Knowledge Encyclopedia blockchain

1. blockchain is a kind of chain data structure that combines data blocks in order according to the time sequence, and it can't be tampered and forged by cryptography. In a broad sense, blockchain technology is a new distributed infrastructure and computing paradigm, which uses blockchain data structure to verify and store data, uses distributed node consensus algorithm to generate and update data, uses cryptography to ensure the security of data transmission and access, and uses intelligent contract composed of automated script code to program and operate data
the underlying technologies of digital cryptocurrencies such as bitcoin, lightcoin, Puyin, and Ethereum are all blockchains, and they are just an application of blockchain.

2.

Blockchain is a kind of technology, which solves the core "trust" problem in the market economy and reces the trust cost between strangers to a very low level

there is one crucial thing in the market economy, which is "trust". Without trust, no deal can be established. When you go to LAICHANG to buy vegetables, if you don't believe that the pesticide content in vegetable is up to the standard, you won't trade with that dealer; If you buy a bottle of water in a small shop, the clerk will not sell you the water if he doesn't believe that the money you give is real

the traditional small-scale peasant economy is acquaintance economy, and the transaction scale is limited to people who are familiar with each other nearby. If an acquaintance deceives you, he will lose your social relationship and damage his reputation in the whole circle of acquaintances. We believe that acquaintances are less likely to cheat us than strangers

therefore, once we are beyond the scope of acquaintances, we need to use a high cost to identify whether a stranger will cheat me and how to avoid the risk of being cheated. This situation will hinder the transaction and restrict the transaction

in addition, different races, nationalities, cultures, religious beliefs and so on will naturally have this kind of trust problem

in the market economy, why can there be so many transactions between strangers? Because of the birth of a new mechanism to solve the problem of trust in strangers

so far, the most important mechanism to solve the trust problem is the "trust intermediary" organization and mode

as long as you and strangers trust a third-party organization, the trust problem between you can be solved through this third-party organization

this third-party organization, we call it trust intermediary. Both the government and the bank are trust intermediaries

you can sell the goods you have worked hard to proce to a stranger in exchange for a stack of RMB banknotes. It's because the credit of the note issuing bank and the guarantee of the authority of the government guarantee the currency value and effectiveness of the banknotes. Otherwise, sell things, in exchange for a few ordinary paper, who would like to

in the era of global village and Internet, the people who buy your things may be strangers who will not meet and thousands of miles away. Trust is lower, so Alipay assumes the role of trust intermediation. Buyers first pay the goods to Alipay's account. When they receive the goods, they confirm that they are OK, then they agree to sell the goods to the seller. Taobao and other e-commerce have been booming rapidly in just over ten years

trust intermediary is in a central position in the transaction system. All transactions should solve the trust problem through it

However, the cost of trust intermediary itself is often huge

as a trust intermediary, how much transaction tax does the government charge each year? What is the most profitable instry? Financial services. The annual profits of Alipay's ant suit are over ten billion. p> What does this mean? Both sides of the market actually pay a huge trust cost

if there is any way to cancel or greatly rece the trust cost, the transaction cost of the general public can be reced, and the profits can be greatly increased

so in the Internet era, blockchain technology is on the stage

it allows the trading party to get rid of the intermediary, solve the problem of trust among strangers, and greatly rece the cost of trust

the blockchain can be expanded on a large scale, the data is open and transparent, the data of each client is consistent, and even if some clients are destroyed, the data security will not be affected. These highly reliable technical features can solve the trust problem of strangers with low cost

this technology can be extended to all fields that can be digitized, such as digital currency, payment and clearing, digital bills, proof of rights and interests, credit reference, government services, medical records, etc

in the medium and long term, blockchain will be a revolutionary technology, which will bring about great social changes like the existing Internet, and has great investment value and money making opportunities

in the future, the companies that can combine blockchain with different scenarios to promote applications may be the next group of bat, the next Google, Microsoft and apple

as the first practical application of blockchain technology, bitcoin has been widely accepted and used all over the world. Millions of users and tens of thousands of merchants have accepted the payment of bitcoin as a digital currency, and the exchange value of bitcoin as a currency is growing. Even e to the consensus that the total amount is fixed and the long-term value is bullish, bitcoin has become a hedge asset similar to gold, and the price has skyrocketed

3.

1. Application of blockchain technology in the banking instry the biggest feature of blockchain technology is decentralization, which will rece a lot of costs for the banking instry. The development of digital currency will make it possible for banks to realize real-time digital transactions. For example, in bill transaction, bank bill transaction always relies on the third party to realize the transfer of valuable documents. Even in electronic bill transaction,

also needs to be authenticated through the information of central bank ECDs system. The blockchain technology can realize the point-to-point value transmission, which no longer needs centralized system control. This not only speeds up the bill transmission speed, but also reces the mistakes caused by human factors. The rection of process will naturally rece the demand of the bank for personnel and save the labor cost of the bank

2, the application of blockchain technology in the insurance instry

blockchain technology also has incomparable advantages in the insurance instry. From the perspective of data management, the application of blockchain technology can effectively improve the risk management and control ability of insurance companies, including the risk supervision of insurance companies and the risk management of policyholders

the application of blockchain technology in the insurance instry can strengthen the internal risk supervision of insurance companies. Blockchain technology can record the daily operation process of insurance company on the node, realize the in-process control of the company's capital flow, investment situation, compensation amount and other business, and improve the company's risk management and control ability

