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src: ethereum.org

Ethereum is an open-source, public, blockchain-based distributed computing platform and operating system featuring smart contract (scripting) functionality. It supports a modified version of Nakamoto consensus via transaction based state transitions.

Ether is a cryptocurrency whose blockchain is generated by the Ethereum platform. Ether can be transferred between accounts and used to compensate participant mining nodes for computations performed. Ethereum provides a decentralized Turing-complete virtual machine, the Ethereum Virtual Machine (EVM), which can execute scripts using an international network of public nodes. "Gas", an internal transaction pricing mechanism, is used to mitigate spam and allocate resources on the network.

Ethereum was proposed in late 2013 by Vitalik Buterin, a cryptocurrency researcher and programmer. Development was funded by an online crowdsale that took place between July and August 2014. The system went live on 30 July 2015, with 11.9 million coins "premined" for the crowdsale. This accounts for about 13 percent of the total circulating supply.

In 2016, as a result of the collapse of The DAO project, Ethereum was split into two separate blockchains - the new separate version became Ethereum (ETH), and the original continued as Ethereum Classic (ETC). The value of the Ethereum currency grew over 13,000 percent in 2017.


Video Ethereum



Etymology

Vitalik Buterin picked the name Ethereum after browsing Wikipedia articles about elements and science fiction, when he found the name, noting, "I immediately realized that I liked it better than all of the other alternatives that I had seen; I suppose it was the fact that sounded nice and it had the word 'ether', referring to the hypothetical invisible medium that permeates the universe and allows light to travel."


Maps Ethereum



History

Ethereum was initially described in a white paper by Vitalik Buterin, a programmer involved with Bitcoin Magazine, in late 2013 with a goal of building decentralized applications. Buterin had argued that Bitcoin needed a scripting language for application development. Failing to gain agreement, he proposed development of a new platform with a more general scripting language.

At the time of public announcement in January 2014, the core Ethereum team was Vitalik Buterin, Mihai Alisie, Anthony Di Iorio, and Charles Hoskinson. Formal development of the Ethereum software project began in early 2014 through a Swiss company, Ethereum Switzerland GmbH (EthSuisse). Subsequently, a Swiss non-profit foundation, the Ethereum Foundation (Stiftung Ethereum), was created as well. Development was funded by an online public crowdsale during July-August 2014, with the participants buying the Ethereum value token (ether) with another digital currency, bitcoin. While there was early praise for the technical innovations of Ethereum, questions were also raised about its security and scalability.

Enterprise Ethereum Alliance (EEA)

In March 2017, various blockchain start-ups, research groups, and Fortune 500 companies announced the creation of the Enterprise Ethereum Alliance (EEA) with 30 founding members. By May, the nonprofit organization had 116 enterprise members--including ConsenSys, CME Group, Cornell University's research group, Toyota Research Institute, Samsung SDS, Microsoft, Intel, J. P. Morgan, Cooley LLP, Merck KGaA, DTCC, Deloitte, Accenture, Banco Santander, BNY Mellon, ING, and National Bank of Canada. By July 2017, there were over 150 members in the alliance, including recent additions MasterCard, Cisco Systems, and Scotiabank.

Milestones

Several codenamed prototypes of the Ethereum platform were developed by the Foundation, as part of their Proof-of-Concept series, prior to the official launch of the Frontier network. "Olympic" was the last of these prototypes, and public beta pre-release. The Olympic network provided users with a bug bounty of 25,000 ether for stress testing the limits of the Ethereum blockchain. "Frontier" marked the tentative experimental release of the Ethereum platform in July 2015.

"Homestead" was the first to be considered stable. It includes improvements to transaction processing, gas pricing, and security. Since the initial launch, Ethereum has undergone several planned protocol upgrades, which are important changes affecting the underlying functionality and/or incentive structures of the platform.

"Metropolis Part 1: Byzantium" was launched on October 16, 2017, and included changes to reduce the complexity of the EVM and provide more flexibility for smart contract developers. Byzantium also adds supports for zk-SNARKs (from Zcash); with the first zk-SNARK transaction occurring on testnet on September 19, 2017.

