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.
bitcoin payza greenaddress bitcoin It’s easy to find tales of those who found Bitcoin early on but who sold toobitcoin обменять bitcoin приват24 bitcoin etf delphi bitcoin blue bitcoin short bitcoin bus bitcoin monero client разработчик ethereum ethereum курсы торги bitcoin dark bitcoin bitcoin roll
keystore ethereum
bitcoin london nxt cryptocurrency бумажник bitcoin shot bitcoin bitcoin plugin bitcoin войти best cryptocurrency ethereum io bitcoin форумы bitfenix bitcoin
stellar cryptocurrency wirex bitcoin bitcoin valet charts bitcoin moon ethereum bitcoin easy Bitcoin also has a stipulation—set forth in its source code—that it must have a limited and finite supply. For this reason, there will only ever be 21 million bitcoins ever produced. On average, these bitcoins are introduced to the bitcoin supply at a fixed rate of one block every ten minutes. In addition, the amount of bitcoin released in each of these aforementioned blocks is reduced by 50% every four years.case bitcoin bitcoin gif bitcoin алгоритм In the case that the sender does not provide the necessary gas to execute the transaction, the transaction runs 'out of gas' and is considered invalid. In this case, the transaction processing aborts and any state changes that occurred are reversed, such that we end up back at the state of Ethereum prior to the transaction. Additionally, a record of the transaction failing gets recorded, showing what transaction was attempted and where it failed. And since the machine already expended effort to run the calculations before running out of gas, logically, none of the gas is refunded to the sender.monero xmr ann monero casinos bitcoin market bitcoin bitcoin database When you ask yourself, 'Should I buy Litecoin or Ethereum?', you’re asking what is more valuable to you:monaco cryptocurrency capitalization bitcoin blue bitcoin claymore monero bitcoin widget проект bitcoin ethereum пулы gas ethereum car bitcoin monero курс bitcoin trading создатель bitcoin bitcoin qiwi tether chvrches
bitcoin начало
bitcoin in mist ethereum ethereum продать trade cryptocurrency bitcoin half metatrader bitcoin btc ethereum 777 bitcoin
bitcoin рейтинг bitcoin видеокарты шахта bitcoin
новости monero
avto bitcoin mt5 bitcoin space bitcoin вебмани bitcoin zone bitcoin bitcoin greenaddress bitcoin in
ethereum pools trade cryptocurrency ethereum news пул bitcoin карты bitcoin monero hashrate tether обменник валюта tether
1 ethereum rigname ethereum Bitcoinmonero miner bitcoin flapper parity ethereum bitcoin venezuela monero пул bitcoin trader bitcoin капитализация monero pools кран bitcoin скачать bitcoin bitcoin комиссия hardware bitcoin amazon bitcoin алгоритм monero платформу ethereum bitcoin проблемы bitcoin plus bitcoin visa tether bootstrap ethereum difficulty ethereum mine bitcoin future wei ethereum bitcoin форк
ethereum mine script bitcoin iobit bitcoin bitcointalk ethereum api bitcoin bitcoin сатоши работа bitcoin bitcoin loto bitcoin game api bitcoin maps bitcoin ethereum пулы сборщик bitcoin poloniex bitcoin bitcoin котировка bitcoin planet андроид bitcoin bitcoin s
coinmarketcap bitcoin bitcoin blue ethereum википедия magic bitcoin finney ethereum withdraw bitcoin bitcoin charts ethereum pools bitcoin adress ethereum виталий bitcoin monkey tor bitcoin monaco cryptocurrency ethereum сайт sberbank bitcoin bitcoin token отзывы ethereum bitcoin hash battle bitcoin
bitcoin расчет bitcoin компания bitcoin exchanges block ethereum goldmine bitcoin заработок ethereum bitcoin автоматически keys bitcoin p2pool ethereum
tether usd bitcoin scanner coinmarketcap bitcoin magic bitcoin txid ethereum In networked environments (like the world of cryptocurrencies), new developments tend to follow a power law distribution; there are a few clear,bitcoin download bitcoin видеокарты an end-user who is sending and receiving cryptocurrency transactions. All stakeholders are typically wallet users if they hold the coin. Many wallets are light clients who trust a copy of the ledger stored by the Third Party Developer of the wallet.It can take about two minutes to mine one coin, although there is no maximum block size.1bitcoin авито график bitcoin How Bitcoins Are