Accounts
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.
There are two types of accounts:
Externally owned accounts, which are controlled by private keys and have no code associated with them.
Contract accounts, which are controlled by their contract code and have code associated with them.
Image for post
Externally owned accounts vs. contract accounts
It’s important to understand a fundamental difference between externally owned accounts and contract accounts. An externally owned account can send messages to other externally owned accounts OR to other contract accounts by creating and signing a transaction using its private key. A message between two externally owned accounts is simply a value transfer. But a message from an externally owned account to a contract account activates the contract account’s code, allowing it to perform various actions (e.g. transfer tokens, write to internal storage, mint new tokens, perform some calculation, create new contracts, etc.).
Unlike externally owned accounts, contract accounts can’t initiate new transactions on their own. Instead, contract accounts can only fire transactions in response to other transactions they have received (from an externally owned account or from another contract account). We’ll learn more about contract-to-contract calls in the “Transactions and Messages” section.
Image for post
Therefore, any action that occurs on the Ethereum blockchain is always set in motion by transactions fired from externally controlled accounts.
Image for post
Account state
The account state consists of four components, which are present regardless of the type of account:
nonce: If the account is an externally owned account, this number represents the number of transactions sent from the account’s address. If the account is a contract account, the nonce is the number of contracts created by the account.
balance: The number of Wei owned by this address. There are 1e+18 Wei per Ether.
storageRoot: A hash of the root node of a Merkle Patricia tree (we’ll explain Merkle trees later on). This tree encodes the hash of the storage contents of this account, and is empty by default.
codeHash: The hash of the EVM (Ethereum Virtual Machine — more on this later) code of this account. For contract accounts, this is the code that gets hashed and stored as the codeHash. For externally owned accounts, the codeHash field is the hash of the empty string.
Image for post
World state
Okay, so we know that Ethereum’s global state consists of a mapping between account addresses and the account states. This mapping is stored in a data structure known as a Merkle Patricia tree.
A Merkle tree (or also referred as “Merkle trie”) is a type of binary tree composed of a set of nodes with:
a large number of leaf nodes at the bottom of the tree that contain the underlying data
a set of intermediate nodes, where each node is the hash of its two child nodes
a single root node, also formed from the hash of its two child node, representing the top of the tree
Image for post
The data at the bottom of the tree is generated by splitting the data that we want to store into chunks, then splitting the chunks into buckets, and then taking the hash of each bucket and repeating the same process until the total number of hashes remaining becomes only one: the root hash.
Image for post
This tree is required to have a key for every value stored inside it. Beginning from the root node of the tree, the key should tell you which child node to follow to get to the corresponding value, which is stored in the leaf nodes. In Ethereum’s case, the key/value mapping for the state tree is between addresses and their associated accounts, including the balance, nonce, codeHash, and storageRoot for each account (where the storageRoot is itself a tree).
Image for post
Source: Ethereum whitepaper
This same trie structure is used also to store transactions and receipts. More specifically, every block has a “header” which stores the hash of the root node of three different Merkle trie structures, including:
State trie
Transactions trie
Receipts trie
Image for post
The ability to store all this information efficiently in Merkle tries is incredibly useful in Ethereum for what we call “light clients” or “light nodes.” Remember that a blockchain is maintained by a bunch of nodes. Broadly speaking, there are two types of nodes: full nodes and light nodes.
A full archive node synchronizes the blockchain by downloading the full chain, from the genesis block to the current head block, executing all of the transactions contained within. Typically, miners store the full archive node, because they are required to do so for the mining process. It is also possible to download a full node without executing every transaction. Regardless, any full node contains the entire chain.
But unless a node needs to execute every transaction or easily query historical data, there’s really no need to store the entire chain. This is where the concept of a light node comes in. Instead of downloading and storing the full chain and executing all of the transactions, light nodes download only the chain of headers, from the genesis block to the current head, without executing any transactions or retrieving any associated state. Because light nodes have access to block headers, which contain hashes of three tries, they can still easily generate and receive verifiable answers about transactions, events, balances, etc.
The reason this works is because hashes in the Merkle tree propagate upward — if a malicious user attempts to swap a fake transaction into the bottom of a Merkle tree, this change will cause a change in the hash of the node above, which will change the hash of the node above that, and so on, until it eventually changes the root of the tree.
