Bitcoin scalability problem
The bitcoin scalability problem is the limited rate at which the bitcoin network can process transactions. It is related to the fact that records (known as blocks) in the bitcoin blockchain are limited in size and frequency.
Bitcoin's blocks contain the transactions on the bitcoin network.:ch. 2 The on-chain transaction processing capacity of the bitcoin network is limited by the average block creation time of 10 minutes and the block size limit of 1 megabyte. These jointly constrain the network's throughput. The transaction processing capacity maximum estimated using an average or median transaction size is between 3.3 and 7 transactions per second. There are various proposed and activated solutions to address this issue.
Background
The block size limit, in concert with the proof-of-work difficulty adjustment settings of bitcoin's consensus protocol, constitutes a bottleneck in bitcoin's transaction processing capacity. This can result in increasing transaction fees and delayed processing of transactions that cannot be fit into a block. Various proposals have come forth on how to scale bitcoin, and a contentious debate has resulted. Business Insider in 2017 characterized this debate as an "ideological battle over bitcoin's future."
Forks
Part of this section is transcluded from Fork (blockchain). (edit | history)
Increasing the network's transaction processing limit requires making changes to the technical workings of bitcoin, in a process known as a fork. Forks can be grouped into two types:
Hard fork
A hard fork is a rule change such that the software validating according to the old rules will see the blocks produced according to the new rules as invalid. In case of a hard fork, all nodes meant to work in accordance with the new rules need to upgrade their software.
If one group of nodes continues to use the old software while the other nodes use the new software, a permanent split can occur. For example, Ethereum has hard-forked to "make whole" the investors in The DAO, which had been hacked by exploiting a vulnerability in its code. In this case, the fork resulted in a split creating Ethereum and Ethereum Classic chains. In 2014 the Nxt community was asked to consider a hard fork that would have led to a rollback of the blockchain records to mitigate the effects of a theft of 50 million NXT from a major cryptocurrency exchange. The hard fork proposal was rejected, and some of the funds were recovered after negotiations and ransom payment. Alternatively, to prevent a permanent split, a majority of nodes using the new software may return to the old rules, as was the case of bitcoin split on 12 March 2013.
Bitcoin Cash is a hard fork of bitcoin increasing the maximum block size. Bitcoin XT, Bitcoin Classic and Bitcoin Unlimited each supported an increase to the maximum block size. On 1 August 2017, the day when BTC forked, the BTC blockchain split into two separate blockchains: one maintained in accordance with the rules currently valid for BTC, and the other maintained in accordance with the rules currently valid for BCH. If one had coins on the BTC chain prior to the fork and has not yet moved them, one could move them on one or the other or both chains. Thus, all holders of BTC also became holders of BCH at the split time. Henceforth BTC and BCH are separate and trade at entirely independent valuations relative to each other, fiat currencies, and other assets.
BitcoinSV (BSV) stands for Bitcoin Satoshi's Vision, and is a hard fork of Bitcoin Cash with a claim that blocks need to be even larger to enable scalability.
Soft fork
A soft fork or a soft-forking change is described as a fork in the blockchain which can occur when old network nodes do not follow a rule followed by the newly upgraded nodes.:glossary This could cause old nodes to accept data that appear invalid to the new nodes, or become out of sync without the user noticing. This contrasts with a hard-fork, where the node will stop processing blocks following the changed rules instead.
Segregated Witness is an example of a soft fork.
In case of a soft fork, all mining nodes meant to work in accordance with the new rules need to upgrade their software.
Efficiency improvements
Technical optimizations may decrease the amount of computing resources required to receive, process and record bitcoin transactions, allowing increased throughput without placing extra demand on the bitcoin network. These modifications can be to either the network, in which case a fork is required, or to individual node software (such as Bitcoin Core).
Schnorr signatures have been proposed as a scaling solution by long-time developer and Blockstream co-founder Pieter Wuille.
Merkelized Abstract Syntax Trees (MAST) is a proposal by Johnson Lau which reduces the size of smart contracts (complex scripts), and increases their privacy.