There are at least two other protocol upgrades planned in the future: "Metropolis Part 2: Constantinople" will lay the foundations for the transition to proof-of-stake (Casper), make adjustments to the difficulty time bomb, and add support for account abstraction.

The DAO event

In 2016 a decentralized autonomous organization called The DAO, a set of smart contracts developed on the platform, raised a record US$150 million in a crowdsale to fund the project. The DAO was exploited in June when US$50 million in ether were claimed by an anonymous entity. The event sparked a debate in the crypto-community about whether Ethereum should perform a contentious "hard fork" to reappropriate the affected funds. As a result of the dispute, the network split in two. Ethereum (the subject of this article) continued on the forked blockchain, while Ethereum Classic continued on the original blockchain. The hard fork created a rivalry between the two networks.

After the hard fork related to The DAO, Ethereum subsequently forked twice in the fourth quarter of 2016 to deal with other attacks. By the end of November 2016, Ethereum had increased its DDoS protection, de-bloated the blockchain, and thwarted further spam attacks by hackers.


Ethereum In The Crosshairs Of Regulators | PYMNTS.com
src: securecdn.pymnts.com


Ether

Ether is a fundamental cryptocurrency for operation of Ethereum, which thereby provides a public distributed ledger for transactions. It is used to pay for gas, a unit of computation used in transactions and other state transitions. Mistakingly, this currency is also referred to as Ethereum. It is listed under the code ETH and traded on cryptocurrency exchanges, and the Greek uppercase Xi character (?) is generally used for its currency symbol. It is also used to pay for transaction fees and computational services on the Ethereum network.

Characteristics

As with other cryptocurrencies, the validity of each ether is provided by a blockchain, which is a continuously growing list of records, called blocks, which are linked and secured using cryptography. By design, the blockchain is inherently resistant to modification of the data. It is an open, distributed ledger that records transactions between two parties efficiently and in a verifiable and permanent way. Unlike Bitcoin, Ethereum operates using accounts and balances in a manner called state transitions. This does not rely upon unspent transaction outputs (UTXOs). State denotes the current balances of all accounts and extra data. State is not stored on the blockchain, it is stored in a separate Merkle Patricia tree. A cryptocurrency wallet stores the public and private "keys" or "addresses" which can be used to receive or spend Ether. These can be generated through BIP 39 style mnemonics for a BIP 32 "HD Wallet". In Ethereum, this is unnecessary as it does not operate in a UTXO scheme. With the private key, it is possible to write in the blockchain, effectively making an ether transaction. To send ether to an account, you need the public key of that account. Ether accounts are pseudonymous in that they are not linked to individual persons, but rather to one or more specific addresses. Owners can store these addresses in software, on paper and possibly in memory ("brain wallet").

Addresses

Ethereum addresses are composed of the prefix "0x", a common identifier for hexadecimal, concatenated with the rightmost 20 bytes of the Keccak-256 hash (big endian) of the ECDSA public key. In hexadecimal, 2 digits represents a byte, meaning addresses contain 40 hexadecimal digits. One example is 0xb794F5eA0ba39494cE839613fffBA74279579268, the Poloniex ColdWallet. Contract addresses are in the same format, however they are determined by sender and creation transaction nonce. User accounts are indistinguishable from contract accounts given only an address for each and no blockchain data. Any valid Keccak-256 hash put into the described format is valid, even if it does not correspond to an account with a private key or a contract. This is unlike Bitcoin, which uses base58check to ensure that addresses are properly typed.

