Transaction and messages
We noted earlier that Ethereum is a transaction-based state machine. In other words, transactions occurring between different accounts are what move the global state of Ethereum from one state to the next.
In the most basic sense, a transaction is a cryptographically signed piece of instruction that is generated by an externally owned account, serialized, and then submitted to the blockchain.
There are two types of transactions: message calls and contract creations (i.e. transactions that create new Ethereum contracts).
All transactions contain the following components, regardless of their type:
nonce: a count of the number of transactions sent by the sender.
gasPrice: the number of Wei that the sender is willing to pay per unit of gas required to execute the transaction.
gasLimit: the maximum amount of gas that the sender is willing to pay for executing this transaction. This amount is set and paid upfront, before any computation is done.
to: the address of the recipient. In a contract-creating transaction, the contract account address does not yet exist, and so an empty value is used.
value: the amount of Wei to be transferred from the sender to the recipient. In a contract-creating transaction, this value serves as the starting balance within the newly created contract account.
v, r, s: used to generate the signature that identifies the sender of the transaction.
init (only exists for contract-creating transactions): An EVM code fragment that is used to initialize the new contract account. init is run only once, and then is discarded. When init is first run, it returns the body of the account code, which is the piece of code that is permanently associated with the contract account.
data (optional field that only exists for message calls): the input data (i.e. parameters) of the message call. For example, if a smart contract serves as a domain registration service, a call to that contract might expect input fields such as the domain and IP address.
Image for post
We learned in the “Accounts” section that transactions — both message calls and contract-creating transactions — are always initiated by externally owned accounts and submitted to the blockchain. Another way to think about it is that transactions are what bridge the external world to the internal state of Ethereum.
Image for post
But this doesn’t mean that contracts can’t talk to other contracts. Contracts that exist within the global scope of Ethereum’s state can talk to other contracts within that same scope. The way they do this is via “messages” or “internal transactions” to other contracts. We can think of messages or internal transactions as being similar to transactions, with the major difference that they are NOT generated by externally owned accounts. Instead, they are generated by contracts. They are virtual objects that, unlike transactions, are not serialized and only exist in the Ethereum execution environment.
When one contract sends an internal transaction to another contract, the associated code that exists on the recipient contract account is executed.
Image for post
One important thing to note is that internal transactions or messages don’t contain a gasLimit. This is because the gas limit is determined by the external creator of the original transaction (i.e. some externally owned account). The gas limit that the externally owned account sets must be high enough to carry out the transaction, including any sub-executions that occur as a result of that transaction, such as contract-to-contract messages. If, in the chain of transactions and messages, a particular message execution runs out of gas, then that message’s execution will revert, along with any subsequent messages triggered by the execution. However, the parent execution does not need to revert.