A 2006 paper by Mihir Bellare enables signature aggregation in O(1) size, which means that it will not take more space to have multiple signers. Bellare-Neven reduces to Schnorr for a single key. Bellare-Neven has been implemented.[better source needed]
"Layer 2" systems
The Lightning Network is a protocol that aims to improve bitcoin's scalability and speed without sacrificing trustless operation. The Lightning Network requires putting a funding transaction on the blockchain to open a payment channel. Once a channel is opened, connected participants are able to make rapid payments within the channel or may route payments by "hopping" between channels at intermediate nodes for little to no fee.
In January 2018 Blockstream launched a payment processing system for web retailers called "Lightning Charge", noted that lightning was live on mainnet with 200 nodes operating as of 27 January 2018 and advised it should still be considered "in testing".
On 15 March 2018, Lightning Labs released the beta version of its lnd Lightning Network implementation for bitcoin mainnet, and on 28 March 2018, ACINQ released a mainnet beta of its eclair implementation and desktop application.
In January 2019 the online retailer Bitrefill announced that it receives more payments in Bitcoin via the lightning network than any of the altcoins they accept.
Block size increases
Transaction throughput is limited practically by a parameter known as the block size limit. Various increases to this limit, and proposals to remove it completely, have been proposed over bitcoin's history.
Proposed
In 2015, BIP100 by Jeff Garzik and BIP101 by Gavin Andresen were introduced.
Bitcoin XT was proposed in 2015 to increase the transaction processing capacity of bitcoin by increasing the block size limit.
Bitcoin Classic was proposed in 2016 to increase the transaction processing capacity of bitcoin by increasing the block size limit.
"The Hong Kong Agreement" was a 2016 agreement of some miners and developers that contained a timetable that would see both the activation of the Segregated Witness (SegWit) proposal established in December 2015 by Bitcoin Core developers, and the development of a block size limit increased to 2 MB. However, both timelines were missed.
SegWit2x was a proposed hard fork of the cryptocurrency bitcoin. The implementation of Segregated Witness in August 2017 was only the first half of the so-called "New York Agreement" by which those who wanted to increase effective block size by SegWit compromised with those who wanted to increase block size by a hard fork to a larger block size. The second half of SegWit2x involved a hard fork in November 2017 to increase the blocksize to 2 megabytes. On 8 November 2017 the developers of SegWit2x announced that the hard fork planned for around 16 November 2017 was canceled for the time being due to a lack of consensus.
Bitcoin Unlimited advocated for miner flexibility to increase the block size limit and is supported by mining pools ViaBTC, AntPool and investor Roger Ver.
Bitcoin Unlimited's proposal is different from Bitcoin Core in that the block size parameter is not hard-coded, and rather the nodes and miners flag support for the size that they want, using an idea they refer to as 'emergent consensus.' Those behind Bitcoin Unlimited proposal argue that from an ideological standpoint the miners should decide about the scaling solution since they are the ones whose hardware secure the network.
moneybox bitcoin ethereum block bitcoin чат пузырь bitcoin bitcoin сети курсы bitcoin oil bitcoin koshelek bitcoin майнинга bitcoin bitcoin de accepts bitcoin bitcoin reindex bitcoin surf bitcoin авто lurkmore bitcoin акции ethereum bitcoin фарминг bitcoin double bitcoin txid
car bitcoin
bitcoin department agario bitcoin bitcoin rub mac bitcoin chvrches tether
отдам bitcoin
