Several generation technologies of Ethereum blockchain
what is Ethereum:
Ethereum is an innovation based on the application of technologies and concepts in bitcoin to computers. Ethereum itself imitates a lot of bitcoin technology to maintain the computer platform. blockchain technology is one of them
Ethereum platform can safely run any program users want
advantages of Ethereum over other competitive currencies before Ethereum appeared, some digital currencies imitated bitcoin. However, these projects have their own shortcomings, they can only support one or several specific applications at the same time< However, the reason why Ethereum can surpass the limitations of these projects in the past is because of the core idea of Ethereum
what Ethereum wants to implement is a blockchain protocol with built-in programming language. Since it supports programming language, in theory, any blockchain application can be defined with this language, and then run on Ethereum's blockchain protocol as an application
The design of Ethereum is very flexible and adaptable
Ethereum target sets the advantages of blockchain technology, in order to add the advantages of blockchain, such as decentralization, openness and security, to almost all computing fields
blockchain applications of Ethereum
Ethereum has many blockchain applications, such as digital applications of gold and stocks, financial derivatives applications, DNS and digital authentication, etc
Ethereum has achieved more than 100 blockchain applications by many start-ups
Ethereum has also been closely watched by some financial institutions, banking consortia (such as R3), as well as large companies like Samsung, Deloitte, RWE and IBM. As a result, a number of blockchain applications such as simplified and automated financial transactions, merchant loyalty index tracking, and gift cards designed to achieve decentralization of electronic transactions have emerged
the relationship between Ethereum and blockchain:
Ethereum is a programmable blockchain
Ethereum does not give users a series of preset operations (such as bitcoin transaction), but allows users to create complex operations according to their own wishes
in this way, Ethereum can be used as a platform for various types of decentralized blockchain applications, including but not limited to cryptocurrency
like other blockchains, Ethereum also has a peer-to-peer network protocol. Ethereum blockchain database is maintained and updated by many nodes connected to the network. Each network node runs the Ethereum simulator and executes the same instructions. Therefore, people sometimes call Ethereum "world computer"
Blockchain 1.0 era usually refers to the development stage of blockchain application represented by bitcoin from 2009 to 2014. They are mainly committed to solving the problem of decentralization of currency and means of payment; After 2014, developers pay more and more attention to solve the technical and scalability problems of bitcoin. At the end of 2013, vitalik buterin released Ethereum white paper "Ethereum: next generation smart contract and decentralized application platform", which introced smart contract into blockchain and opened the application of blockchain outside the currency field, thus opening the era of blockchain 2.0< The so-called smart contract is actually a kind of computer contract that can be automatically executed based on prescribed trigger rules. It can also be regarded as a digital version of traditional contract. It was proposed by interdisciplinary legal scholar and cryptography researcher Nick Szabo more than 20 years ago. This technology was once not used in the actual instry because of the lack of programmable digital system and related technologies, until the emergence of blockchain technology and Ethereum provided a trusted execution environment for it
compared with bitcoin, Ethereum is a complete scripting language of Turing, which supports developers to create and publish arbitrary decentralized applications on the platform. Since its birth, there have been more than 200 decentralized applications based on Ethereum in the world
the chief researcher of bitwindow blockchain said: in the era of blockchain 2.0 represented by Ethereum, blockchain technology has graally expanded from the field of currency and payment to the field of finance. With the development of technology and the wider application of blockchain, the era of blockchain 3.0 beyond the monetary and financial fields will be around the corner. This article is excerpted from bitwindow. China's professional blockchain and digital currency instry analyzes the media, and adheres to a neutral, objective and dialectical attitude to understand and interpret the latest trends of blockchain and digital currency
1. Blockchain links
as the name suggests, blockchain is a chain composed of blocks. Each block is divided into block head and block body (including transaction data). The block head includes the prevhash value (also known as hash value) of the previous block used to realize the block link and the random number (nonce) used to calculate the mining difficulty. The hash value of the previous block is actually the hash value of the head of the previous block, and the random number calculation rule determines which miner can obtain the right to record the block
2. Consensus mechanism
