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Arab blockchain
Publish: 2021-04-27 09:57:31
1.
Who is Nakamoto? Why are people so curious about him? This person, who calls himself Nakamoto Tsung, said that he lost his bitcoin, not one or two, but a lot. What does 980000 bitcoins mean
so we should take a calm attitude towards bitcoin
so far, no one knows the true face of this Nakamoto. Even his so-called 980000 bitcoins are skeptical
because, generally, people who are really rich are disdainful of showing off their wealth
2. In order to understand the technical principle of bitcoin, we need to understand two important cryptographic techniques: hash code: it converts a long string into a fixed length string, and its conversion is irreversible, that is, it is impossible to guess the original string from hash code. Sha256 is mainly used in bitcoin protocol
public key system: corresponds to a public key and a private key, keeps the private key in the application and publishes the public key. When Party A transmits information to Party B, it can use Party A's private key to encrypt the information, and Party B can use Party A's public key to decrypt the information, so as to ensure that the third party cannot impersonate Party A to send the information; At the same time, when Party A transmits information to Party B, it is encrypted with Party B's public key and sent to Party B, and then Party B decrypts it with his own private key, so as to ensure that the third party cannot eavesdrop on the communication between the two people. RSA is the most common public key system, but the lliptic curve digital signature algorithm is used in bitcoin protocol. What's the difference between cash and bank account? Bitcoin is an electronic currency in BTC. In this article, it is also used to refer to the whole bitcoin system. Like opening an account in a bank, the corresponding concept in bitcoin is address. Everyone can have one or more bitcoin addresses, which are used to pay and collect money. Each address is a string that starts with 1. For example, I have two bitcoin accounts, and. A bitcoin account is uniquely determined by a pair of public key and private key. To save the account, you only need to save the private key file. Unlike bank accounts, banks keep all transaction records and maintain the book balance of each account, while bitcoin's transaction records are jointly maintained by the whole P2P network through a pre agreed protocol. How much money is in my account address? Although the current account balance can be seen by bitcoin software, unlike banks, there is no place to maintain the book balance of each address. It can only calculate the account balance in real time through all historical transactions. How do I pay? When I pay from address a to address B of the other party, the payment amount is e. at this time, both parties will announce the transaction information to each network node, telling address a to pay to address B, and the payment amount is e. In order to prevent the third party from forging the transaction information, the transaction information will be encrypted with the private key of address A. at this time, the network node receiving the transaction information can use the public key of address a to verify that the transaction information is indeed sent by address a. Of course, trading software will help us do these things, we just need to input the relevant parameters in the software. What will the network node do after receiving the transaction information? This is the most important part of the bitcoin system, which needs to be elaborated. For the sake of simplicity, only bitcoin protocol has been implemented. In the current version, each network node will save all transaction information synchronously. There are two kinds of transaction information in history, one is & quot; Verified & quot; The transaction information, that is, the verified transaction information, is stored in a series of "blocks". Each & quot; block" Is the previous & quot; bock" The ID of each block is the hash code of the hash code of the block and the new transaction information (see an actual block). The other category refers to those who also & quot; Unverified & quot; The transaction information just paid above belongs to this category. When a network node receives new unverified transaction information (possibly more than one), it can calculate the book balance of each address at that time because the node keeps all the transaction information in history, so it can calculate whether the transaction information is valid, that is, whether there is enough balance in the payment account. After eliminating the invalid transaction information, it first takes out the last & quot; block" Then, the unverified transaction information is combined with the ID, and a verification code is added to form a new "block". It needs a lot of calculation to build a new block, because it needs to calculate the verification code, so that the above combination becomes a block, that is, the first several bits of the hash code of the block are 1. At present, the first 13 bits need to be 1 (generally, the specific method is uncertain), which means that if the block is generated by enumeration method, the average number of enumerations is 16 ^ 13. Using CPU resources to generate a block is called "gold mining", because the proction of the block will get a certain reward, and the reward information has been included in the block. When a network node generates a new block, it will broadcast to other network nodes. However, this network block may not be accepted by the network, because it is possible that other network nodes have proced the block earlier. Only the earliest block or the block with the largest number of subsequent blocks is valid, and the remaining blocks are no longer used as the initial blocks of the next block. How does the other party confirm that the payment is successful? When the payment information is distributed to the network node, the network node begins to calculate whether the transaction is valid (that is, whether the account balance is enough to pay), and attempts to generate blocks containing the transaction information. When six blocks (one direct block and five subsequent blocks) contain the transaction information, the transaction information is considered "verified", so