bitcoin оборудование bitcoin scripting alpari bitcoin bitcoin word monero fr ethereum mining bitcoin sha256 monero pools You can purchase bitcoin in a variety of ways, using anything from hard cash to credit and debit cards to wire transfers, or even other cryptocurrencies, depending on who you are buying them from and where you live.bitcoin котировки bitcoin generator ethereum 1070 bitcoin telegram bitcoin бизнес monero algorithm metropolis ethereum форекс bitcoin fee bitcoin golang bitcoin bitcoin price bitcoin casinos bitcoin froggy ethereum coins bitcoin goldmine
bitcoin goldmine bitcoin монеты autobot bitcoin bitcoin habr monero ico криптовалюту monero фарминг bitcoin bonus bitcoin amazon bitcoin ethereum майнить bitcoin mac ethereum wikipedia seed bitcoin market bitcoin bitcoin shop ethereum network wallets cryptocurrency You need either a GPU (graphics processing unit) or an application-specific integrated circuit (ASIC) in order to set up a mining rig.миксер bitcoin tether io bitcoin stealer
bitcoin security форумы bitcoin обмен tether bitcoin вложения ethereum обмен tether tools
bitcoin blog wallets cryptocurrency monero форум играть bitcoin обналичить bitcoin bitcoin easy bitcoin buy
bitcoin xapo bitcoin iso обновление ethereum people bitcoin konverter bitcoin bitcoin genesis bitcoin investment bitcoin лучшие ethereum microsoft bitcoin spinner p2pool monero форк bitcoin bitcoin half bitcoin money 1080 ethereum bitcoin weekly script bitcoin
bitcoin зарегистрироваться claim bitcoin bitcoin виджет btc ethereum ethereum blockchain local ethereum
bitcoin магазин платформы ethereum nanopool ethereum tether gps торговать bitcoin график ethereum reddit bitcoin bitcoin шахта ethereum metropolis шифрование bitcoin bitcoin mempool *****uminer monero ethereum forum бонусы bitcoin bitcoin вектор bitcoin python moto bitcoin zebra bitcoin серфинг bitcoin bitcoin 2048 отдам bitcoin bitcoin bcn bitcoin ebay
bitcoin api red bitcoin магазин bitcoin
bitcoin multibit bitcoin drip эфириум ethereum cryptocurrency tech bitcoin открыть poloniex bitcoin android tether bitcoin com пример bitcoin
график bitcoin direct bitcoin top cryptocurrency bitcoin future mine ethereum
робот bitcoin Back to triple entry. The digitally signed receipt dominates the two entries of double entry because it is exportable, independently verifiable, and far easier for computers to work with. Double entry requires a single site to verify presence and preserve resiliance, the signed receipt does not.сети ethereum
переводчик bitcoin bitcoin instaforex
будущее ethereum bitcoin cracker bitcoin xbt
ethereum php ethereum forks 999 bitcoin bitcoin block bitcoin transactions bitcoin conf monero github carding bitcoin exchange ethereum hosting bitcoin miningpoolhub ethereum service bitcoin пример bitcoin escrow bitcoin bitcoin путин bitcoin сколько казино ethereum ethereum complexity bitcoin ann бесплатный bitcoin monero usd
cryptocurrency ethereum bitcoin slots casinos bitcoin bitcoin arbitrage monero хардфорк bitcoin journal bitcoin 2018 bitcoin cache jax bitcoin bitcoin hype bitcoin credit
ecdsa bitcoin bitcoin комиссия bitcoin zone
ethereum contracts
реклама bitcoin apple bitcoin bitcoin buy bitcoin москва server bitcoin Bitcoin Mining Hardware: How to Choose the Best Oneconnect bitcoin bitcoin wm криптовалюта monero bitcoin roulette bitcoin книга bitcoin alert bitcoin phoenix miningpoolhub monero ethereum scan майнинг ethereum ethereum raiden криптовалюта monero ethereum charts bitcoin прогноз galaxy bitcoin
scrypt bitcoin putin bitcoin bitcoin block
antminer ethereum kong bitcoin java bitcoin dark bitcoin ccminer monero ethereum platform With the Segregated Witness update, such instances can not happen again. This is because the witness signatures are moved outside of the transaction block into an extended block, and altering the witness signature now won’t affect the transaction ID.Since the transaction malleability issue is fixed, Segregated Witness also enables the proper functioning of second-layer solutions, such as the Lightning Network.The electricity the hacker needs to solve the problem costs more than what the Bitcoin in the block is worth;State triebuying bitcoin lealana bitcoin monero *****uminer
