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.
ethereum investing CPUbitcoin weekly bitcoin фарминг icon bitcoin обмена bitcoin bitcoin хабрахабр bitcoin wm
bitcoin gadget
bitcoin exchanges moneybox bitcoin ethereum pow bitcoin dat daemon bitcoin bitcoin config bitcoin foto bitcoin ledger bitcoin easy ethereum coin client bitcoin bitcoin книга bitcoin it мониторинг bitcoin goldmine bitcoin bitcoin knots xbt bitcoin bitcoin лохотрон
bitcoin addnode bitcoin data block bitcoin cryptocurrency wallet проекты bitcoin биржи ethereum
tether android up bitcoin tether android bitcoin best котировки ethereum
депозит bitcoin ethereum core raspberry bitcoin r bitcoin fork bitcoin keystore ethereum my ethereum покупка ethereum
надежность bitcoin bitcoin lucky bitcoin сбор взлом bitcoin tether пополнить the ethereum reddit bitcoin js bitcoin source bitcoin bitcoin conference верификация tether котировка bitcoin обменник bitcoin биржи ethereum bitcoin лохотрон bitcoin fake bitcoin evolution bitcoin redex jaxx bitcoin avatrade bitcoin bitcoin motherboard But, he says you don't have to listen to him. Instead, Johnson says to listen to Berkshire Hathaway BRK.B +2% Vice Chairman Charlie Munger who is famous for sharing his thoughts on investing in cryptocurrency:робот bitcoin bitcoin майнер стратегия bitcoin spots cryptocurrency
ethereum alliance переводчик bitcoin
bitcoin vps bitcoin buy
bitcoin 2010 bitcoin bitcoin 4000 bitcoin видеокарты bitcoin world abi ethereum 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 Who Mines Cryptocurrency?As a result, most crypto mining these days is done by companies that specialize in it, or by large groups of individuals who all contribute their computing power.On the other hand, technologists –- nerds — are transfixed by it. They see within it enormous potential and spend their nights and weekends tinkering with it.video bitcoin транзакции ethereum ✓ Anonymous — you don’t need to use your name;future bitcoin This is quite a difficult question to answer accurately. One approach is to count how many bitcoin clients connected to the network in the last 24 hours. We can do this because some clients transmit their addresses to the other members of the network periodically;ethereum продам Going through the gateway of zero into the realms of negative and imaginary numbers provides a more continuous form of logic when compared to the discrete either-or logic, commonly accredited to Aristotle and his followers. This framework is less 'black and white' than the binary Aristotelean logic system, which was based on true or false, and provides many gradations of logicality; a more accurate map to the many 'shades of grey' we find in nature. Continuous logic is insinuated throughout the world: for instance, someone may say 'she wasn’t unattractive,' meaning that her appeal was ambivalent, somewhere between attractive and unattractive. This perspective is often more realistic than a binary assessment of attractive or not attractive.ethereum проблемы bitcoin доходность alpha bitcoin ethereum mist bitcoin анимация film bitcoin ethereum stats multiply bitcoin bitcoin trading lamborghini bitcoin
ethereum stats lamborghini bitcoin The exact number of Bitcoin nodes is unknown, but some sources estimate it to be upwards of 100,000! Imagine trying to hack half of that!deep bitcoin
bitcoin миллионеры bitcoin froggy monero proxy bitcoin шахта amazon bitcoin
mac bitcoin download bitcoin
bitcoin options валюта tether эпоха ethereum робот bitcoin бесплатно ethereum
polkadot stingray bitcoin оборот machine bitcoin ethereum майнеры bitcoin cryptocurrency the ethereum bitcoin программа wiki ethereum bitcoin yandex poker bitcoin робот bitcoin bitcoin 3 bitcoin neteller автомат bitcoin cryptocurrency mining
wikileaks bitcoin
bitcoin greenaddress top cryptocurrency short bitcoin bitcoin лайткоин арбитраж bitcoin миксер bitcoin bitcoin trader golang bitcoin sgminer monero digi bitcoin That is correct.secp256k1 ethereum сложность ethereum cz bitcoin grayscale bitcoin coindesk bitcoin all cryptocurrency bitcoin динамика
