Ethereum and super ledger business
blockchain includes public blockchain, joint (instry) blockchain and private blockchain. Public chain point-to-point e-cash system: bitcoin, smart contract and decentralized application platform: Ethereum
blockchain is a new application mode of distributed data storage, point-to-point transmission, consensus mechanism, encryption algorithm and other computer technologies
blockchain is an important concept of bitcoin. In essence, it is a decentralized database. At the same time, as the underlying technology of bitcoin, it is a series of data blocks generated by using cryptographic methods. Each data block contains a batch of bitcoin network transaction information, Used to verify the validity of its information (anti-counterfeiting) and generate the next block
extended data
according to the different degree of blockchain network centralization, three kinds of blockchains under different application scenarios are differentiated:
1. The blockchain with the whole network open and without user authorization mechanism is called public chain
2. The authorized nodes are allowed to join the network, and the information can be viewed according to the authority. It is often used in the inter agency blockchain, which is called alliance chain or instry chain
3. All the nodes in the network are in the hands of one organization, which is called private chain
alliance chain and private chain are also called licensing chain, and public chain is called non licensing chain
blockchain features
1, decentralization. Blockchain technology does not rely on additional third-party management institutions or hardware facilities, and there is no central control. In addition to the self-contained blockchain itself, each node realizes information self verification, transmission and management through distributed accounting and storage. Decentralization is the most prominent and essential feature of blockchain
2. Openness. Blockchain technology is based on open source. In addition to the private information of all parties involved in the transaction is encrypted, the data of blockchain is open to everyone. Anyone can query blockchain data and develop related applications through the open interface, so the information of the whole system is highly transparent
3. Independence. Based on consensus specifications and Protocols (similar to various mathematical algorithms such as hash algorithm used by bitcoin), the whole blockchain system does not rely on other third parties, and all nodes can automatically and safely verify and exchange data in the system without any human intervention
4. Safety. As long as 51% of all data nodes cannot be controlled, the network data cannot be arbitrarily manipulated and modified, which makes the blockchain itself relatively safe and avoids subjective and artificial data changes
5. Anonymity. Unless there are legal requirements, technically speaking, the identity information of each block node does not need to be disclosed or verified, and the information can be transferred anonymously
a total of 22 weeks, divided into five stages,
the first stage is 4 weeks, go language foundation and network concurrency, learning the introctory go language,
the second stage is 4 weeks, go language practical web development, crawler development, cryptography, consensus algorithm, realizing lightweight public chain, learning the website and crawler that can develop golang, Achieve lightweight blockchain
stage 3, 4-week Ethereum source code analysis and smart contract DAPP development, master Ethereum core and smart contract development, as well as blockchain,
stage 4, 4-week super ledger, bitcoin EOS, source code analysis and smart contract practice, master super ledger development, cat bitcoin, bifurcated EOS after learning, As well as DAPP development of smart contract
phase 5, 6-week project practice, five enterprise level projects, and one year of blockchain project experience after learning
from the characteristics of the language itself, go is a very efficient language, which highly supports concurrency. Go language itself pays more attention to distributed system, and concurrency processing is relatively good, such as advertising and search, That kind of high concurrency server
go language advantages:
excellent performance, can be directly compiled into machine code, does not rely on other libraries, go is extremely fast. Its performance is similar to Java or C + +
concurrency is supported at the language level, which is the biggest feature of go. It is born to support concurrency, and go is the concurrency supported in gene, which can make full use of multi-core and make it easy to use concurrency
the built-in runtime supports garbage collection, which is one of the features of dynamic language. Although GC is not perfect at present, it is enough to cope with most of the situations we can encounter, especially GC after go1.1
it's easy to learn. The authors of go language all have the gene of C, so go naturally has the gene of C. There are 25 go keywords, but the expressive ability is very strong. It almost supports most of the features you've seen in other languages: inheritance, overloading, object, etc
rich standard libraries, go has built a large number of libraries, especially the network library, which is also my favorite part< As like as two peas, br / > built-in powerful tools, Go language is built with many tools chain, the best should be gofmt tools, automatic formatting code, make team review become so simple, code format is exactly the same, it is very difficult to think differently.
cross platform compilation and fast compilation. Compared with the sluggish compilation speed of Java and C + +, the fast compilation time of go is a major efficiency advantage
disadvantages of go language:
package management: package management of go language is absolutely not perfect. By default, it has no way to make a specific version of the dependency library, nor can it create replicable builds. In contrast, python, node and Ruby all have better package management systems. However, with the right tools, the package management of go language can also perform well
lack of development framework: go language does not have a major framework, such as Ruby's rails framework, Python's Django framework or PHP's laravel. This is a heated discussion in the go language community, because many people think that we should not start with using frameworks. This is true in many cases, but if you just want to build a simple crud API, it's much easier to use Django / djrf, rails laravel, or Phoenix
exception handling: go language can help developers deal with compilation errors by simply returning errors (or call stack) through functions and expected calling codes. Although this method is effective, it is easy to lose the scope of the error, so it is difficult to provide meaningful error information to users. Error package can solve this problem by allowing us to add context and stack trace to return error
another problem is that we may forget to handle errors. Static analysis tools such as errcheck and megacheck can avoid these errors. Although these solutions are very effective, they may not be the right way.