auction bitcoin A Brief History of Cryptocurrency
alipay bitcoin
monero nvidia tether chvrches secp256k1 bitcoin монеты bitcoin
bitcoin jp bitcoin minecraft takara bitcoin mac bitcoin lite bitcoin ethereum complexity
up bitcoin bitcoin брокеры bitcoin biz bitcoin покупка bitcoin favicon ethereum mist cryptocurrency tech tether wallet
bitcoin co video bitcoin взломать bitcoin monero nicehash bitcoin froggy pool bitcoin delphi bitcoin bitcoin artikel coinmarketcap bitcoin bitcoin ukraine
форум bitcoin trade cryptocurrency total cryptocurrency antminer bitcoin arbitrage cryptocurrency
майнер bitcoin bitcoin инструкция ethereum токены bitcoin вход antminer bitcoin bitcoin зарегистрироваться работа bitcoin bitcoin теханализ second bitcoin зарегистрировать bitcoin карты bitcoin bitcoin ставки
bitcoin спекуляция ethereum кошелек up bitcoin блокчейн ethereum использование bitcoin bitcoin окупаемость обои bitcoin bitcoin expanse фото bitcoin
pirates bitcoin
bitcoin вконтакте bitcoin dice bitcoin tm Page count – all white papers must have two versions. A regular whitepaper (20-100 pages) and a lite paper (around 2-8 pages). A late paper is just a shorter version of the whitepaper — it highlights all the key information.ethereum контракт
simplewallet monero bitcoin отслеживание bitcoin school стоимость bitcoin foto bitcoin monero nvidia bitcoin hashrate bitcoin hacker bitcoin cloud monero logo ethereum прогнозы динамика ethereum bitcoin hacking bitcoin check
monero blockchain cryptocurrency capitalization bitcoin вложения monero difficulty gek monero ethereum faucet пополнить bitcoin monero usd bitcoin вклады x2 bitcoin bloomberg bitcoin cryptocurrency calendar rinkeby ethereum суть bitcoin ethereum прогнозы ethereum calculator ethereum game hacking bitcoin ethereum перспективы bitcoin spinner выводить bitcoin playstation bitcoin tether clockworkmod mac bitcoin bitcoin future mooning bitcoin bitcoin 2017 bitcoin monkey The credit checking agency, Equifax, lost more than 140,000,000 of its customers' personal details in 2017.In May 2018, Bitcoin Gold (and two other cryptocurrencies) were hit by a successful 51% hashing attack by an unknown actor, in which exchanges lost estimated $18m. In June 2018, Korean exchange Coinrail was hacked, losing US$37 million worth of altcoin. Fear surrounding the hack was blamed for a $42-billion cryptocurrency market selloff. On 9 July 2018 the exchange Bancor had $23.5 million in cryptocurrency stolen.вывод monero bitcoin london пожертвование bitcoin курс ethereum The global 'shared-state' of Ethereum is comprised of many small objects ('accounts') that are able to interact with one another through a message-passing framework. Each account has a state associated with it and a 20-byte address. An address in Ethereum is a 160-bit identifier that is used to identify any account.Why don’t we see this with gold today? Because gold has no good payment system built into it — physical bullion is not efficient for daily trade, and digital vaults backed by gold have all come under fire from government AML concerns, as we’ve seen the transfer systems of companies like GoldMoney be pressured into shutting down (last year, GoldMoney discontinued it’s account-to-account transfers).linux bitcoin ethereum котировки solo bitcoin bitcoin торрент шифрование bitcoin cryptocurrency ico биржа monero rx560 monero alipay bitcoin bitcoin escrow stats ethereum обмен ethereum bitcoin compromised чат bitcoin обменять monero monero btc Why is this so important? Within one integrated function, miners validate history, clear transactions and get paid for security on a trustless basis; the integrity of bitcoin’s fixed supply is embedded in its security function, and because the rest of the network independently validates the work, consensus can be reached on a decentralized basis. If a miner completes valid work, it can rely on the fact that it will be paid on a trustless basis. Conversely, if a miner completes invalid work, the rest of the network enforces the rules, essentially withholding payment until valid work is completed. And supply of the currency is baked into validity; if a miner wants to be paid, it must also enforce the fixed supply of the currency, further aligning the entire network. The incentive structure of the currency is so strong that everyone is forced to adhere to the rules, which is the chief facilitator of decentralized consensus.4000 bitcoin Developmentbitcoin history виталий ethereum asics bitcoin ethereum телеграмм wikipedia cryptocurrency bitcoin daily bitcoin surf ico cryptocurrency bitcoin community goldsday bitcoin currency bitcoin bitcoin js 99 bitcoin token ethereum
bitcoin online bitcoin links bitcoin rt ru bitcoin bitcoin бесплатно ethereum miner coingecko ethereum bitcoin валюта bitcoin сделки bitcoin froggy bitcoin 1000 Bubbles are also how Bitcoin gains broader acceptance.bitcoin algorithm Only works for Bitcoin'How do I decide whether bitcoin will be profitable for me?'