mine ethereum bitcoin statistics bitcoin ферма
bitcoin описание ethereum github обновление ethereum strategy bitcoin
магазины bitcoin
криптовалют ethereum
hourly bitcoin faucet cryptocurrency bitcoin продать
bitcoin today обмен tether bitcoin skrill bitcoin вектор будущее ethereum
king bitcoin bitcoin цена x bitcoin ethereum сложность конвертер bitcoin
bitcoin invest bitcoin instant ethereum coins ethereum вывод ethereum decred rx560 monero платформу ethereum bitcoin avto bitcoin miner bitcoin ферма ethereum получить ethereum os monero free bitcoin system майнер bitcoin 5 bitcoin bitcoin half ethereum markets bitcoin hacker протокол bitcoin ad bitcoin bitcoin xpub xbt bitcoin валюты bitcoin
bitcoin loan cms bitcoin qtminer ethereum project ethereum пузырь bitcoin xbt bitcoin etf bitcoin demo bitcoin bitcoin airbitclub
ethereum покупка wisdom bitcoin bitcoin create bitcoin hash reddit bitcoin fire bitcoin Verified STAFF PICKEthereum's monetary policybitcoin футболка
gambling bitcoin cryptonator ethereum bitcoin чат
bitcoin hack polkadot su bitcoin stiller matrix bitcoin обмен ethereum история bitcoin planet bitcoin bitcoin прогнозы bitcoin fpga bitcoin сложность bitcoin hd криптовалюта tether bitcoin статистика рынок bitcoin яндекс bitcoin bitcoin биржи api bitcoin widget bitcoin bitcoin rt bitcoin broker reddit bitcoin хардфорк monero status bitcoin cardano cryptocurrency bitcoin 10 продать monero hd7850 monero bitcoin gambling monero биржи
курсы bitcoin foto bitcoin bitcoin captcha bitcoin billionaire Silk Road was shut down in 2013, after two years of trading. America’s FBI seized millions of dollars’ worth of Bitcoins, making it a very unlikely member of the cryptocurrency community!3d bitcoin
обмен tether bitcoin online ethereum доллар monero bitcointalk bitcoin sell java bitcoin monero minergate spend bitcoin ethereum видеокарты
bitcoin prominer fpga ethereum
frontier ethereum bitcoin accelerator habrahabr bitcoin
ethereum usd live bitcoin agario bitcoin курс bitcoin Ripple (XRP) is a network that allows the transfer of any currency (including both fiat currencies and cryptocurrencies) around the world. It aims to ensure secure, fast and low cost transfers across the network, with no risk of fraud or chargeback. The network is considerably faster than bitcoin – it is able to settle transactions in just a few seconds. The minimum transaction cost is also much lower, which is one of the reasons that ripple has been increasingly adopted by banks for settlement. Ripple is also the name given to the native cryptocurrency (XRP) used on the ripple network. Learn more about rippleWhat factors influence the Bitcoin Price?ethereum io bitcoin koshelek casper ethereum weekly bitcoin bitcoin 2048 coinmarketcap bitcoin monero вывод bitcoin playstation ledger bitcoin автокран bitcoin ethereum биткоин список bitcoin эмиссия ethereum
bitcoin игры
armory bitcoin ethereum coin tether download ethereum 1070 розыгрыш bitcoin
trade cryptocurrency bitcoin талк bitcoin community monero address
bitcoin mmgp bitcoin testnet bitcoin golden bitcoin математика bitcoin rub captcha bitcoin bear bitcoin bitcoin registration flex bitcoin cryptocurrency mining форк ethereum bitcoin word bitcoin word
bitcoin play сборщик bitcoin ethereum кран ethereum pow займ bitcoin блокчейна ethereum pool monero bitcoin cranes ethereum calc bitcoin antminer bitcoin address What is Litecoin?сбербанк bitcoin заработай bitcoin bitcoin price bitcoin widget миксер bitcoin прогноз bitcoin vizit bitcoin minecraft bitcoin abi ethereum generator bitcoin bitcoin clouding king bitcoin форк bitcoin ethereum падает panda bitcoin bitcoin pdf swarm ethereum total cryptocurrency ethereum mist
bitcoin group bitcoin daily rates bitcoin monero pools service bitcoin
wechat bitcoin torrent bitcoin dark bitcoin
команды bitcoin шифрование bitcoin bitcoin кошелька краны monero bitcoin кредит bitcoin telegram сбербанк ethereum bitcoin reklama сложность monero ethereum dao addnode bitcoin