3. Application of blockchain technology in the securities instry

4, blockchain technology and financial infrastructure

blockchain technology is a decentralized mechanism for value exchange, which will lead to earth shaking changes in the existing financial infrastructure characterized by centralization

5. Application of blockchain technology in supply chain, It has become an effective guarantee for enterprise bank's loan credit, financing credit and transaction credit

4. The term blockchain comes from bitcoin, and it is also the underlying technology of bitcoin. In short, it is an account book with incentive system. In an open transaction, everyone can keep an account according to their computing power, keep the account book updated and the transaction going on, and those who successfully keep an account will be rewarded (bitcoin), Through such self motivation, the operation mechanism that does not rely on any company or organization is called blockchain

5. The key to the implementation of blockchain technology in the real economy should be based on the pain points of an instry, with foundation and application scenarios, rather than creating a new application scenario for human. In fact, issuing indivial currency and upgrading the main chain can not be called landing. The real landing should be integrated with the real economy, creating value-added, breaking away from the virtual to the real, serving the real economy, and improving the efficiency of all kinds of social activities
then, how to judge whether blockchain technology is reliable depends on two main points
first, there should be a real application scenario. No matter how small the application scenario is, it must be valuable
whether blockchain technology can finally be implemented depends on many complex factors, and one of the key points is the application scenario. To find the corresponding application scenario, we should start from the technical characteristics of blockchain itself. Blockchain technology can provide decentralized, tamper proof, safe and reliable characteristic guarantee without introcing third-party intermediaries
Second, the application of blockchain technology should be able to solve problems, not manufacturing problems
with real application scenarios, it also hit the pain points in the instry, but these are not enough to make blockchain technology truly land in the real economy and realize the integration with the real economy. Because the most critical point depends on whether the blockchain technology is applied to solve the problem
with the application of blockchain technology and the assistance of some Internet of things devices, investors can query the real-time and dynamic data of the project at any time, and can directly monitor the progress of the project in different places even without leaving home
using blockchain technology to solve the original difficult problems, combined with the real application scenarios, the implementation of blockchain technology in the real economy has become a natural thing.

6. Bitcoin is a "digital currency" based on blockchain technology. In 2013, the central bank made it clear that bitcoin, as a specific virtual commodity, does not have the same legal status as currency and cannot and should not be used as currency in the market. The reason why bitcoin has become the "accomplice" of hackers this time lies in the characteristics of bitcoin: anonymity and difficulty in supervision

compared with other ways, using bitcoin to remit money is much more "secret". Normal cross-border remittance will go through the examination of exchange control institutions at all levels, and the transaction records will be recorded by banks and other parties. Transactions exceeding a certain amount should be reported to relevant departments to prevent money laundering and other violations. Bitcoin, with the characteristics of globalization, is usually used as a tool for cross-border payment and remittance. As a kind of network encryption virtual currency, bitcoin has the characteristics of decentralization and anonymity,
capital flow is not easy to track, and it is easier to hide identity
wannacry blackmail virus prevention method:
1. Install the latest security patch for the computer. Microsoft has released patch ms17-010 to fix the system vulnerability of "eternal blue" attack. Please install this security patch as soon as possible; For Windows XP, 2003 and other machines that Microsoft no longer provides security updates, we can use 360 "NSA Arsenal immunity tool" to detect whether there are vulnerabilities in the system, and close the ports affected by the vulnerabilities, so as to avoid being infringed by blackmail software and other viruses
2. Close ports 445, 135, 137, 138 and 139, and close network sharing
3. Strengthen the awareness of network security: don't click the unknown link, don't download the unknown file, don't open the unknown email...
4. Back up the important files in your computer to the mobile hard disk and U disk as soon as possible (regularly in the future), and save the disk offline after the backup
5. It is recommended that users who are still using Windows XP and windows 2003 should upgrade to Windows 7 / windows 10 or windows 2008 / 2012 / 2016 as soon as possible.

7. There are many basic definitions of blockchain. Here, I will analyze the opinions of different schools, and use a more understandable explanation:
blockchain English Name: blockchain, also known as block chain, is a kind of chain data structure that combines data blocks in chronological order, It is a distributed account book that can not be tampered with and forged by means of cryptography
blockchain is essentially a distributed database, which is a series of data blocks generated by using cryptographic methods. Each data block contains the information of a network transaction, which is used to verify the validity of its information (anti-counterfeiting) and generate the next block
2. Working principle
the core potential of blockchain lies in the characteristics of distributed database and how to help transparency, security and efficiency
in the past, institutions used a central database to support transaction processes and calculations. The control of the database is in the hands of its owner, who manages the access and update rights to the database, which limits the transparency and scalability, and makes it difficult for outsiders to ensure that the data records are not manipulated
at the same time, e to technical limitations, distributed database is basically impossible to achieve. But with the development of software, communication and encryption technology, it is possible to build a distributed database across organizations. Blockchain has graally emerged
3. Core idea
the basic idea of blockchain is to establish a network-based public ledger (data block), each block contains the information of a network transaction. All the participating users in the network work together to keep accounts and check accounts. All the data are open and transparent, and can be used to verify the effectiveness of the information. In this way, the authenticity and non tamperability of information can be guaranteed at the technical level without the central server as the trust intermediary.