Comparison to bitcoin

Ether is different from Bitcoin (the cryptocurrency with the largest market capitalization as of January 2018) in several aspects:

  • Its block time is 14 to 15 seconds, compared with 10 minutes for bitcoin.
  • Mining of ether generates new coins at a usually consistent rate, occasionally changing during hard forks, while for bitcoin the rate halves every 4 years.
  • For proof-of-work, it uses the Ethash algorithm which reduces the advantage of specialized ASICs in mining.
  • Transaction fees differ by computational complexity, bandwidth use and storage needs (in a system known as gas), while bitcoin transactions compete by means of transaction size, in bytes.
  • Ethereum gas units each have a price that can be specified in a transaction. This is typically measured in Gwei. Bitcoin transactions usually have fees specified in satoshis per byte.
  • Transaction fees are generally considerably lower for ether than for Bitcoin. In December 2017, the median transaction fee for ether corresponded to $0.33, while for bitcoin it corresponded to $23.
  • Ethereum uses an account system where values in Wei are debited from accounts and credited to another, as opposed to Bitcoin's UTXO system, which is more analogous to spending cash and receiving change in return. Both systems have their pros and cons; in terms of storage space, complexity, and security/anonymity.

Supply

The total supply of ether was ?98 million as of January 2018. In 2017, mining generated 9.2 million new ether, corresponding to a 10% increase in its total supply. Casper FFG and CBC are expected to reduce the inflation rate to between 0.5% to 2%. There is no currently implemented hard cap on the total supply of ETH, but it is expected to end at a certain point, and become deflationary.

Markets and stores

Ether can be traded by regular currency brokers, cryptocurrency exchanges, as well as many online cryptocurrency wallets. As of January 2018, at least 150 stores accept ether.


How to Buy Ethereum (Ether): 2018 Guide to Investing รข€
src: ethereumprice.org


Platform

Virtual Machine

The Ethereum Virtual Machine (EVM) is the runtime environment for smart contracts in Ethereum. It is a 256-bit register stack, designed to run the same code exactly as intended. It is the fundamental consensus mechanism for Ethereum. The formal definition of the EVM is specified in the Ethereum Yellow Paper. It is sandboxed and also completely isolated from the network, filesystem or other processes of the host computer system. Every Ethereum node in the network runs an EVM implementation and executes the same instructions. In February 1, 2018, there were 27,500 nodes in the main Ethereum network. Ethereum Virtual Machines have been implemented in C++, Go, Haskell, Java, JavaScript, Python, Ruby, Rust, and WebAssembly (currently under development).

Smart contracts

Ethereum's smart contracts are based on different computer languages, which developers use to program their own functionalities. Smart contracts are high-level programming abstractions that are compiled down to EVM bytecode and deployed to the Ethereum blockchain for execution. They can be written in Solidity (a language library with similarities to C and JavaScript), Serpent (similar to Python, but deprecated), LLL (a low-level Lisp-like language), and Mutan (Go-based, but deprecated). There is also a research-oriented language under development called Viper (a strongly-typed Python-derived decidable language).

Smart contracts can be public, which opens up the possibility to prove functionality, e.g. self-contained provably fair casinos.

One issue related to using smart contracts on a public blockchain is that bugs, including security holes, are visible to all but cannot be fixed quickly. One example of this is the 17 June 2016 attack on The DAO, which could not be quickly stopped or reversed.

There is ongoing research on how to use formal verification to express and prove non-trivial properties. A Microsoft Research report noted that writing solid smart contracts can be extremely difficult in practice, using The DAO hack to illustrate this problem. The report discussed tools that Microsoft had developed for verifying contracts, and noted that a large-scale analysis of published contracts is likely to uncover widespread vulnerabilities. The report also stated that it is possible to verify the equivalence of a Solidity program and the EVM code.

Applications

Ethereum blockchain applications are usually referred to as DApps (decentralized application), since they are based on the decentralized Ethereum Virtual Machine, and its smart contracts. Many uses have been proposed for Ethereum platform, including ones that are impossible or unfeasible. Use case proposals have included finance, the internet-of-things, farm-to-table produce, electricity sourcing and pricing, and sports betting. Ethereum is (as of 2017) the leading blockchain platform for initial coin offering projects, with over 50% market share.

As of January 2018, there are more than 250 live DApps, with hundreds more under development. Project applications listed in this section are not exhaustive and may be outdated.