Trackeddisk/bandwidth won’t scale20bitcoin motherboard status bitcoin bitcoin алгоритм simplewallet monero bitcoin подтверждение advcash bitcoin ann monero bitcoin spinner monero amd forex bitcoin биржа bitcoin Gold in particular is rare and pretty, extremely resistant to reaction (i.e. it lasts forever), and easily malleable into coins and bars, which made it pretty much perfect as a form of money, at least until the modern age. It’s no longer practical or even possible to walk around paying gold and silver for things you want to buy, unless government currencies go back to using a direct gold standard. It also has plenty of industrial use due to its chemical properties, but its price level keeps most of its use for money and jewelry.Wallets and similar software technically handle all bitcoins as equivalent, establishing the basic level of fungibility. Researchers have pointed out that the history of each bitcoin is registered and publicly available in the blockchain ledger, and that some users may refuse to accept bitcoins coming from controversial transactions, which would harm bitcoin's fungibility. For example, in 2012, Mt. Gox froze accounts of users who deposited bitcoins that were known to have just been stolen.These events are called 'halvings'. The launch period (first cycle) had 50 new bitcoins every 10 minutes. The first halving occurred in November 2012, and from that point on (second cycle), miners only received 25 coins for solving a block. The second halving occurred in July 2016, and from there (third cycle) the reward fell to 12.5 new coins per block. The third halving just occurred in May 2020 (fourth cycle), and so the reward is now just 6.25 coins per new block.monero asic This article provides a few frameworks to help you think about how to determine Bitcoin’s value for yourself, and the value of other cryptocurrencies, including explaining a lot of the risks involvedbitcoin оборудование hourly bitcoin bitcoin usa cryptocurrency dash bitcoin anonymous bitcoin sphere payoneer bitcoin tether пополнение moneybox bitcoin usa bitcoin покер bitcoin 99 bitcoin bitcoin в калькулятор bitcoin сборщик bitcoin bitcoin betting buying bitcoin
bitcoin рбк mac bitcoin fx bitcoin команды bitcoin шахта bitcoin ethereum eth значок bitcoin bitcoin betting and there is no central point of failure.bitcoin hunter
bitcoin коды bitcoin работать ethereum 4pda bitcoin msigna doubler bitcoin monero курс bitcoin symbol 20 bitcoin ethereum stats monero miner adbc bitcoin bitcoin safe bitcoin get game bitcoin киа bitcoin decred ethereum xpub bitcoin earn bitcoin bitcoin казахстан bitcoin рейтинг отзыв bitcoin bitcoin 15
bitcoin dance cryptocurrency charts bitcoin проблемы
форк ethereum monero windows bitcoin bazar bitcoin buying bitcoin биржа настройка monero 2x bitcoin bitcoin auction bitcoin sweeper настройка monero earn bitcoin app bitcoin бесплатно ethereum bitcoin cpu dice bitcoin ethereum отзывы neo cryptocurrency circle bitcoin bitcoin япония cryptocurrency calculator поиск bitcoin fast bitcoin bitcoin neteller bitcoin rpg wallet cryptocurrency bitcoin utopia You can join Ethereum mining pools like Ethpool, F2Pool, and DwarfPool to split the responsibilities and rewards of running the blockchain with other users.ethereum стоимость hd7850 monero monero coin
bitcoin converter приложение tether bitcoin ставки
bubble bitcoin bitcoin office bitcoin sha256 tether программа bitcoin динамика in bitcoin stock bitcoin bitcoin frog сколько bitcoin bitcoin прогноз pro100business bitcoin bitcoin reindex bitcoin отслеживание асик ethereum bitcoin скачать bitcoin cny bitcointalk bitcoin
bitcoin video all cryptocurrency ethereum addresses bitcoin prune 2016 bitcoin moon ethereum bitcoin conveyor bitcoin программирование pdf bitcoin ethereum node bcn bitcoin валюта monero payable ethereum
bitcoin buying bitcoin видеокарты alpha bitcoin вывести bitcoin пример bitcoin proxy bitcoin segwit2x bitcoin ethereum coin
bitcoin дешевеет byzantium ethereum
bitcoin кошелька bitcoin tools бесплатно bitcoin monero logo bitcoin symbol bitcoin io bitcoin algorithm tether wifi bitcoin программа bitcoin algorithm atm bitcoin bitcoin hardfork monero график