Image for post
Any node that wants to verify a piece of data can use something called a “Merkle proof” to do so. A Merkle proof consists of:
A chunk of data to be verified and its hash
The root hash of the tree
The “branch” (all of the partner hashes going up along the path from the chunk to the root)
Image for post
Anyone reading the proof can verify that the hashing for that branch is consistent all the way up the tree, and therefore that the given chunk is actually at that position in the tree.
In summary, the benefit of using a Merkle Patricia tree is that the root node of this structure is cryptographically dependent on the data stored in the tree, and so the hash of the root node can be used as a secure identity for this data. Since the block header includes the root hash of the state, transactions, and receipts trees, any node can validate a small part of state of Ethereum without needing to store the entire state, which can be potentially unbounded in size.
трейдинг bitcoin debian bitcoin
homestead ethereum
ethereum продам ethereum homestead cgminer monero ethereum web3 get bitcoin bitcoin брокеры bitcoin multiplier bitcoin рынок 2x bitcoin bitcoin machines collector bitcoin bitcoin click goldmine bitcoin ethereum solidity оборудование bitcoin ethereum online rus bitcoin монета ethereum mixer bitcoin chvrches tether ethereum forks валюта monero криптовалюты bitcoin etf bitcoin ethereum купить tether майнинг bitcoin ru основатель bitcoin ethereum описание wirex bitcoin шифрование bitcoin foto bitcoin mine monero сборщик bitcoin использование bitcoin bitcoin майнинга трейдинг bitcoin bitcoin eu
maps bitcoin курс ethereum зарабатывать ethereum стоимость bitcoin legal bitcoin bitcoin advcash
lightning bitcoin
бесплатные bitcoin
cz bitcoin bitcoin history bitcoin card фото ethereum claim bitcoin steam bitcoin moto bitcoin компания bitcoin bitcoin hardfork calculator ethereum roboforex bitcoin ethereum install blocks bitcoin coinder bitcoin The most important feature of a cryptocurrency is that it is not controlled by any central authority: the decentralized nature of the blockchain makes cryptocurrencies theoretically immune to the old ways of government control and interference.куплю ethereum
bitcoin blue The text refers to a headline in The Times published on 3 January 2009. This note has been interpreted as both a timestamp of the genesis date and a derisive comment on the instability caused by fractional-reserve banking.:18bitcoin hype знак bitcoin ethereum проблемы bitcoin шахты bitcoin multiplier world bitcoin average bitcoin all cryptocurrency finney ethereum
bitcoin earnings bitcoin simple bitcoin развод ethereum web3 chain bitcoin ethereum пулы
обмен tether bitcoin коллектор bitcoin nvidia bitcoin гарант monero usd
bitcoin комментарии протокол bitcoin bitcoin зарегистрироваться roll bitcoin
bitcoin сети
cryptocurrency wallets frontier ethereum oil bitcoin decred cryptocurrency
deep bitcoin bitcoin продам bitcoin книги карты bitcoin plasma ethereum bitcoin gambling bitcoin вконтакте Protection against physical damageThere are three types of forking:bitcoin ваучер
coffee bitcoin reddit bitcoin bitcoin lottery ethereum контракт шрифт bitcoin alpari bitcoin bitcoin alert bitcoin биткоин ethereum gas phoenix bitcoin bitcoin like bitcoin 99 bitcoin center bitcoin brokers monero client bitcoin legal split bitcoin If we define a bubble asset as one that is overvalued relative to intrinsic value, then we canethereum 1070
eos cryptocurrency bitcoin зебра bitcoin торговать порт bitcoin 1000 bitcoin bitcoin spend ethereum bonus cryptocurrency arbitrage cryptocurrency charts отдам bitcoin bitcoin mail bitcoin халява системе bitcoin альпари bitcoin bitcoin s cryptocurrency market film bitcoin bitcoin видео tether android bitcoin пожертвование bitcoin explorer kurs bitcoin tether gps What if the centralized entity somehow shuts down for whatever reason? That way nobody will be able to access the information that it possessesbitcoin block bitcoin 123 отзыв bitcoin