  • Digital signatures that ensure authenticity and proof of existence of documents: the Luxembourg Stock Exchange has developed such a system
  • Slock.It is developing smart locks
  • Digital tokens pegged to fiat currencies: Dai, stablecoin pegged to US dollar. Decentralized Capital. Spanish bank Santander is also involved in such a project.
  • Digital tokens pegged to gold: Digix
  • Improved digital rights management for music: Imogen Heap used the technology
  • Platforms for prediction markets: Augur, Gnosis Stox
  • Platforms for crowdfunding: the DAO
  • Social media platforms with economic incentives: Backfeed, Akasha
  • Decentralized marketplaces: FreeMyVunk, TransActive Grid
  • Remittance: Everex
  • Online gambling: CoinPoker,Etheroll
  • Electric car charging management: RWE
  • Secure identity systems for the Internet: uPort
  • Labour economics: Blocklancer, Ethlance
  • Video games: CryptoKitties' popularity in December 2017 caused the Ethereum network to slow down.
  • Financial exchanges: EverMarkets Exchange, a 'hybrid decentralized' exchange for trading global futures contracts'

Enterprise software

Ethereum-based customized software and networks, independent from the public Ethereum chain, are being tested by enterprise software companies. Interested parties include Microsoft, IBM, JPMorgan Chase, Deloitte, R3, Innovate UK (cross-border payments prototype). Barclays, UBS and Credit Suisse are experimenting with Ethereum blockchain to automate Markets in Financial Instruments Directive (MiFID) II requirements.

Permissioned ledgers

Ethereum-based permissioned blockchain variants are used and being investigated for various projects.

  • J. P. Morgan Chase is developing a permissioned-variant of Ethereum blockchain dubbed "Quorum". It's designed to toe the line between private and public in the realm of shuffling derivatives and payments. The idea is to satisfy regulators who need seamless access to financial goings-on, while protecting the privacy of parties that don't wish to reveal their identities nor the details of their transactions to the general public.
  • Royal Bank of Scotland has announced that it has built a Clearing and Settlement Mechanism (CSM) based on the Ethereum distributed ledger and smart contract platform.

Performance

In Ethereum all smart contracts are stored publicly on every node of the blockchain, which has costs. Being a blockchain means it is secure by design and is an example of a distributed computing system with high Byzantine fault tolerance. The downside is that performance issues arise in that every node is calculating all the smart contracts in real time, resulting in lower speeds. As of January 2016, the Ethereum protocol could process 25 transactions per second. On 19 December 2016, Ethereum exceeded one million transactions in a single day for the first time.

  • Micro Raiden was launched November 2017.
  • Buterin and Joseph Poon (a co-author of Bitcoin's lightning network whitepaper) announced in 2017 their plan to launch a scaling solution called Plasma which creates "child" blockchains to the "main" parent blockchain. The plasma project has skeptics; specifically, Vlad Zamfir (Ethereum's lead researcher on proof of stake) has publicly questioned the plasma project's viability.
  • Ethereum engineers have been working on sharding the calculations, and the next step (called Ethereum 2) was presented at Devcon 3.

Ethereum's blockchain uses Merkle trees, for security reasons, to improve scalability, and to optimize transaction hashing. As with any Merkle tree implementation, it allows for storage savings, set membership proofs (called "Merkle proofs"), and light client synchronization.


How Millions of Dollars in Ethereum Remain at Security Risk
src: cdn.wccftech.com


Ethereum forks

Ethereum-based cryptocurrencies that emerged from forking the Ethereum blockchain:

  • Ethereum Classic
  • Expanse

ERC20 tokens that function within the Ethereum ecosystem are also referred as Ethereum tokens.


Ethereum hits record high; bitcoin briefly climbs back above $17,000
src: fm.cnbc.com


Criticisms

A finance blogger on FT Alphaville has pointed out that criminals are using Ethereum to run Ponzi schemes and other forms of investment fraud. The article was based on a paper from the University of Cagliari, which placed the number of Ethereum smart contracts which facilitate Ponzi schemes at nearly 10% of 1384 smart contracts examined. However, it also estimated that only 0.05% of the transactions on the network were related to such contracts.


ethereum Archives - Trade with Profit
src: tradewithprofit.com


References


Bitcoin, Ethereum or Litecoin: Which is best for you? | ELEVENEWS
src: elevenews.com


External links

  • Official website

Source of the article : Wikipedia

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