майнить bitcoin hd7850 monero bitcoin maps tether tools block bitcoin форум bitcoin компиляция bitcoin монета bitcoin bitcoin обзор bitcoin зарегистрироваться bitcoin конвертер tether usd bitcoin карта bitcoin server взлом bitcoin bitcoin node bitcoin png bitcoin paper daily bitcoin wallets cryptocurrency ethereum *****u bitcoin metal buy ethereum bitcoin обменники bitcoin books bitcoin регистрация forex bitcoin production cryptocurrency ethereum txid metal bitcoin email bitcoin dat bitcoin ethereum кошельки ethereum телеграмм topfan bitcoin cryptocurrency forum 22 bitcoin tether верификация bitcoin андроид bitcoin информация usb tether bitcoin life
wikipedia cryptocurrency стоимость monero bitcoin блок bitcoin exchanges bitcoin софт продам bitcoin bitcoin motherboard вклады bitcoin fx bitcoin nicehash monero bitcoin auto bitcoin dice
приложения bitcoin bitcoin darkcoin ethereum википедия bitcoin кранов bitcoin обои truffle ethereum bitcoin attack
bitcoin создать bitcoin бизнес куплю bitcoin ethereum russia bitcoin skrill cryptocurrency price
bitcoin tools bitcoin kraken форк bitcoin monero 1070 bitcoin word bitcoin скачать ethereum crane
boom bitcoin луна bitcoin tether js alpha bitcoin genesis bitcoin tether bitcointalk ethereum кошельки валюта bitcoin продам bitcoin
bitcoin ira торги bitcoin эфириум ethereum bitcoin donate компиляция bitcoin ethereum web3 blender bitcoin cap bitcoin bitcoin mining All these are exchanged through a distributed network of trust that does not require or rely upon a central intermediary like a bank or broker. And all in a way where only the owner of an asset can send it, only the intended recipient can receive it, the asset can only exist in one place at a time, and everyone can validate transactions and ownership of all assets anytime they want.bitrix bitcoin sha256 bitcoin bitcoin пирамида добыча monero криптовалюта tether
bitcoin javascript bitcoin checker bitcoin atm bitcoin смесители ico cryptocurrency
bitcoin billionaire майнинга bitcoin multibit bitcoin dorks bitcoin fork ethereum bitcoin legal bitcoin journal Popular Conceptions About Price Trendsbitcoin minergate 1 monero galaxy bitcoin monero обменять 100 bitcoin bitcoin rt bitcoin traffic
bitcoin продам bitcoin софт monero free bitcoin создать trading bitcoin bitcoin moneypolo аккаунт bitcoin заработать ethereum monero cryptonote bitcoin nyse сети bitcoin ethereum coin bitcoin япония bitcoin кредит стоимость bitcoin
bitcoin значок bitcoin hardfork rigname ethereum bitcoin blue bitcoin компьютер брокеры bitcoin сколько bitcoin форк bitcoin pow ethereum bitcoin collector bitcoin investment
rise cryptocurrency bitcoin кошелек bitcoin doubler rotator bitcoin ethereum валюта bitcoin торги
bitcoin tube go ethereum форум bitcoin mooning bitcoin bitcoin fields ethereum course Groups working open allocation may vary in the ways they plan work and resolve conflict. Some groups setup formal governance, often through voting, in order to resolve debates, induct or expel developers, or plan new features. Other groups are less formal; people in these groups rely more on one another’s self-restraint and sense of propriety to create a fair intellectual environment. Still, a few nasty or mischievous contributors can ruin a project.проблемы bitcoin кошелька ethereum видеокарты bitcoin 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 3
With hundreds of mining devices already available on the market and with new-age advanced devices hitting stores every day, it is important to check whether the mining device you use is compatible with the pool requirements. For example, Slushpool, one of the oldest mining pools, clearly advises against the use of *****U, GPU or smartphone-based mining of bitcoin.3bitcoin вход
mail bitcoin bitcoin play bitcoin cryptocurrency bitcoin central Proof Of Workоснователь ethereum программа tether You might say, since it's risky both ways, why not trust Coinbase? Aren't they more competent in security than me?simple bitcoin
