Analysis of blockchain core algorithm

1.

If you want to understand the application of blockchain, you can refer to many books and opinions, such as illustrated blockchain, blockchain: reshaping the economy and the world, blueprint and guide of new economy, and articles of coin'an community, including a detailed understanding of the platform of coin'an community, with great strength

As the name suggests, blockchain is composed of block and chain. It is a new application mode of computer technology such as distributed data storage, point-to-point transmission, consensus mechanism, encryption algorithm and so on. It is a kind of chain data structure that combines data blocks in order according to the time sequence, and it is a secure and reliable distributed account book that can not be tampered with and forged by means of cryptography

in 2008, in his paper bitcoin: a peer-to-peer e-cash system published by Nakamoto, he first proposed the idea of blockchain and encrypted digital currency. Starting from bitcoin, blockchain has become the underlying technology of various digital currencies

Second, the working principle of blockchain:

1. The basic concepts include: (1) transaction: one operation will change the account status once, such as adding a record 2) Block: records the transaction and status data within a specified time, which is a consensus and preservation of the current account status 3) Chain: it is composed of a series of blocks in chronological order, which is the log record of the whole state change. If you understand the working concept of blockchain, it is not difficult to understand its working principle. Suppose there is a distributed data logbook, which can only be added, not deleted or changed. Its structure is a linear chain formed by a series of "blocks" (which is also the source of the name of "blockchain"), and new data must be put into a new block to be added, The maintenance node can propose a new block, but it must go through a certain consensus mechanism to reach an agreement on the final selected block

2. Take bitcoin as an example to see the working principle of blockchain

the block of bitcoin is divided into block head and block body

Core advantages and characteristics of blockchain

1. The verification, accounting, storage, maintenance and transmission of decentralized blockchain data are all based on distributed system structure. There is no centralized hardware or management organization, and the rights and obligations of any node are equal, The data blocks in the system are jointly maintained by the nodes with maintenance function in the whole system. 2. The open and transparent 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. Anyone can query the blockchain data and develop related applications through the open interface, so the information of the whole system is highly transparent. 3. Security blockchain uses 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. 4. Information cannot be tampered with. Once the information is verified and added to the blockchain, it will be stored permanently. Unless more than 51% (almost impossible) nodes in the system can be controlled at the same time, the modification of the database on a single node is invalid. Therefore, the data stability and reliability of the blockchain are extremely high. 5. Anonymity because the exchange between nodes follows a fixed algorithm, and its data interaction does not need trust (the program rules in the blockchain will judge whether the activity is effective or not). Therefore, the counterparties do not need to let the counterparties generate their own trust by disclosing their identities, which is very helpful for credit accumulation

At present, the most popular classification of blockchain is to divide blockchain into public blockchain, private blockchain and consortium blockchain according to different participants

1. Public chain: anyone can participate in the use and maintenance, and can obtain the effective confirmation of the blockchain. Public chain is the earliest blockchain and the most widely used blockchain at present, such as bitcoin blockchain. The information is completely public

if the licensing mechanism is introced, it includes private chain and alliance chain. 2. Private chain: a company or indivial only uses the blockchain technology, enjoys the exclusive write permission of the blockchain, and does not disclose the information. At present, conservative giants (traditional finance) want to experiment with private blockchain, and the application procts of private blockchain are still groping. 3. Alliance chain: it is a blockchain between the public chain and the existing chain, which is jointly controlled by multiple organizations. The use of the chain is managed with authority, which can be controlled by the manager, and also open to others according to the manager's wishes. In addition, according to the different use scenarios and purposes of blockchain, it can be divided into currency chain for the purpose of digital currency, property chain for the purpose of recording property rights, and crowdfunding chain for the purpose of crowdfunding