blockchain is accompanied by the birth of bitcoin, which is the basic technology architecture of bitcoin. Blockchain can be understood as an Internet-based decentralized accounting system. A decentralized digital currency system like bitcoin requires the consistency of accounting of honest nodes without a central node, which needs blockchain to complete. Therefore, the core of blockchain technology is a consensus mechanism to reach a consensus on the legitimacy of transactions between indivials without mutual trust without central control
there are four main types of consensus mechanisms in blockchain: pow, POS, dpos and distributed consistency algorithm
3. Unlocking script
script is an important technology to realize automatic verification and contract execution on blockchain. Every output of every transaction does not point to an address in the strict sense, but to a script. A script is like a set of rules that constrain how the receiver can spend the asset locked on the output
the validation of transactions also depends on scripts. At present, it depends on two kinds of scripts: Lock script and unlock script. Locking script is a condition added to the output transaction, which is realized by a script language and located in the output of the transaction. The unlocking script corresponds to the locking script. Only when the conditions required by the locking script are met can the assets corresponding to the script be spent, which is located in the input of the transaction. Many flexible conditions can be expressed by script language. Interpretation script is similar to the "virtual machine" in our programming field, which runs in every node of the blockchain network in a distributed way
4. Transaction rules
blockchain transaction is not only the basic unit of a block, but also the actual effective content recorded by the blockchain. A blockchain transaction can be a transfer, or the deployment of smart contracts and other transactions
as far as bitcoin is concerned, a transaction refers to a single payment transfer. The transaction rules are as follows:
1) the input and output of the transaction cannot be empty
2) for each input of a transaction, if its corresponding utxo output can be found in the current transaction pool, the transaction will be rejected. Because the current transaction pool is the transaction not recorded in the blockchain, and each input of the transaction should come from the confirmed utxo. If it is found in the current trading pool, it is Shuanghua trading
3) for each input in a transaction, the corresponding output must be utxo
4) each input unlocking script must verify the compliance of the transaction together with the corresponding output locking script
5. Transaction priority
the priority of blockchain transaction is determined by the blockchain protocol rules. For bitcoin, the priority of a transaction to be included in a block is determined by the time when the transaction is broadcast to the network and the amount of the transaction. With the increase of transaction broadcast time on the network and the increase of transaction chain age, the priority of transaction will be improved and eventually be included by the block. For Ethereum, the priority of the transaction is also related to the transaction fee that the publisher is willing to pay. The higher the transaction fee that the publisher is willing to pay, the higher the priority that the transaction is included in the block
6. Merkle proof
the original application of Merkle proof is bitcoin, which was described and created by Satoshi Nakamoto in 2009. Bitcoin blockchain uses Merkle proof to store transactions in each block. So that the transaction can not be tampered with, but also easy to verify whether the transaction is included in a specific block
7. RLP
RLP (recursive length prefix) is one of the main encoding methods of object serialization in Ethereum. Its purpose is to encode the sequence of arbitrary nested binary data.
1. Lianzhuang data block structure based on blocks
2. Network wide shared ledger
3. Asymmetric encryption
4. Source code open source
blockchain 2.0 era technical basis:
1. Smart contract; It is an application in the blockchain system. It is a business logic that can run automatically by coding. It usually has its own token and special development language
2. DAPP: it includes the user's applications, including but not limited to various cryptocurrencies, such as Ethereum wallet
3. Virtual machine: used to execute the compiled code of smart contract. Virtual machine is Turing complete
with the application and deepening of blockchain technology, the era of blockchain 3.0 has come. The mode of blockchain cooperation can be seen from behind the operation of all walks of life. Therefore, blockchain will change the way of human life widely and profoundly, so the whole life service will enter the era of blockchain. In the process of Internet development, blockchain + physical instry, blockchain e-commerce and blockchain community operation can be applied to blockchain technology
of course, 3.0 came into being with the development of modern cryptography. Today's applied cryptography is the result of cryptography 20 years ago. Therefore, in order to apply blockchain technology to more participation scenarios, especially in Internet economy and other aspects, more verification is needed to verify whether the existing encryption technology can meet the demand, and more in-depth integration of cryptographic frontier technology and continuous innovation are needed.