ethereum io blog bitcoin bitcoin биткоин PeepEth: PeepEth is a decentralized Twitter alternative. Twitter has the ability to delete accounts and tweets if the company finds them unfavorable. PeepEth is different: although moderators keep the main feed to free of spam and inappropriate posts, 'peeps' posted to PeepEth cannot be deleted. bitcoin 1000 ethereum форки Given the popularity of perpetual issuance systems in new launches, a rough consensus appears to be emerging that attaining sufficient volume for a robust fee market to develop is too challenging an objective for an upstart chain.Backup your wallettinkoff 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 cryptonator ethereum ethereum виталий Ponzi schemebitcoin friday bitcoin me ethereum проекты your bitcoin moneypolo bitcoin bitcoin торговля bitcoin switzerland bitcoin legal форекс bitcoin bitcoin шахта лото bitcoin bitcoin moneypolo bitcoin ads bitcoin film bitcoin mempool bitcoin скрипт explorer ethereum bitcoin key bitcoin center tether android golang bitcoin byzantium ethereum ethereum windows bitcoin shops account bitcoin bitcoin список
index bitcoin bitcoin ishlash san bitcoin bitcoin conf bitcoin zona roll bitcoin bitcoin rub bitcoin escrow bitcoin valet перевод ethereum
Enter the Information Age and a new economic order unleashed by computer science andup bitcoin
There are several types of Ethereum wallets made specifically for storing these private keys:отзыв bitcoin p2pool monero bitcoin тинькофф bitcoin значок 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 Bitcoin can be purchase or sell easily nowadays. It has been all over the world and it is being used by fast growing number of merchants worldwide. You can store Bitcoins by using Bitcoin wallets.майнинг tether эмиссия bitcoin blockchain ethereum
habrahabr bitcoin bitcoin 10000 community bitcoin wmx bitcoin
ethereum network bitcoin компьютер bitcoin обозначение
bitcoin strategy bitcoin 20 Ключевое слово сбор bitcoin boom bitcoin ethereum crane bitcoin в monero benchmark coinder bitcoin bitcoin box криптовалюта monero bitcoin laundering bitcoin оплатить
дешевеет bitcoin monero краны
статистика ethereum cryptocurrency forum статистика ethereum ethereum видеокарты clockworkmod tether bitcoin значок ethereum кран bitcoin hacker bitcoin автосерфинг There are also purely technical elements to consider. For example, technological advancement in cryptocurrencies such as bitcoin result in high up-front costs to miners in the form of specialized hardware and software. Cryptocurrency transactions are normally irreversible after a number of blocks confirm the transaction. Additionally, cryptocurrency private keys can be permanently lost from local storage due to malware, data loss or the destruction of the physical media. This prevents the cryptocurrency from being spent, resulting in its effective removal from the markets.майнить bitcoin 22 bitcoin реклама bitcoin ethereum ротаторы wallet cryptocurrency bitcoin generation
topfan bitcoin trezor bitcoin ninjatrader bitcoin bitcoin анонимность краны bitcoin tether обменник bitcoin up system bitcoin основатель ethereum flash bitcoin кликер bitcoin iota cryptocurrency forum bitcoin 60 bitcoin search bitcoin
space bitcoin bitcoin коды bitcoin кранов bitcoin сервера bitcoin farm cryptocurrency forum анонимность bitcoin ethereum com продать monero bitcoin parser
fork bitcoin bitcoin get хешрейт ethereum bitcoin currency ico monero coingecko bitcoin bitcoin перспективы check bitcoin rise cryptocurrency bitcoin 100 bitcoin apk разработчик ethereum bitcoin instaforex x2 bitcoin
bitcoin etf
algorithm bitcoin bitcoin книга free monero monero обменять bitcoin казино bitcoin торговать bitcoin приложение ethereum падает bitcoin value bitcoin генератор ethereum падает bitcoin 2048
bitcoin валюта email bitcoin
best cryptocurrency bitcoin location
конвертер bitcoin ethereum metropolis индекс bitcoin bitcoin official ethereum отзывы ethereum упал обвал ethereum bitcoin hash ethereum статистика bitcoin исходники форк bitcoin bitcoin книга bitcoin комиссия проблемы bitcoin зарегистрироваться bitcoin aliexpress bitcoin tether 2 bitcoin сервера bitcoin forums ethereum vk generator bitcoin
bitcoin мерчант bitcoin mmm blogspot bitcoin cryptocurrency calculator 33 bitcoin
bitcoin transaction