2 FORTRAN 95 programming, written by Peng Guolun
3 Introction to FORTRAN 77 and 90 / 95 programming, written by Ding Zejun
4. Out of control: the new biology of machines, society and economy
5. Necessity, written by Kevin Kelly, mentions 12 inevitable trends in the next 20 years
6. Master bitcoin, this book will provide you with the necessary knowledge to guide you into the bitcoin world
7. Blockchain revolution, written by don Tapscott and Alex Tapscott, tells how the underlying technology of bitcoin has changed money, business and the world
8. Blueprint and guide of blockchain new economy, written by Melanie Swann
9. Blockchain: the concept of quantum wealth, written by Han Feng / Zhang Xiaomei
10. Logic of finance, The author is Chen Zhiwu. The work starts from the cultural and institutional genes of wealth in simple terms, so as to tell readers what the logic of finance is
related books include principles of economics, blockchain: technology driven finance, blockchain Revolution: how bitcoin's underlying technology can change money Business and the world, blockchain technology guide, illustrated blockchain, how blockchain will redefine the world, digital currency: bitcoin data reporting and operation guide, blockchain: from digital currency to credit society, intelligent age, etc. to be honest, blockchain is still a hot resource. It's mainly about judgment (whether it's valuable) and action (to get in early)
recommends a block chain related APP, called golden finance, recommends a public official account, called "Xiao Ke online". The article is rich in materials;
Global blockchain instry investment is hot
according to the data of the "in-depth analysis report on business model innovation and investment opportunities of blockchain instry" released by prospective instry research institute, as of the end of April 2017, there were 455 blockchain companies in the world, with a total financing amount of US $1.947 billion. Among them, the total investment and financing of us blockchain related companies reached US $1.252 billion, accounting for 64.3% of the global market; The total financing amount of China's blockchain emerging enterprises is about US $114 million, accounting for 5.86%, ranking second in the world after the United States, and growing rapidly
at present, the overall survival status of blockchain is good, with a survival rate of 87.25%. Among all the companies, 47 have been closed, accounting for about 10.51%, and the other 10 have been acquired. Due to the change of competition pattern in bitcoin market, some companies have been forced to shut down. Meanwhile, some coin circle companies are graally transforming to chain circle companies.
exploration at the national level has also begun. On March 23, the information technology and Software Services Department of the Ministry of instry and information technology announced that it will study and explore the application of blockchain in the instrial field. Previously, the Ministry of instry and information technology said that it was preparing to establish a National Technical Committee for standardization of blockchain and distributed accounting technology to explore the formation of a complete blockchain standard system to better serve the development of blockchain technology instry.
there is no central server in Ethereum. Instead, there are many equal nodes connected by P2P protocol, which store all the data in many nodes. When a user initiates a transaction, the transaction will be broadcast out through P2P protocol. The miner node verifies, packages and further broadcasts the transaction to the whole network. After confirmation in the blockchain, the operation is considered to be unchangeable
in the articles on blockchain on the Internet, the two words distributed and decentralized are mentioned, sometimes slightly different, sometimes mixed. The author thinks that if we want to distinguish accurately, the distributed system emphasizes that multiple components work together by sending messages, and the decentralized system emphasizes that there is no central node to control the operation of the whole system. Therefore, we think that Ethereum is both decentralized and distributed, or running a decentralized program on a distributed platform.
Ledger is a book with a certain format and several account pages. Based on the accounting documents, it records all economic business in chronological order and classification, which is what we usually call the ledger. Blockchain represents a unique data record format. Blockchain is "block + Chain". The so-called block is the meaning of data block. Each block is connected by a certain mark to form a chain
Super ledger
hyperledger (Chinese name is super ledger, collectively referred to as hyperledger) is an open source project launched by Linux foundation in 2015 to promote blockchain digital technology and transaction verification. The goal of hyperledger is to enable members to work together to build an open platform to meet the needs of various users from different instries, while greatly simplifying the business process. The founding members of hyperedge include IBM, Intel, Cisco and other large companies. By the end of this book, more than 183 organizations and companies have joined hyperedge, and they are growing rapidly
at the beginning of hyperledger project, Linux foundation has received a number of different code bases, including IBM code base (inspired by Ethereum to a certain extent), Dah (bits of proof bitcoin code base) and sockstream code base (an extension of bitcoin code base). In addition, there are digital asset and ripple contributions. With the development of the instry, a single project has been unable to meet the needs of the business, so hyperledger has graally developed from a single project into a project group. At present, hyperledger is not a specific technology, but a set of blockchain technology frameworks. Up to now, the hyperledger project team contains 9 formal projects and more than 50 moles related to these formal projects
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
Hyperledger is an open source project launched by Linux foundation in 2015 to promote blockchain digital technology and transaction verification. It is composed of 30 initial enterprise members (including IBM, Accenture, Intel, J.P. Morgan, R3, Dah, DTCC, Fujitsu, Hitachi, swift, Cisco, etc.). The goal is to let members work together to build an open platform, meet various user cases from different instries, and simplify business processes
Solidness language is a special language for writing and executing smart contracts. It is a contract oriented high-level language running on the basis of Ethereum virtual machine. It was first proposed by the former CTO and co-founder Gavin wood of Ethereum in August 2014. Later, Ethereum developers set up a special team to continuously improve solidness language, At present, it is still under development and optimization. The development storage area on GitHub is HTPs / github.com/thereum/solidness. Here we can learn the most comprehensive details and related documents about the development and iteration process of solidness language. In terms of language style, solid language is deeply influenced by C + +, Python and JavaScript. It is a static programming language, compiled in bytecode mode, so it can run on Ethereum virtual machine. Gavin wood uses the syntax rules of ECMAScript scripting language of JavaScript for reference when developing solid language, which makes it somewhat similar to the existing web development language, but it is quite different. For example, solid language has static type, variable return function and so on. The most important point is that solid language can write contracts with self executing business logic and embedded in smart contracts. Therefore, it is not only one of the basic programming languages of Ethereum, but also the basic programming languages of most other Ethereum based blockchain procts (blockchain 2.0) with smart contracts, It is widely used in the vast majority of blockchain procts, such as hyperledger project, which is developed with soliditv language
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