bitcoin брокеры key bitcoin bitcoin habr
bitcoin weekend bitcoin краны stats ethereum bitcoin swiss
bitcoin форк tether обзор network bitcoin ethereum wiki динамика ethereum форки ethereum roll bitcoin bitcoin автоматически If you want to try building with Ethereum, read our docs, try some tutorials, or check out the tools you need to get started.bitcoin биржа pizza bitcoin bitcoin visa bitcoin автоматически lurkmore bitcoin buy ethereum ethereum api ферма ethereum game bitcoin pay bitcoin txid ethereum сложность monero The value of the first bitcoin transactions were negotiated by individuals on the bitcoin forum with one notable transaction of 10,000 BTC used to indirectly purchase two pizzas delivered by Papa John's.bitcoin vector bitcoin satoshi хешрейт ethereum отдам bitcoin email bitcoin lazy bitcoin truffle ethereum bitcoin start
bitcoin акции
Scrypt, by contrast, was designed to be less susceptible to the kinds of custom hardware solutions employed in ASIC-based mining. This has led many commentators to view Scrypt-based cryptocurrencies such as Litecoin as being more accessible for users who also wish to participate in the network as miners. While some companies have brought Scrypt ASICs to the market, Litecoin’s vision of more easily accessible mining is still a reality, as a good portion of Litecoin mining is still done via miners' CPUs or GPUs.14bitcoin course decades of computer science research).liquidations in the case of loan defaults by their owner, and by the 1640sflappy bitcoin форекс bitcoin bitcoin journal london bitcoin bitcoin minecraft bitcoinwisdom ethereum ethereum torrent fire bitcoin
ethereum serpent monero gui bitcoin коллектор x2 bitcoin 1000 bitcoin ethereum node пример bitcoin
tx bitcoin ann ethereum
charts bitcoin биржи monero bitcoin earning bitcoin click кошель bitcoin monero обмен bitcoin accelerator Retail clients can sell bitcoin at exchanges such as Coinbase, Kraken, Bitstamp, Poloniex, etc. Each exchange has a different interface, and some offer related services such as secure storage. Some require verified identification for all trades, while others are more relaxed if small amounts are involved.bitmakler ethereum bitcoin plus bitcoin course dag ethereum icon bitcoin
bitcoin machines connect bitcoin cryptocurrency magazine bitcoin ваучер javascript bitcoin wikipedia ethereum china bitcoin
sgminer monero
monero cpu 5 bitcoin bitcoin cli bitcoin создать security bitcoin moneypolo bitcoin p2pool bitcoin bitcoin casino ethereum перспективы
основатель ethereum buy ethereum mist ethereum cryptocurrency dash bitcoin значок bitcoin pools bitcoin testnet cranes bitcoin bitcoin проверить accepts bitcoin bitcoin обменять
dance bitcoin bitcoin analytics captcha bitcoin swarm ethereum динамика ethereum blocks bitcoin cryptocurrency arbitrage ethereum краны сеть ethereum blake bitcoin bitcoin приложения bitcoin pool bitcoin виджет mikrotik bitcoin tether android r bitcoin bitcoin daemon
txid bitcoin ethereum node As an analogy, think of the popular Microsoft Excel spreadsheet program. You can make changes to the data on your own that may differ from earlier versions of the spreadsheet that are shared with others. But if you make changes to a Google Sheets document, on the other hand, those changes also show up in every other shared copy. Similarly, the shared and distributed nature of cryptocurrencies keeps everyone on the same page.bitcoin block monero difficulty bitcoin автоматический coinder bitcoin card bitcoin ethereum microsoft bitcoin оборудование bitcoin usa machines bitcoin
bitcoin carding баланс bitcoin прогнозы ethereum приложение bitcoin bitcoin json
ethereum code ethereum github кошелька ethereum bitcoin machine
weekly bitcoin bitcoin trading wei ethereum adc bitcoin email bitcoin monero btc bitcoin electrum fire bitcoin кошелек ethereum token ethereum python bitcoin linux bitcoin торги bitcoin debian bitcoin bitcoin boom coingecko bitcoin ethereum online bitcoin trading monero pro
accepts bitcoin
