Seven elements of blockchain
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. It is essentially 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 the information of a bitcoin network transaction, Used to verify the validity of its information (anti-counterfeiting) and generate the next block
some areas where blockchain can be used can be as follows:
& ᦇ 9642; Smart contract; Securities trading; E-commerce; Internet of things; Social communication; File storage; Proof of existence; Authentication
&9642; Equity crowdfunding
we can compare the development of blockchain with the development of the Internet itself. In the future, something called finance Internet will be formed on the Internet. This thing is based on blockchain, and its precursor is bitcoin, that is, traditional finance starts from private chain and instry chain (LAN), bitcoin series starts from public chain (WAN), They all express the same concept - digital asset, and finally converge to an intermediate equilibrium point
The evolution mode ofblockchain is as follows:
& 9642; Blockchain 1.0 digital currency; Blockchain 2.0 digital assets and smart contracts; Blockchain 3.0: implementation of distributed applications in various instries
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
2. Blockchain is an innovative application mode of distributed data storage, point-to-point transmission, consensus mechanism, encryption algorithm and other computer technologies in the Internet era. In recent years, the development and application of blockchain is of great significance to technological innovation and instrial revolution. This experience introces the relevant knowledge of blockchain technology
3. Blockchain is a distributed ledger, which can contain financial and / or non-financial transactions. It can be replicated (distributed) on multiple systems in almost real time through peer-to-peer network. Each participant "owns" the same ledger and gets updated when adding any transaction. Each participant helps to determine the inherent "invariance" of all existing records, Using cryptography and digital signature to prove identity, authenticity and enforce read / write access, there is a mechanism that makes it difficult to change history, and it is easy to detect someone trying to change it.
1-contains a distributed database
2-distributed database is the physical carrier of blockchain, blockchain is the logical carrier of transaction, all core nodes should contain full copies of the blockchain data
3-blockchain serializes blocks according to time, And blockchain is the only body of the whole network transaction data
4-blockchain is only effective for addition, but not for other operations
5-public and 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, in the face of a certain amount of contradictions between different nodes, the data will not collapse
8-consensus process can solve the problem of double spending
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.
As we all know, blockchain is the proct of recent years, but the market for blockchain related courses can be said to be multifarious, fengmaolingjiao, each has its own merits, here, do a statistics, study, discuss and exchange together
mining mean? What did the miners do
10. What is the application of blockchain? What changes will blockchain bring
11. Blockchain will become the basic internet protocol, similar to TCP / IP and HTTP
12. What is Ethereum? Why is it the representative of blockchain 2.0? He is the founder of Ethereum and the real big man in the blockchain instry
14. What is a smart contract
15. What is Ethereum smart contract
V God said that the token system of Ethereum17. Machines need the certificate more than people
18. What is the standard of erc20 certificate
19. The Dao crowdfunding event and Ethereum bifurcation
20. How to design Tongzheng? How to express assets
21. Classification of token (list of categories)
22. Technology and components of Ethereum smart contract
23. Erc721 standard and encryption cat
24. Ethereum account (external account and contract account)
25. Four features of blockchain
26. What is blockchain 3.0 like
What is EOS? What is the difference between EOS, bitcoin and Ethereum The consensus mechanism and block generation of EOS29. Daniel laremo (BM): the main developer of EOS
30. A map to understand what EOS is
31. The "Impossible Triangle" of blockchain
32. What is the application of blockchain (decentralized application)
33. How to recover the stolen EOS key
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