Development of Ethereum wallet system
EOS is a public chain system at the bottom of blockchain developed by block. One, which is specially designed to support decentralized application of Commerce, and its code is open source
bitcoin is called blockchain 1.0 because it opens up the world of digital cryptocurrency and takes a decisive step from 0 to 1
Ethereum is known as blockchain 2.0, because it provides Turing complete virtual machine that can run smart contracts, bringing unlimited possibilities
and EOS is called blockchain 3.0, why? Two words: performance
The positioning of EOS is the slogan of its home page:English: the most powerful infrastructure for decentralized applications
Chinese: the most powerful decentralized application infrastructure
EOS expects to be an enhanced version of Ethereum, a high-throughput intelligent contract platform
although Ethereum has complete functions, it is limited by its design choice. Due to the block output speed of 15 seconds, the transaction throughput is far from large-scale practical level, which is only about 30 ~ 40tps (transaction / s). EOS, on the other hand, has chosen a different technology route, with the goal of achieving a considerable million TPS, which is quite attractive considering visa's actual processing speed of 1700tps
consensus mechanism of EOS
the reason why the throughput of bitcoin and Ethereum is so low is that they are constrained by the application scenario they envision and the consensus mechanism they choose for the scenario - both of them assume that the environment in which the system runs is totally untrustworthy, so they both adopt the consensus mechanism of proof of work
consensus, as the name suggests, is to reach a unified understanding of something - for blockchain, something refers to the confirmation of the transaction - any node to submit a transaction needs everyone's approval
the pow mechanism currently adopted by bitcoin and Ethereum is the design of the legendary Nakamoto Tsung. Under this mechanism, in order to obtain the bookkeeping right and digital currency reward, miners need to constantly dig for the compliant hash value, and confirm and package the transaction data through the consensus of hash value. POW has no access threshold, and any node has equal rights to participate in bookkeeping. Of course, the probability of winning is related to computing power:
the price of ram is based on Bancor algorithm, that is, it is regulated by market supply and demand: if the supply of ram exceeds the demand, more EOS certificates are needed to buy ram, At this time, more EOS certificates can be obtained by selling ram
memory is a consuming resource, which cannot be redeemed and can only be bought and sold. Take the issue of currency on EOS as an example. At present, the issue of currency requires 20m of memory. An EOS can buy 20KB. According to the current storage price, issuing a currency will consume 1000 EOS. This is the source of EOS memory consumption
Course Overview
this course is for friends who are interested in the development of EOS decentralized application. The course covers the core concepts of EOS DAPP development, the development and deployment of smart contracts, and how the front page interacts with EOS blockchain. Finally, a complete DAPP development based on react and EOS is completed
Chapter 1: enter the world of EOS
to understand the core concepts of EOS, such as positioning and characteristics, consensus mechanism, payment computing model, etc
Chapter 2: Hi EOS
understand the overall framework of EOS node software and the functions of node server, wallet server and command-line tools, learn how to configure and start EOS node server and wallet server, and preliminarily understand the use of command-line tools
Chapter 3: wallet, key and account
understand the three core concepts related to personal identity in EOS: wallet, key and account, and learn how to use command-line tools to create wallet, key and account
Chapter 4: development and interaction of smart contracts
understand the concept and function of smart contracts, learn how to write and compile EOS smart contracts, and learn how to deploy and interact with contracts using command-line tools
understand the persistence mechanism of state in EOS smart contract, and learn to use multi index table to save contract state
Chapter 5: issue your own tokens
learn the principle and implementation mechanism of issuing tokens on EOS, and master how to use command-line tools to issue, transfer and view the balance of tokens through practical operation
Chapter 6: use code to interact with smart contract
understand the principle of interaction between application and EOS blockchain, and learn to use JSON RPC interface and eosjs encapsulation library to access EOS blockchain
Chapter 7: DAPP development of practical notes
comprehensively use EOS knowledge, use react to complete a decentralized application of EOS notes, and learn the complete process from requirement analysis to code implementation
The above course address is as follows: EOS tutorialcompared with bitcoin, the biggest difference of Ethereum is that it can support a more powerful scripting language (technically speaking, Turing's complete scripting language), allowing developers to develop any application and implement any smart contract on it, which is also the most powerful point of Ethereum. As a platform, Ethereum can be compared with Apple's app store, on which any developer can develop applications and sell them to users. Each type of financial contract can be written as a smart contract in the form of program code<
the Xueshuo innovation blockchain Technology Workstation of Lianqiao ecation online is the only approved "blockchain Technology Specialty" pilot workstation of "smart learning workshop 2020 Xueshuo innovation workstation" launched by the school planning, construction and development center of the Ministry of ecation of China. Based on providing diversified growth paths for students, the professional station promotes the reform of the training mode of the combination of professional degree research, proction, learning and research, and constructs the applied and compound talent training system.