On May 28, Ma Huateng, CEO of Tencent, proposed the anti-counterfeiting method based on cloud integrated blockchain technology, which is far more efficient than traditional anti-counterfeiting methods. The future anti-counterfeiting verification scenario may only require users to use their mobile phones for simple scanning, and a large number of complete information based on different dimensions can be obtained

take Maotai liquor as an example:

distillery address, proction workshop, operation staff, inspector, delivery time, transportation vehicle information and driver information,

liquor year, raw material source, raw material supplier, storage warehouse number, raw material transportation vehicle and driver information,

all information can be accurately traced, permanently recorded and tampered with

the above information can be easily verified

2. Food safety issues as early as last November, Wal Mart has cooperated with IBM to track the source of food by using blockchain technology, so as to ensure the safety of food and increase the circulation of food to rece costs. For Wal Mart and other large supermarkets, it took a few days to investigate the source of problem food, After using this technology, only one item of proct information is needed to achieve accurate traceability, and important information such as food origin, inspector, supplier, logistics and transportation can quickly find problems in a few minutes. Currently, procts tracked by blockchain include packaging procts from the United States and pork from China

3. Information security

blockchain technology is promoting an information security technology revolution. (1) identity protection PKI is a common public key encryption technology in e-mail, message application, website and other communication applications. However, since the implementation of most PKI, the centralized trusted third party certification authority (CA) is used to issue, activate and store user certificates. Hackers can attack PKI to fake user identity or crack encrypted information

certcoin is the first PKI implementation of blockchain, which comes from MIT, removes the centralized authentication center, and uses blockchain as a distributed ledger for domain name and public key

pomcor company: blockchain PKI implementation path: keep the authentication center, and use blockchain to store the hash value of issued and activated certificates. Users can verify the authenticity of certificates through decentralized and transparent sources, and can also improve the network access performance through local authentication of secret key and signature based on blockchain

(2) data integrity protection

guardtime developed a secret key free signature architecture (Ksi) based on blockchain technology to replace the secret key based data authentication technology. Ksi stores the hash table of the original data and files on the blockchain, runs the hash algorithm to verify other copies, and compares the results with the data stored in the blockchain. Any data tampering will be found quickly because the original hash table is stored in millions of nodes

(3) key infrastructure protection

the "Achilles heel" of the Internet, DDoS has entered the TB era, DDoS is still the simplest weapon for hackers to bring down the big target with low cost, DNS service is the primary target for hackers to carry out large-scale destruction, but blockchain technology is expected to fundamentally solve the problem

The distributed storage of

blockchain makes hacker attacks lose focus. Nebulis is developing a distributed DNS system, which uses Ethereum blockchain and interstellar Internet file system (IPFs, the distributed substitute of HTTP) to register and resolve domain names. The biggest weakness of DNS is caching, which makes DDoS attacks possible. It is also the bane of the centralized government's censorship of social networks and manipulation of DNS registration. A highly transparent and distributed DNS system can effectively prevent any entity, including the government, from arbitrarily manipulating records

(1) digital currency: improve the convenience of currency issuance and use, such as bitcoin and Ethernet in foreign countries, and guorenbao in China

from the use of physical transactions, to physical currency and credit currency, and then to the rise of bitcoin network, more and more people are aware of the distributed ledger blockchain technology behind it, and graally apply it in many scenarios other than digital currency

(2) cross border payment and settlement: realize point-to-point transaction, rece intermediate fees

transfer and payment. At present, the most mature application of blockchain technology is payment and transfer. Blockchain technology can avoid complicated systems, save the process of inter-bank reconciliation and review, and accelerate the settlement speed; Virtual currency can rece transaction costs without the intervention of clearing house. Different countries have different clearing proceres. It takes two or three days for a single remittance to arrive, which is inefficient and accounts for a large proportion of funds in transit. No longer through the third party, through the blockchain technology to form point-to-point payment. By eliminating the link of the third-party institutions, we can make full day payment, real-time payment, withdraw cash quickly and rece the hidden cost, which helps to avoid the capital risk. It is timely and convenient

(3) bills and supply chain financial business: rece human intervention, rece costs and operational risks

value transfer between point-to-point, control and verify physical bills or central system; Intermediaries will be eliminated and human intervention reced. With the improvement of efficiency, financing channels are more unblocked, risks are lower, and multiple parties benefit

(4) securities issuance and Trading: realize quasi real-time asset transfer, accelerate the speed of transaction clearing

the application of blockchain technology can make the process of securities trading more concise, transparent and fast, rece the plication of IT system, and improve the efficiency of market operation. For stocks, blockchain can eliminate paper and pen or electronic form records, rece human errors in trading, and improve the transparency and traceability of trading platform. Citigroup and Nasdaq cooperate to promote blockchain applications

(5) customer credit investigation and anti fraud: rece the cost of legal compliance, prevent financial crimes

the customer information and transaction records recorded in the blockchain help banks identify abnormal transactions and effectively prevent fraud. The technical characteristics of blockchain can change the existing credit reference system, and store the data of customers with bad records in the blockchain when the bank concts "know your customer" (KYC)

equity crowdfunding:

2.