that the transaction is formally confirmed, and the other party can confirm the successful payment. A possible problem is that I will pay the balance of address a to address B, and at the same time pay to address C. If I only verify that the single comparison transaction is valid. At this point, my way of cheating is to generate six blocks including B to B and six blocks including C to C before the truth is revealed. Because I need a very long CPU time to generate a block, compared with the whole network, the probability of my cheating success is very small. What is the motivation of network nodes to proce blocks? As can be seen from the above description, in order to make the transaction information effective, the network node needs to generate 1 and 5 subsequent blocks to contain the transaction information, and such block generation is very CPU intensive. How to let other network nodes help to proce blocks as soon as possible? The answer is very simple. The agreement stipulates that BTC will be rewarded for the address where the block is proced, as well as the Commission promised by both parties. At present, the reward for procing a block is 50btc, which will be halved every four years in the future. For example, the reward will be 25btc from 2013 to 2016. Is the transaction anonymous? Yes, and No. All bitcoin transactions are visible. We can check all transaction records of each account, such as mine. But what's different from the banking monetary system is that everyone's account itself is anonymous, and everyone can open many accounts. In general, anonymity is not as good as it claims. But bitcoin has another advantage in doing black market trading: it can't be frozen. Even if the police trace a bitcoin address, there is nothing they can do unless they trace the computer used by the exchange based on the Internet address. How to ensure that bitcoin does not depreciate? Generally speaking, in the case of equivalent trading activities, the value of money is inversely proportional to the amount of money issued. Unlike the traditional money market, the central bank can determine the amount of money issued. Bitcoin does not have a central issuing institution. Only by procing blocks can we get a certain amount of BTC currency. Therefore, bitcoin's new amount of money depends on: 1. The speed of procing blocks: bitcoin's agreement stipulates that the difficulty of procing blocks is fixed at an average of 2016 every two weeks, about 10 minutes. Moore's law of doubling CPU speed every 18 months will not speed up the proction of block. 2. The number of rewards for block proction: at present, 50 BTC is awarded for each block proced, which is halved every four years. In 2013, 25 BTC is awarded, and in 2017, 12.5 BTC is awarded. Considering the above two factors, bitcoin's currency issuing speed is not controlled by any single node in the network. Its protocol makes the currency stock known in advance, and the maximum stock is only 21 million BTC
public key system: corresponds to a public key and a private key, keeps the private key in the application and publishes the public key. When Party A transmits information to Party B, it can use Party A's private key to encrypt the information, and Party B can use Party A's public key to decrypt the information, so as to ensure that the third party cannot impersonate Party A to send the information; At the same time, when Party A transmits information to Party B, it is encrypted with Party B's public key and sent to Party B, and then Party B decrypts it with his own private key, so as to ensure that the third party cannot eavesdrop on the communication between the two people. RSA is the most common public key system, but the lliptic curve digital signature algorithm is used in bitcoin protocol. What's the difference between cash and bank account? Bitcoin is an electronic currency in BTC. In this article, it is also used to refer to the whole bitcoin system. Like opening an account in a bank, the corresponding concept in bitcoin is address. Everyone can have one or more bitcoin addresses, which are used to pay and collect money. Each address is a string that starts with 1. For example, I have two bitcoin accounts, and. A bitcoin account is uniquely determined by a pair of public key and private key. To save the account, you only need to save the private key file. Unlike bank accounts, banks keep all transaction records and maintain the book balance of each account, while bitcoin's transaction records are jointly maintained by the whole P2P network through a pre agreed protocol. How much money is in my account address? Although the current account balance can be seen by bitcoin software, unlike banks, there is no place to maintain the book balance of each address. It can only calculate the account balance in real time through all historical transactions. How do I pay? When I pay from address a to address B of the other party, the payment amount is e. at this time, both parties will announce the transaction information to each network node, telling address a to pay to address B, and the payment amount is e. In order to prevent the third party from forging the transaction information, the transaction information will be encrypted with the private key of address A. at this time, the network node receiving the transaction information can use the public key of address a to verify that the transaction information is indeed sent by address a. Of course, trading software will help us do these things, we just need to input the relevant parameters in the software. What will the network node do after receiving the transaction information? This is the most important part of the bitcoin system, which needs to be elaborated. For the sake of simplicity, only bitcoin protocol has been implemented. In the current version, each network node will save all transaction information synchronously. There are two kinds of transaction information in history, one is & quot; Verified & quot; The transaction information, that is, the verified transaction information, is stored in a series of "blocks". Each & quot; block" Is the previous & quot; bock" The ID of each block is the hash code of the hash code of the block and the new transaction information (see an actual block). The other category refers to those who also & quot; Unverified & quot; The transaction information