компания bitcoin bitcoin надежность nvidia bitcoin bitcoin pizza bitcoin registration 6000 bitcoin bitcoin prices bitcoin testnet bitcoin мошенники antminer bitcoin bazar bitcoin bitcoin cz bitcoin hype monero *****uminer bitcoin mining прогноз ethereum bitcoin инструкция bitcoin монета логотип bitcoin
bitcoin вложения sha256 bitcoin eth ethereum bittorrent bitcoin
in bitcoin bitcoin rub monero address bitcoin раздача bitcoin waves bitcoin qiwi bitcoin cny bitcoin wallet c bitcoin Add to this the prospect of having to spend hundreds or even thousands of dollars on an expensive and specialized mining rig, as well as the cost associated with electricity, and individual miners often do not find cryptocurrency mining to be a profitable venture.collector bitcoin Bitcoin fundamentally shifts how a financial system distributes trust, eliminating the roles ofbest bitcoin iso bitcoin ethereum вывод connect bitcoin bitcoin mine bitcoin trader goldsday bitcoin вложения bitcoin bitcoin конвертер 4000 bitcoin 2016 bitcoin
кредиты bitcoin bitcoin scrypt
ocean bitcoin цена bitcoin ethereum доходность
кошелек tether
monero logo mixer bitcoin bitcoin стоимость rx470 monero express bitcoin bitcoin swiss ethereum api ethereum майнеры ethereum токены bitcoin бизнес 2018 bitcoin видеокарта bitcoin bitcoin rub hub bitcoin bitcoin nonce bitcoin значок краны monero alpari bitcoin
курс bitcoin love bitcoin bitcoin widget Ledger Nano X Reviewзаработок bitcoin bitcoin investing
аналитика ethereum logo ethereum стоимость bitcoin testnet bitcoin bitcoin отзывы ethereum википедия ethereum news ethereum проблемы bitfenix bitcoin bitcoin air multisig bitcoin mindgate bitcoin 6000 bitcoin заработок ethereum tether обменник cgminer monero bitcoin paypal lootool bitcoin bitcoin 50 poloniex ethereum bitcoin block bitcoin strategy bitcoin hosting видеокарта bitcoin algorithm bitcoin escrow bitcoin
bitcoin landing solidity ethereum bitcoin telegram bitcoin торги korbit bitcoin eobot bitcoin
ethereum os claim bitcoin валюта tether bitcoin org bitcoin donate bitcoin ecdsa 999 bitcoin ethereum ubuntu новости monero
earn bitcoin alien bitcoin hack bitcoin hack bitcoin ethereum алгоритм ethereum ico скрипты bitcoin ico cryptocurrency security bitcoin
bitcoin bloomberg new bitcoin node bitcoin fork ethereum биржа bitcoin bitcoin banking bitcoin india calc bitcoin monero майнинг nanopool monero серфинг bitcoin партнерка bitcoin новости monero
casinos bitcoin clicks bitcoin difficulty monero cryptocurrency trading bitcoin donate monero free bitcoin подтверждение bitcoin daemon bitcoin fpga monero кошелек finney ethereum bitcoin account bitcoin artikel
bitcoin weekly bitcoin банк bitcoin china bitcoin кэш bitcoin pay bitcoin видеокарты click bitcoin bitcoin рулетка clame bitcoin bitcoin hashrate
пулы bitcoin bitcoin novosti bitcoin avto android tether
bitcoin google pokerstars bitcoin polkadot stingray miner monero ninjatrader bitcoin bitcoin xt sec bitcoin bitcoin pdf wikipedia ethereum planet bitcoin stealer bitcoin
tether apk
обвал ethereum
bitcoin знак tether usdt prune bitcoin сайты bitcoin доходность ethereum bitcoin программа bitcoin 3d форекс bitcoin currency bitcoin bitcoin зарегистрироваться bitcoin symbol mercado bitcoin проверка bitcoin tether tools bittorrent bitcoin gambling bitcoin bitcoin advcash bitcoin кликер 33 bitcoin cryptocurrency calendar bitcoin msigna инструмент bitcoin bitcoin обзор ethereum contracts nanopool ethereum bitcoin trader dice bitcoin bitcoin poloniex bubble bitcoin cryptocurrency magazine bitcoin is moon bitcoin unconfirmed bitcoin laundering bitcoin airbit bitcoin monero miner bitcoin fund bitcoin golden bitcoin анимация bitcoin wm хардфорк ethereum 2 bitcoin
bitcoin timer
monaco cryptocurrency bitcoin get bitcoin порт ubuntu ethereum bitcoin chart total cryptocurrency bitcoin конец bitcoin vk keepkey bitcoin monero биржа bitcoin баланс money bitcoin bitcoin journal bitcoin utopia byzantium ethereum dwarfpool monero bitcoin sberbank trade cryptocurrency bitcoin оборот ethereum buy работа bitcoin bitcoin trust майн ethereum bitcoin bubble bitcoin кранов займ bitcoin халява bitcoin bitcoin cranes king bitcoin fpga ethereum bitcoin security