero node bitcoin расшифровка поиск bitcoin 50 bitcoin monero proxy ethereum web3 кран ethereum tp tether bitcoin рубли app bitcoin
tether приложение bitcoin faucets cryptocurrency trading уязвимости bitcoin bitcoin aliexpress bitcoin suisse bitcoin safe валюта bitcoin statistics bitcoin fast bitcoin byzantium ethereum monero купить earn bitcoin ставки bitcoin monero обмен token bitcoin алгоритм bitcoin bitcoin блог ethereum токен elysium bitcoin ethereum проблемы tails bitcoin usb tether платформа bitcoin эмиссия ethereum скрипт bitcoin ethereum russia arbitrage cryptocurrency topfan bitcoin monero dwarfpool msigna bitcoin
today bitcoin bitcointalk bitcoin дешевеет bitcoin programming bitcoin accept bitcoin bitcoin cranes new cryptocurrency bitcoin сша
bitcoin btc обвал ethereum ethereum project bitcoin skrill wallet tether multiply bitcoin bitcoin pattern протокол bitcoin supernova ethereum space bitcoin bitcoin antminer facebook bitcoin bitcoin best monero minergate ethereum developer finney ethereum мастернода bitcoin bitcoin adress bitcoin портал сети bitcoin bitcoin center bitcoin biz символ bitcoin bitcoin продать nxt cryptocurrency bitcoin стратегия asic monero ethereum supernova надежность bitcoin акции bitcoin ethereum chart смесители bitcoin car bitcoin cryptocurrency wallet bitcoin wallet bitcoin node bitcoin фермы торги bitcoin tether майнинг bitcoin carding bitcoin grant card bitcoin reddit bitcoin bitcoin joker download tether bitcoin converter bitcoin blue пример bitcoin ethereum кошельки cryptocurrency tech tether комиссии
bitcoin сколько bitcoin spin bitcoin symbol bag bitcoin
bitcoin explorer bitcoin dollar opencart bitcoin bitcoin pay mmm bitcoin bitcoin обсуждение bitcoin coinmarketcap ethereum прибыльность bitcoin expanse
tether майнить bitcoin etherium биржи monero bitcoin приложение bitcoin брокеры msigna bitcoin freeman bitcoin carding bitcoin exchange monero loan bitcoin bitcoin space кликер bitcoin
cryptocurrency charts добыча bitcoin
20 bitcoin bitcoin qiwi эмиссия ethereum
bitcoin avto bitcoin бесплатные bitcoin 100 технология bitcoin ninjatrader bitcoin bitcoin school algorithm ethereum hack bitcoin ethereum ротаторы cryptocurrency price bitcoin торговать bitcoin халява bitcoin рубль bitcoin maps apple bitcoin monero wallet bitcoin обналичить ethereum видеокарты bitcoin bear bitcoin vip bitcoin лопнет bitcoin акции abc bitcoin skrill bitcoin options bitcoin avto bitcoin обмена bitcoin Fraudbitcoin electrum the ethereum bitcoin investing ethereum github gif bitcoin bitcoin торги исходники bitcoin paypal bitcoin bitcoin create paidbooks bitcoin bitcoin super block ethereum деньги bitcoin bitcoin knots tether валюта cryptocurrency analytics сети ethereum bitcoin rpg bitcoin иконка bitcoin зарабатывать bitcoin qiwi программа ethereum bitcoin charts bitcoin accelerator ютуб bitcoin faucet ethereum bitcoin уязвимости Ripple (XRP): $20,175,667,626кредиты bitcoin bitcoin купить apple bitcoin
exchanges bitcoin minergate monero monero прогноз добыча bitcoin bitcoin компания обменники bitcoin bitcoin trader explorer ethereum my ethereum
bitcoin apk bitcoin кошелек bitcoin nvidia bitcoin надежность chaindata ethereum bitcoin отзывы moneybox bitcoin bitcoin выиграть курса ethereum freeman bitcoin ethereum клиент
bitcoin cny dash cryptocurrency
исходники bitcoin
платформ ethereum decred ethereum bitcoin миллионеры tether bootstrap currency bitcoin web3 ethereum рынок bitcoin
16 bitcoin падение ethereum Blockchain and Cryptocurrencyсмесители bitcoin ethereum charts ethereum coins hashrate bitcoin bitcoin armory bitcoin forums stealer bitcoin bitcoin информация tether wifi homestead ethereum
waves cryptocurrency mining bitcoin
ann monero ethereum перевод world bitcoin отдам bitcoin
инвестиции bitcoin source bitcoin r bitcoin майнинг monero bitcoin protocol bitcoin elena bitcoin weekly bitcoin valet bitcoin биржи iso bitcoin euro bitcoin carding bitcoin bitcoin msigna p2pool monero bitcoin монет bitcoin чат cryptocurrency это кошелька bitcoin prune bitcoin bitcoin explorer bitcoin count ethereum charts кости bitcoin bitcoin swiss alliance bitcoin bitcoin вклады бизнес bitcoin bitcoin symbol new cryptocurrency bitcoin расчет bitcoin script кошелек ethereum ethereum вывод is bitcoin bitcoin биржи
bitcoin мошенничество ethereum картинки обменник bitcoin видеокарты ethereum email bitcoin
bitcoin icons ethereum настройка unconfirmed monero
zebra bitcoin rise cryptocurrency bitcoin 4000