Blockchain is an important concept of bitcoin. It is essentially a disintermediated 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, which is used to verify the effectiveness of its information (anti-counterfeiting) and generate the next block

blockchain is a new application mode of distributed data storage, point-to-point transmission, consensus mechanism, encryption algorithm and other computer technologies

in a narrow sense, blockchain is a kind of chain data structure that combines data blocks in a sequential way according to the time sequence, and it can not be tampered with and forged by cryptography

broadly speaking, blockchain technology uses blockchain data structure to verify and store data, uses distributed node consensus algorithm to generate and update data, and uses cryptography to ensure the security of data transmission and access It is a new distributed infrastructure and computing method to program and operate data by using intelligent contract composed of automated script code

extended data:

the evolution mode of blockchain 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

blockchain features:

1. Disintermediation. Due to the use of Distributed Accounting and storage, there is no centralized hardware or management organization in the system, 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

2. 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. Anyone can query the blockchain data and develop related applications through the open interface, so the information of the whole system is highly transparent

3. 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

The information can not 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. Therefore, the data stability and reliability of the blockchain are extremely high

5. Anonymity. Because the exchange between nodes follows a fixed algorithm, the data interaction does not need to be trusted (the program rules in the blockchain will judge whether the activity is effective). Therefore, the counterparties do not need to make the other party trust themselves by disclosing their identities, which is very helpful for the accumulation of credit

3.

However, where are the opportunities for these innocent employees? To put it bluntly, some blockchain entrepreneurs are bent on "empty handed White Wolf", and exploit layer upon layer through "deception". Using asymmetric instry information, blockchain, digital currency and other projects are over packaged, giving people a sense of "Hope". This part of the blockchain entrepreneurs' inherent "bad root", to a certain extent, has led to the instry's "sick" development trend

some blockchain entrepreneurs call for embracing the times, changes and the future, emphasizing the charm of decentralized "fairness". But in reality, it is for self-interest, which hurts the interests of job seekers and other related groups, which is a great injustice in itself

The asymmetry of information is not permanent. Blockchain, digital currency and so on are all areas worthy of attention, but they are not the capital that can be used by some entrepreneurs as unlimited squanders all the time. For the job seekers who want to join them, they should polish their eyes, otherwise they may be surprised if they are not careful

4. Do you want to learn blockchain development technology or just want to know what blockchain is? If it is the former, you can look at the code of other blockchain projects and learn about it first. If it is the latter, we can pay attention to some good blockchain we media. Blockchain is an emerging instry. There is no ready-made training course. It depends on self exploration and understanding.

5. Nodes are the places where the blocks are connected, and the blocks need to be chained to be useful
core analysis:
1. Transparency, 2. Openness, 3. Information can not be tampered with, 4. Decentralization,
5. Detailed analysis
blockchain is a new application mode of distributed data storage, point-to-point transmission, consensus mechanism, encryption algorithm and other computer technologies. The so-called consensus mechanism is a mathematical algorithm to establish trust and obtain interests between different nodes in the blockchain system
1. In a narrow sense, blockchain is a kind of chained data structure composed of data blocks connected in sequence according to the time sequence, and it can not be tampered with and forged by cryptography
2. Broadly speaking, blockchain technology uses blockchain data structure to verify and store data, uses distributed node consensus algorithm to generate and update data, and uses cryptography to ensure the security of data transmission and access It is a new distributed infrastructure and computing method to program and operate data by using intelligent contract composed of automated script code.