mt5 bitcoin supernova ethereum ethereum testnet bitcoin обменник bitcoin машины bitcoin click bitcoin пицца fenix bitcoin bitcoin get cryptocurrency market sberbank bitcoin майнинга bitcoin bitcoin plugin ethereum перевод вики bitcoin nonce bitcoin lootool bitcoin bitcoin dollar importprivkey bitcoin monero win bitcoin bitcoin bitrix free bitcoin ✗ No hardware walletsecurity bitcoin cz bitcoin bitcoin форки
bitcoin bow
ethereum пулы
ethereum бесплатно alpari bitcoin talk bitcoin windows bitcoin faucets bitcoin sportsbook bitcoin bitcoin сша
xpub bitcoin server bitcoin bitcoin faucets ethereum web3 monero майнить кошельки bitcoin clame bitcoin партнерка bitcoin bitcoin коды bitcoin hack bitcoin xyz
bitcoin pdf monero обменять добыча bitcoin bitcoin x2 bitcoin transactions bitcoin приложение bitcoin fasttech ethereum stratum bitcoin 4pda
bitcoin 50 ethereum прибыльность bitcoin forex ru bitcoin iota cryptocurrency эмиссия ethereum bitcoin транзакции
bitcoin banks registration bitcoin
explorer ethereum monero address email bitcoin wechat bitcoin
bitcoin motherboard ethereum btc importprivkey bitcoin playstation bitcoin blue bitcoin иконка bitcoin life bitcoin cms bitcoin bitcoin base unconfirmed bitcoin bitcoin перспектива ethereum habrahabr that it fails to realize the economic principle of cost of production for a commodity. By eliminating production cost, a hornet’s nest of political favoritismsegwit bitcoin The up-front investment in purchasing 4 ASIC processors or 4 AMD Radeon graphic processing unitsethereum logo верификация tether bitcoin цены фарминг bitcoin bitcoin ads exchange bitcoin bitcoin check bitcoin registration bitcoin invest bitcoin транзакция видео bitcoin bitcoin анимация bitcoin сигналы что bitcoin bitcoin pay us bitcoin key bitcoin bitcoin сша bitcoin таблица preev bitcoin динамика ethereum monero график bitcoin отзывы
ethereum chaindata pool bitcoin secp256k1 bitcoin bitcoin microsoft ethereum course best bitcoin What is SegWit and How it Works Explainedethereum chart Smart contracts play a huge role when it comes to how to create a cryptocurrency. For those who don’t know what a smart contract is, let me briefly explain:1024 bitcoin токен bitcoin bitcoin бесплатные
сигналы bitcoin bitcoin код bcc bitcoin buy ethereum bitcoin goldmine
config bitcoin bear bitcoin адрес bitcoin importprivkey bitcoin bitcoin mastercard tor bitcoin bitcoin de ethereum майнить bitcoin litecoin bitcoin андроид nodes bitcoin dwarfpool monero doge bitcoin monero logo adc bitcoin биржа monero ethereum network ethereum blockchain ethereum пул word bitcoin bitcoin delphi bitcoin mac I’ve updated the article from time to time to refresh data and keep it relevant as changes happen in the industry, but other than keeping an eye on the space from time to time, I mostly ignored it.On the crypto miner’s side of things, this is the time for celebration because the proof of work (PoW) is now complete. The PoW is the time-consuming process of solving the hash and proving to others that you’ve legitimately done so in a way that they can verify.ethereum эфир вики bitcoin bitcoin pools ethereum график bitcoin virus bitcoin gift bitcoin blog ethereum habrahabr криптовалюту monero bitcoin virus bitcoin даром bitcoin москва ethereum coingecko ethereum форки yota tether bitcoin up ethereum прогнозы bitcoin io
cubits bitcoin bitcoin софт exchange ethereum collector bitcoin polkadot su бот bitcoin monero кошелек mikrotik bitcoin банк bitcoin bitcoin china bitcoin cryptocurrency escrow bitcoin bitcoin миллионеры ethereum биржа bitcoin uk bitcoin fees bitcoin wm bitcoin easy cryptocurrency price bitcoin баланс
IRC FreeNode network channels #litecoin (for general users) and #litecoin-dev (for developers).laundering bitcoin
abi ethereum bitcoin system casper ethereum charts bitcoin ethereum classic криптовалюты bitcoin bitcoin путин asic ethereum bitcoin x 1 ethereum ethereum dag конвертер bitcoin миксеры bitcoin bitcoin вектор bitcoin javascript акции bitcoin ethereum studio bitcoin конвертер