blockchain 1.0 mainly refers to bitcoin. Blockchain 2.0 extends to all assets, while blockchain 3.0 goes beyond currency, finance, even commerce, and all areas of our lives, including politics, social relations, ecation, medical care, etc. According to the prediction and conception of people in the instry, the era of blockchain 3.0 will be realized in the next five years. At that time, blockchain will be recognized and accepted by all the public like the Internet, thus completely subverting our lives
McKinsey has submitted a technical report on blockchain to the Federal Insurance Advisory Committee of the United States. The report calls 2009-2016 the "Dark Age" and believes that all blockchain solutions ring this period are based on bitcoin, and the new era of blockchain will begin in 2016. At that time, the application of blockchain will become unprecedented. Applying an original sentence in McKinsey report: Based on the current development speed of blockchain, we believe that blockchain solutions may realize their full potential in the next five years.
DAPP is the abbreviation of decentralized application, which translates into decentralized application, also known as distributed application. Compared with the app we are familiar with, DAPP does not rely on IOS and Android system development, but is put on the blockchain system and combined with smart contract. DAPP is to blockchain just as app is to IOS and Android
generally, different dapps will adopt different underlying blockchain development platforms and consensus mechanisms, or issue their own tokens, or use common tokens based on the same blockchain platform. However, DAPP can not be developed on all blockchains, but must use a public blockchain platform with smart contract function. It allows anyone to build and use distributed applications running through blockchain technology, such as Ethereum and EOS.
network layer: blockchain network is essentially a P2P (peer-to-peer) network. The resources and services in the network are distributed on all nodes, and the information transmission and service implementation are directly carried out between nodes, without the intervention of intermediate links and servers. Each node not only receives information, but also generates information. Nodes synchronize information by maintaining a common blockchain. When a node creates a new block, it notifies other nodes in the form of broadcast. After receiving the information, other nodes verify the block and create a new block on the basis of the block, So as to achieve the role of the whole network to jointly maintain a bottom ledger. Therefore, the network layer will involve the design of P2P network, propagation mechanism and verification mechanism. Obviously, these designs can affect the confirmation speed of block information. The network layer can be used as a research direction in the scalable scheme of blockchain technology
data layer: the underlying data of blockchain is a data structure of block + linked list, which includes data block, chain structure, timestamp, hash function, Merkle tree, asymmetric encryption, etc. Among them, data block and chain structure can be used as the improvement direction of data layer research in the extensible scheme of blockchain technology
consensus layer: it is the basis for highly dispersed nodes to reach a fast consensus on the effectiveness of block data. The main consensus mechanisms include pow (proof of work), POS (proof of stake), dpos (delegated proof of stake) and pbft (Practical Byzantine fault tolerance), They have always been the highlight of the scalable solution of blockchain technology
incentive layer: it is a common mining mechanism, which is used to design certain economic incentive model and encourage nodes to participate in the security verification of blockchain, including the design of issuance mechanism and allocation mechanism. Improvements at this level do not seem to be directly related to blockchain scalability
Contract layer: mainly refers to various script codes, algorithm mechanisms and smart contracts. Strictly speaking, this layer of the first generation blockchain is missing, so they can only trade, and can not be used in other fields or other logical processing. The emergence of the contract layer makes it a reality to use blockchain in other fields. This part of Ethereum includes EVM (Ethereum virtual machine) and smart contract. The improvement of this level seems to provide a potential new direction for the scalability of the blockchain, but it does not seem to be directly related to the application layer in terms of structure
it is the display layer of the blockchain, including various application scenarios and cases. For example, Ethereum uses truffle and Web3 JS. The application layer of blockchain can be mobile terminal, Web terminal, or integrated into the existing server, taking the current business server as the application layer. The improvement of this level also seems to provide a potential new direction for the expansion of blockchain, but structurally, it doesn't seem to be directly related
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