Composition of blockchain syllabus
From the perspective of technology and architecture, I will tell you my understanding of blockchain in common language
what is blockchain? In a word, blockchain is a storage system. To be more specific, blockchain is a distributed storage system without an administrator and each node has all the data
What are the common storage systems like
first, how to ensure high availability
the common storage system usually uses "rendancy" to solve the problem of high availability. As shown in the figure above, if the data can be copied into several copies and rendant to multiple places, high availability can be guaranteed. The data in one place is hung, and there is data in other places. For example, the master-slave cluster of MySQL is the same principle, and the raid of disk is also the same principle
two points need to be emphasized in this place are: data rendancy often leads to consistency problems
1. For example, in the master-slave cluster of MySQL, there is actually a delay in reading and writing, which means there is a inconsistency in reading and writing in a short period of time. This is a side effect of data rendancy
The second point is that data rendancy often reces the efficiency of writing, because data synchronization also consumes resources. If you add two slave libraries, the write efficiency will be affected. The common storage system is to use rendancy to ensure the high availability of dataso the second question, ordinary storage system, can write more
the answer is yes, for example, take this graph as an example:
in fact, MySQL can do a master-slave synchronization of al masters, master-slave synchronization of al masters, two nodes can be written at the same time. If you want to do a multi room multi live data center, in fact, multi room multi live data synchronization. What we should emphasize here is that multi-point writing often leads to the consistency problem of writing conflicts. Take MySQL as an example, suppose that the attribute of a table is self incrementing ID, then the data in the database is 1234 now. If one of the nodes writes and inserts a piece of data, it may become 5, and then these 5 pieces of data are synchronized to another master node, Before synchronization, if another write node inserts a piece of data, a piece of data with self incrementing ID of 5 will be generated. Then, after the generation, synchronize to another node, and the synchronized data will conflict with the two local 5's after it arrives, which will lead to synchronization failure and write consistency conflict. This problem will occur in the case of multi-point writing
how to ensure consistency in multi-point writing
the reform "Swan class" gives you more technical work
among them, the data layer encapsulates the underlying data block and related data encryption and timestamp technologies; The network layer includes distributed networking mechanism, data transmission mechanism and data verification mechanism; The consensus layer mainly encapsulates all kinds of consensus algorithms of network nodes; The incentive layer integrates economic factors into the blockchain technology system, mainly including the issuance mechanism and distribution mechanism of economic incentives; The contract layer mainly encapsulates all kinds of scripts, algorithms and smart contracts, which is the basis of the programmable characteristics of blockchain; The application layer encapsulates various application scenarios and cases of blockchain. In this model, chain block structure based on timestamp, consensus mechanism of distributed nodes, economic incentive based on consensus computing power and flexible and programmable smart contract are the most representative innovations of blockchain technology.
2-The distributed database is the physical carrier of the blockchain, and the blockchain is the logical carrier of the transaction. All core nodes should contain the full of the blockchain data
3-The blockchain serializes the blocks according to time, and the blockchain is the only body of the whole network transaction data
4-The blockchain is only effective for adding, Invalid for other operations
5-public-private key verification based on asymmetric encryption
6-accounting node requires that Byzantine general problem can be solved / avoided
7-consensus progress is evolutionarily stable, that is, it will not collapse in the face of a certain amount of contradictory data of different nodes
8-consensus process can solve the problem of double spending
five characteristics of blockchain:
decentralized
e to the use of Distributed Accounting and storage, there is no centralized hardware or management organization, the rights and obligations of any node are equal, and the data blocks in the system are jointly maintained by the nodes with maintenance function in the whole system
thanks to the decentralization of blockchain, bitcoin also has the characteristics of decentralization [6]
openness
the system is open, in addition to the private information of all parties to the transaction is encrypted, the data of the blockchain is open to all, and anyone can query the blockchain data and develop related applications through the open interface, so the information of the whole system is highly transparent
autonomy
blockchain adopts consensus based specifications and Protocols (such as a set of open and transparent algorithms) to enable all nodes in the whole system to exchange data freely and safely in a de trusted environment, so that the trust in "people" is changed into the trust in machines, and any human intervention does not work
information cannot be tampered with
once the information is verified and added to the blockchain, it will be stored permanently. Unless more than 51% of the nodes in the system can be controlled at the same time, the modification of the database on a single node is invalid, so the data stability and reliability of the blockchain are extremely high<
anonymity
since the exchange between nodes follows a fixed algorithm, their data interaction does not need trust (the program rules in the blockchain will judge whether the activity is effective by themselves), so the counterparties do not need to let the counterparties generate their own trust by disclosing their identities, which is very helpful for credit accumulation.
How many weeks is the
go full stack + blockchain course? How many stages? How long does each stage last? What is the degree of completion of each stage
a total of 22 weeks, divided into five stages,
the first stage 4 weeks go language foundation and network concurrency, after learning the introctory go language,
the second stage 4 weeks go language practical web development, crawler development, cryptography, consensus algorithm, to achieve lightweight public chain, after learning can develop golang website, crawler, Achieve lightweight blockchain
phase 3 4-week Ethereum source code analysis and smart contract DAPP development, master Ethereum core and smart contract development, as well as blockchain,
phase 4 4-week super ledger, bitcoin EOS, source code analysis and smart contract combat, master super ledger development, cat bitcoin, bifurcated EOS after learning, As well as the intelligent contract DAPP development
phase V 6-week project actual combat, five enterprise level projects, one year of blockchain project experience after learning
the popularity of the blockchain market has caused a large number of talents demand based on blockchain technical personnel, and the popularity of blockchain talents is rising at the speed of light. According to the "2018 blockchain high salary list" released by lagou.com, Tencent, Xiaomi, Suning, Jingdong and other domestic enterprise giants have released many high salary blockchain post demands, trying to explore blockchain related technologies and applications. It is also pointed out in the list that the demand for high salary jobs is mainly based on blockchain related technical jobs, among which Suning and Keda have been given the highest monthly salary of 100k
the huge market demand for technical talents will inevitably lead to the explosive emergence and growth of the whole blockchain training market. Most of the training modes can be divided into online training, traditional IT organization training, and offline short-term training camps, which mainly focus on high-end forms. However, in the process of the hot market evolution, there are also a variety of blockchain training chaos: lecturers' qualifications are watered down, and even the most basic names are not disclosed, the syllabus is opaque, and the teaching quality is shrinking, Unreasonable class arrangement and uneven training fees and so on
in the first stage, go language foundation and network concurrency will be completed in 4 weeks, and then the introctory go language will be learned.
in the second stage, go language will be used for practical web development, crawler development, cryptography, consensus algorithm, and lightweight public chain will be realized, and the website and crawler that can develop golang will be completed, and lightweight block chain will be realized.
in the third stage, Ethereum source code analysis and intelligent contract DAPP development will be completed in 4 weeks, After learning and mastering Ethereum core and smart contract development, as well as blockchain,
phase IV 4-week super ledger, bitcoin EOS, source code analysis and smart contract practice, after learning and mastering super ledger development, Shanzhai bitcoin, bifurcated EOS, and smart contract DAPP development
phase V 6-week project practice, five enterprise level projects, One year of blockchain project experience after learning