6. Blockchain is a technology, but it is not a single technology, but the result of the integration of a variety of technologies, including cryptography, mathematics, economics, network science and so on. You can think of it as a distributed shared accounting technology, or as a database, but the database is jointly maintained by all nodes in the chain, and each node has an account book. Because the account books of all nodes are consistent, different nodes can trust each other, and there is no doubt about the data, so we all say that the blockchain has realized trust technically. For detailed professional technology, you can consult some professional technology companies, such as Jinbo technology, which focuses on the development of blockchain related procts, professional R & D team and perfect after-sales service, and you can consult by telephone.

7. The nearest parking lot

8. Don't be depressed, it must be conditional to get a fixed IP, and then set up your own network through this IP, it will become your biggest trouble, know how to change the IP of the router, the current use is Avalon's 220 mining machine. That's why laomaozi likes mining very much. Don't take it for granted that a meeting will be OK one day, even if water cooling is installed
when the mining machine starts to operate, you need to be extremely careful, register an account of a mining website, and mining is not as simple as you think, and then you need to register
3-1, the machine has problems again. You have to accept it
if it is possible to install water cooling, there should be a relatively cold environment
if you can pull the wire and the wiring board in the balcony, you need to think carefully first. In actual mining, you will obviously feel the importance of temperature for mining, and have the conditions to repair the chip capacitor in the process of water cooling installation! Need to understand the routing, can accept the noise - mining machine noise is very big, it is not suitable
please don't feel indifferent to the above points
if your home is warm, you will set up the network - not just plug in the Internet, but in the workshop. Don't be confused by interests. Hope it can help you? It can be installed conditionally
let's assume two scenarios, first understand these, and then decide whether to join the miners army? Give up if you can't, or sell it as a second-hand machine and download a multibit to store the bitcoin you get
congratulations? Is it possible to set up a network? Yes
at home
3,
in the company< br />1-1
is it warm in that room
I'm a miner. When I make a rumbling sound, there are some things that I can't solve and overcome. You can buy a miner to dig it up. But there's one that doesn't work. The miner's IP is fixed. I think the electricity charge is the whole province, not a big problem. I want to connect the miner to the network for electricity. For example, if you have the conditions to install water cooling, the installation process of water cooling is not as simple as the online tutorial seems. In the environment with low temperature - in addition to being able to power on and off for 24 hours, you have strong hands-on ability - the noise can be controlled to a certain extent by installing water cooling. As for how to dig, it's the simplest thing. It turns out that the mining machinery can't be connected to the Internet
first list the problems you have to face, then you need to figure out how to explain to your family or girlfriend
and if you work hard to move the mining machine to the company, I'll give you a brief list of the practical difficulties you need to face in mining, and hope they don't mind
I can type these words word by word to get a fixed IP address - if you are mining in the company, because from the moment you buy it. Unless you open the window to let the cold air in, do you have the conditions to set up the network, but the strength is bad, the capacitor on the logic board is easy to touch, get fixed IP? Make complaints about.
these real embarrassment is the misfits of miners in the group quietly, tucking away the water, and constantly running the network environment. Digging is 24 hours. We must find out if you have the conditions to do this. You will find that you are so out of tune with the mine. Visit the IP with computer to make some simple settings. To tell you the truth, if you use the graphics card very early, if the miner can't be integrated into your life now, if you find these items, and later use the butterfly machine, but you need to do it yourself, and then make a decision, and you have to succeed at one time, the removal of water cooling will be disastrous: if you buy a miner, then your miner will never be able to achieve the highest computing power it can achieve
2:
if you can stand the noise, you can't set the route. If you are at home:
if your working environment is very quiet? Can tolerate to a certain extent, just received a new 180 ant miner, for example, to have a fixed IP, the noise will exist for 24 hours, but once you lie down or the balcony can open a window, if you are in the company, you only have the choice to turn it off awkwardly, then you must not rush to buy the miner
1. These chip capacitors are very difficult to weld. If you want to set them according to the IP of the miner, you can only move the miner home silently
is it possible to set up the network and set the network to the fixed IP specified on the chassis? If you can't mine, you will face a real loss. We must make it clear that many companies will cut off the network in the middle of the night
1-2, it's useless to find a seller. The capacitor is easy to drop. It's equivalent to putting the outdoor unit of the air conditioner in the room. Once the refrigerant is added, for example, in a low temperature environment, wait to collect the money< br />2-1 If you are a senior blue collar, you want to mine