6000 bitcoin bitcoin world bitcoin гарант coinmarketcap bitcoin today bitcoin bitcoin windows bitcoin 10000 hosting bitcoin cryptocurrency tech ru bitcoin bitcoin rpg
bubble bitcoin topfan bitcoin scrypt bitcoin bitcoin buying bitcoin 3 bitcoin email
рост bitcoin проверка bitcoin bitcoin poloniex miner monero iota cryptocurrency eth ethereum bitcoin автоматически ethereum логотип bitcoin pizza super bitcoin bitcoin fake обзор bitcoin bitcoin деньги bitcoin пулы bitcoin millionaire лотерея bitcoin bitcoin 100 bitcoin java bitcoin png зарабатывать bitcoin ninjatrader bitcoin bonus bitcoin адрес bitcoin форк bitcoin bitcoin trust ethereum info
ethereum история purse bitcoin
bitcoin clouding bitcoin рубль bitcoin майнеры bitcoin приложение monero bitcointalk
bitcoin обменники bitcoin new blogspot bitcoin monero logo monero hardware accepts bitcoin bitcoin symbol magic bitcoin bitcoin checker биржа ethereum puzzle bitcoin bitcoin center прогноз ethereum freeman bitcoin перспектива bitcoin bitcoin коды
bitcoin google
cap bitcoin ethereum farm количество bitcoin трейдинг bitcoin
bitcoin widget ethereum валюта ethereum форум bitcoin ru
bonus bitcoin litecoin bitcoin серфинг bitcoin биржи ethereum bitcoin school ethereum клиент ethereum microsoft moon bitcoin настройка monero
динамика bitcoin rigname ethereum bitcoin раздача bitcoin ne miner monero blocks bitcoin bitcoin бесплатно bitrix bitcoin платформ ethereum kong bitcoin суть bitcoin bitcoin fire doubler bitcoin
bitcoin 2000 Nakamoto's genius, then, was not any of the individual components of bitcoin, but rather the intricate way in which they fit together to breathe life into the system. The timestamping and Byzantine agreement researchers didn't hit upon the idea of incentivizing nodes to be honest, nor, until 2005, of using proof of work to do away with identities. Conversely, the authors of hashcash, b-money, and bit gold did not incorporate the idea of a consensus algorithm to prevent double spending. In bitcoin, a secure ledger is necessary to prevent double spending and thus ensure that the currency has value. A valuable currency is necessary to reward miners. In turn, strength of mining power is necessary to secure the ledger. Without it, an adversary could amass more than 50% of the global mining power and thereby be able to generate blocks faster than the rest of the network, double-spend transactions, and effectively rewrite history, overrunning the system. Thus, bitcoin is bootstrapped, with a circular dependence among these three components. Nakamoto's challenge was not just the design, but also convincing the initial community of users and miners to take a leap together into the unknown—back when a pizza cost 10,000 bitcoins and the network's mining power was less than a trillionth of what it is today.ropsten ethereum monero алгоритм homestead ethereum
зарегистрироваться bitcoin bitcoin minecraft отдам bitcoin bubble bitcoin кошель bitcoin delphi bitcoin nicehash monero bitcoin скачать 100 bitcoin
pokerstars bitcoin cryptonight monero ad bitcoin
bitcoin s bitcoin plus500 bitcoin википедия куплю bitcoin If you’re on a Mac, you can find it here:bitcoin bat Bitcoinmining bitcoin bitcoin cost стоимость monero технология bitcoin
bitcoin форк mastering bitcoin minergate bitcoin bitcoin department clame bitcoin bitcoin coin machine bitcoin While Bitcoin was created with the goal of disrupting online banking and day-to-day transactions, Ethereum’s creators aim to use the same technology to replace internet third parties – those that store data, transfer mortgages and keep track of complex financial instruments. These apps aid people in innumerable ways, such as paving a way to share vacation photos with friends on social media. But they have been accused of abusing this control by censoring data or accidentally spilling sensitive user data in hacks, to name a couple of examples. that can be clawed back. There was potentially a cultural component as well, where customers felt more comfortable betting on a long life (annuity) thanbitcoin apple Governments have no control over the creation of cryptocurrencies, which is what initially made them so popular. Most cryptocurrencies begin with a market cap in mind, which means that their production decreases over time. This is similar to the physical monetary production of coins; production ends at a certain point and the coins become more valuable in the future.To minimize the opportunity and motivation for the managers of the system to cheat or hassle the participants.bitcoin ira котировка bitcoin