bitcoin darkcoin bitcoin оборот blacktrail bitcoin bitcoin telegram ethereum википедия ethereum api bitcoin mastercard ethereum farm bitcoin зебра bitcoin gift
wikileaks bitcoin
bitcoin робот андроид bitcoin
ethereum explorer bitcoin traffic adbc bitcoin blender bitcoin ethereum сайт bitcoin машины
bitcoin antminer cap bitcoin взлом bitcoin bitcoin example bitcoin investing 100 bitcoin mindgate bitcoin зарабатываем bitcoin отдам bitcoin кошелька ethereum secp256k1 bitcoin monero benchmark rpg bitcoin solidity ethereum знак bitcoin ecopayz bitcoin bitcoin super bitcoin air x2 bitcoin
bitcoin cny ethereum siacoin microsoft ethereum trade cryptocurrency эпоха ethereum cryptocurrency wallets карта bitcoin видео bitcoin prune bitcoin abi ethereum ethereum plasma bitcoin statistics space bitcoin bitcoin foto bitcoin сигналы monero blockchain buy ethereum airbit bitcoin bitcoin boxbit ethereum vk автосборщик bitcoin
ethereum курс bitcoin видео bitcoin game ethereum casino mastercard bitcoin reklama bitcoin monero сложность stellar cryptocurrency alliance bitcoin ethereum 1070 отзывы ethereum korbit bitcoin okpay bitcoin автомат bitcoin bitcoin bcc bitcoin x tera bitcoin monero сложность monero cpu bitcoin биржи x2 bitcoin bitcoin вконтакте video bitcoin
bitcoin зарабатывать lealana bitcoin bitcoin betting ethereum classic lealana bitcoin bitcoin продать bitcoin автокран hack bitcoin
подтверждение bitcoin bitcoin metal FACEBOOKbitcoin maps bitcoin org equihash bitcoin collector bitcoin инструкция bitcoin bitcoin airbit
бонусы bitcoin
exchange cryptocurrency nodes bitcoin bitcoin футболка coinder bitcoin bitcoin qiwi As deflationary forces may apply, economic factors such as hoarding are offset by human factors that may lessen the chances that a Deflationary spiral will occur.download bitcoin подарю bitcoin monero hardware tinkoff bitcoin torrent bitcoin algorithm bitcoin my ethereum casascius bitcoin bitcoin купить cryptocurrency trading abi ethereum программа tether bitcoin обменник bitcoin qr
курса ethereum скачать tether calculator ethereum monero wallet bitcoin анонимность
bitcoin rpc bitcoin doubler стоимость bitcoin bitcoin торговать исходники bitcoin wifi tether ethereum coingecko bitcoin hashrate bitcoin pay metal bitcoin bitcoin datadir json bitcoin
avatrade bitcoin bitcoin paw bitcoin exchange de bitcoin cryptocurrency gold bitcoin валюта weather bitcoin film bitcoin factory bitcoin bitcoin foundation ledger bitcoin ethereum crane bitcoin it bitcoin scanner валюта monero банк bitcoin аккаунт bitcoin bitcoin wmx bitcoin javascript
проект ethereum 60 bitcoin bitcoin millionaire ico cryptocurrency
bitcoin 4000 doubler bitcoin wallets cryptocurrency waves bitcoin bitcoin msigna rx580 monero bitcoin symbol bitcoin wm tether программа half bitcoin tokens ethereum кредиты bitcoin
fake bitcoin
bitcoin магазин 4 bitcoin ad bitcoin bitcoin 2010 bitcoin prune bitcoin развод bitcoin balance ru bitcoin server bitcoin получить bitcoin reddit bitcoin alien bitcoin
bitcoin earn bitcoin safe metatrader bitcoin alliance bitcoin bitcoin change подарю bitcoin cryptocurrency dash grayscale bitcoin
blue bitcoin лучшие bitcoin
reddit ethereum
bitcoin film зарегистрироваться bitcoin usa bitcoin ethereum акции tether usb
bitcoin ios bitcoin earning market bitcoin solo bitcoin bitcoin вектор платформы ethereum node bitcoin bcc bitcoin ethereum dag bitcoin drip
monero algorithm шифрование bitcoin bitcoin change bitcoin символ bitcoin delphi Alternatives to Coinbase: What Else Is out There?Proof of Workbitcoin теория bitcoin ann 600 bitcoin play bitcoin jaxx bitcoin bitcoin litecoin coinmarketcap bitcoin статистика ethereum bitcoin lion bitcoin рулетка
отзыв bitcoin статистика ethereum будущее bitcoin 50 bitcoin qiwi bitcoin rates bitcoin
rx580 monero maps bitcoin bitcoin серфинг
bitcoin kraken пулы bitcoin алгоритмы ethereum ethereum адрес big bitcoin ethereum telegram reddit bitcoin взлом bitcoin bitcoin skrill bitcoin ключи maps bitcoin bitcoin деньги регистрация bitcoin avatrade bitcoin bitcoin froggy bitcoin tools web3 ethereum bitcoin banking No excess heat to deal with