ферма bitcoin bitcoin сайты bitcoin multiplier bitcoin solo china bitcoin bitcoin magazin forum ethereum vps bitcoin bittrex bitcoin
abi ethereum вывод monero bitcoin рулетка mail bitcoin monero fr bitcoin earn bitcoin ru ccminer monero bitcoin ротатор simplewallet monero bitcoin multisig коды bitcoin tether приложение short bitcoin collector bitcoin ethereum обмен bitcoin продать bitcoin fan
bitcoin деньги up bitcoin bitcoin inside coinbase ethereum суть bitcoin bitcoin it bitcoin статья логотип bitcoin cryptocurrency calendar tether верификация bitcoin service обменник bitcoin ethereum markets вход bitcoin vpn bitcoin ethereum сбербанк bitcoin краны проверка bitcoin monero cpu monero dwarfpool bitcoin stealer bitcoin euro bitcoin коллектор
kran bitcoin
bitcoin разделился bitcoin stealer
monero ico bitcoin get bitcoin advcash bitcoin ваучер раздача bitcoin перевод ethereum 8 bitcoin account bitcoin hack bitcoin bitcoin multisig bitcoin up tether майнинг bank bitcoin ethereum forks bitcoin airbit bitcoin кликер bitcoin dat matteo monero bitcoin blog get bitcoin bitcoin tools bitcoin loan сколько bitcoin 99 bitcoin ethereum raiden daemon monero bitcoin get x bitcoin btc ethereum siiz bitcoin торрент bitcoin bitcoin monero ethereum nicehash bitcoin комиссия ethereum gold bitcoin trinity bitcoin json casper ethereum bubble bitcoin rise cryptocurrency asics bitcoin bitcoin delphi bitcoin москва
отследить bitcoin monero xmr amazon bitcoin platinum bitcoin bitcoin hype ethereum заработать бумажник bitcoin
сервера bitcoin отследить bitcoin best bitcoin
робот bitcoin клиент ethereum
bot bitcoin bitcoin check etoro bitcoin testnet bitcoin ico monero bitcoin hyip nubits cryptocurrency locate bitcoin ethereum calculator ethereum купить ethereum заработок ethereum продам bitcoin conference testnet bitcoin обмен monero понятие bitcoin auto bitcoin bitcoin код magic bitcoin box bitcoin bitcoin zona майнер monero monero fee автоматический bitcoin bitcoin tools ethereum dark bitcoin cz bitcoin okpay
ethereum алгоритм monero сложность bitcoin s получить bitcoin multibit bitcoin ethereum price apple bitcoin
bitcoin официальный bitcoin программирование bitcoin php monero node
mining monero bitcoin greenaddress bitcoin оборот flappy bitcoin
sha256 bitcoin обмен tether bitcoin accelerator bitcoin scripting трейдинг bitcoin capitalization bitcoin bitcoin трейдинг bitcoin plus double bitcoin bitcoin analytics bitcoin plugin bitcoin программа zebra bitcoin ethereum новости gui monero tails bitcoin ethereum studio card bitcoin bitcoin telegram зарабатывать bitcoin purse bitcoin ethereum акции ethereum swarm
matteo monero bitcoin debian bitcoin scam bitcoin uk bitcoin кошелька nya bitcoin bitcoin официальный bitcoin me bitcoin bitcointalk bitcoin conf bitcoin игры java bitcoin bitcoin foto
ethereum dark hd7850 monero ethereum price 'Why is it emerging now?'bitcoin книга bitcoin metatrader koshelek bitcoin bitcoin tradingview bitcoin rotator
пирамида bitcoin 4000 bitcoin However, there are several important deviations from those assumptions in reality:We have established that miners receive the lion’s share of wealth created by the Bitcoin network, and as a result, miners may become large sources of development capital. Many large-scale miners also manufacture machines, operate mining pools for other miners at a small fee.bitcoin инструкция wikipedia cryptocurrency bitcoin club dogecoin bitcoin обменники bitcoin bitcoin check bitcoin uk калькулятор bitcoin cryptocurrency wallet
ethereum хардфорк fpga ethereum reward bitcoin lealana bitcoin ethereum vk micro bitcoin buy ethereum tether chvrches bitcoin видеокарты
film bitcoin bitcoin pps полевые bitcoin service bitcoin скрипт bitcoin bitcoin doge bitcoin xt bitcoin заработок обвал bitcoin For these reasons and others, Robert R. Johnson, PhD, CFA, CAIA and Professor of Finance at Heider College of Business, Creighton University, says that Bitcoin and other cryptocurrencies are 'the purview of speculators.' No one should consider buying Bitcoin or any other cryptocurrency as an investment, he says.сервисы bitcoin криптовалюта tether
pixel bitcoin amd bitcoin monero купить bitcoin symbol bitcoin fpga bitcoin pro запуск bitcoin hacking bitcoin swiss bitcoin транзакции bitcoin
bitcoin сборщик cryptocurrency wallets 3 bitcoin