how many stages is the blockchain divided into&# 8194;
there are 1.0, 2.0 and 3.0 blockchains, and the digital currency dominated by bitcoin is blockchain 1.0; The smart contract platform centered on Ethernet is blockchain 2.0; The application scenario and platform of high-performance blockchain is blockchain 3.0. The simple conclusion is that 1.0 is mining and currency speculation; 2.0 is ICO and currency; 3.0 is the implementation of the project. The real landing projects are still far away from us. Most projects take stage 2.0 as the entry point of instry solutions. The combination of blockchain and instry enables blockchain to be applied in a certain instry&# 8194;
how to be a qualified blockchain project&# 8194; potential blockchain projects have different evaluation standards and different periods. The main reason for the outbreak of digital currency in 2017 is the promotion of ICO and Ethernet smart contract. In the past, projects that could meet these two conditions were considered good. Now, the measurement standard of projects is: & (1) There are application scenarios. The project itself has team, goal and real scene application. Because some teams or enterprises are not suitable for blockchain applications, it is a rather crude way to establish a connection between them&# 8194;&# 8194;&# 8194;&# 8194;&# 8194; (2) the multi parties involved in the blockchain can generate transactions (3) blockchain has a large number of communities and users. In conclusion, good blockchain projects can be applied refer to the case of Henan keoo Information Technology Co., Ltd
the first one is the Internet company that mainly sells templates
the advantages are: low price, can be done between thousands of yuan to 10000 yuan, convenient, can be quickly online
the disadvantages are: it's troublesome to modify the function, so we need to avoid the trap of low price. We don't find that the money spent on the template modification function is more expensive than buying the template in the end. And it's not independent. A template is sold to many businesses and households. The template is not used permanently. Generally, it has to pay an annual fee every year
the second is the mainstream way, which is a network company focusing on customized development
the advantages are: unique, customized for your enterprise or store. You can set the function and ask for it. It's convenient to modify bug later, and it's also very convenient to change things. The most important thing is the permanent right of use
the disadvantage is: the relative price is relatively high!!! The basic cost of the customized version ranges from tens of thousands to more than 100000 yuan! But there's a reason why it's expensive. After all, the functions are more comprehensive
finally, what kind of small program development company should we look for? How much does it cost to develop? It depends on the budget prepared by your company! Hope to be useful to you!
Xu Mingxing: founder of okcoin, technical otaku, and now CEO of the company
He Yi: former host of a tourism channel, later joined okcoin, mainly responsible for participating in some instry activities and promotion activities, and now is the vice CEO of the company<
Zhao CHANGPENG: he used to be the head of blockchain China, a world-famous online wallet. Later, he moved to okcoin, mainly responsible for the development of platform technology and projects
this is the legendary bitcoin tiantuan of okcoin
in the bitcoin mining instry, Zhang Nangeng is the founder of Avalon. It is his mining machine that has completely subverted the bitcoin mining instry and is currently deploying large-scale mines.