just paid above belongs to this category. When a network node receives new unverified transaction information (possibly more than one), it can calculate the book balance of each address at that time because the node keeps all the transaction information in history, so it can calculate whether the transaction information is valid, that is, whether there is enough balance in the payment account. After eliminating the invalid transaction information, it first takes out the last & quot; block" Then, the unverified transaction information is combined with the ID, and a verification code is added to form a new "block". It needs a lot of calculation to build a new block, because it needs to calculate the verification code, so that the above combination becomes a block, that is, the first several bits of the hash code of the block are 1. At present, the first 13 bits need to be 1 (generally, the specific method is uncertain), which means that if the block is generated by enumeration method, the average number of enumerations is 16 ^ 13. Using CPU resources to generate a block is called "gold mining", because the proction of the block will get a certain reward, and the reward information has been included in the block. When a network node generates a new block, it will broadcast to other network nodes. However, this network block may not be accepted by the network, because it is possible that other network nodes have proced the block earlier. Only the earliest block or the block with the largest number of subsequent blocks is valid, and the remaining blocks are no longer used as the initial blocks of the next block. How does the other party confirm that the payment is successful? When the payment information is distributed to the network node, the network node begins to calculate whether the transaction is valid (that is, whether the account balance is enough to pay), and attempts to generate blocks containing the transaction information. When six blocks (one direct block and five subsequent blocks) contain the transaction information, the transaction information is considered "verified", so that the transaction is formally confirmed, and the other party can confirm the successful payment. A possible problem is that I will pay the balance of address a to address B, and at the same time pay to address C. If I only verify that the single comparison transaction is valid. At this point, my way of cheating is to generate six blocks including B to B and six blocks including C to C before the truth is revealed. Because I need a very long CPU time to generate a block, compared with the whole network, the probability of my cheating success is very small. What is the motivation of network nodes to proce blocks? As can be seen from the above description, in order to make the transaction information effective, the network node needs to generate 1 and 5 subsequent blocks to contain the transaction information, and such block generation is very CPU intensive. How to let other network nodes help to proce blocks as soon as possible? The answer is very simple. The agreement stipulates that BTC will be rewarded for the address where the block is proced, as well as the Commission promised by both parties. At present, the reward for procing a block is 50btc, which will be halved every four years in the future. For example, the reward will be 25btc from 2013 to 2016. Is the transaction anonymous? Yes, and No. All bitcoin transactions are visible. We can check all transaction records of each account, such as mine. But what's different from the banking monetary system is that everyone's account itself is anonymous, and everyone can open many accounts. In general, anonymity is not as good as it claims. But bitcoin has another advantage in doing black market trading: it can't be frozen. Even if the police trace a bitcoin address, there is nothing they can do unless they trace the computer used by the exchange based on the Internet address. How to ensure that bitcoin does not depreciate? Generally speaking, in the case of equivalent trading activities, the value of money is inversely proportional to the amount of money issued. Unlike the traditional money market, the central bank can determine the amount of money issued. Bitcoin does not have a central issuing institution. Only by procing blocks can we get a certain amount of BTC currency. Therefore, bitcoin's new amount of money depends on: 1. The speed of procing blocks: bitcoin's agreement stipulates that the difficulty of procing blocks is fixed at an average of 2016 every two weeks, about 10 minutes. Moore's law of doubling CPU speed every 18 months will not speed up the proction of block. 2. The number of rewards for block proction: at present, 50 BTC is awarded for each block proced, which is halved every four years. In 2013, 25 BTC is awarded, and in 2017, 12.5 BTC is awarded. Considering the above two factors, bitcoin's currency issuing speed is not controlled by any single node in the network. Its protocol makes the currency stock known in advance, and the maximum stock is only 21 million BTC
3. Generating the pseudo exhaustive one-way mapping list does not change its security
4. The communication app of blockchain can directly send and receive token red packets and flash cash transactions
5. This is actually very simple. This should be a Russian money.
6. Digital economy is closely related to your life
in addition to promoting the transformation and upgrading of the real economy, the development of digital economy also plays an important role in improving people's livelihood and enhancing social welfare. According to the survey of 34 OECD member countries concted by the world economic forum, every 10 points increase in the level of digitalization can promote the OECD happiness index to rise by about 1.3 points. For example, through a series of innovations, the government can provide a large number of integrated and innovative services for the public< The official account of WeChat, br / >, has basically formed the application system of WeChat public number, which is composed of ministries and commissions and local departments at all levels. It has achieved full coverage of government functions such as public security, tourism, food and drug administration, party and government, transportation, ecation, medical treatment, human rights protection, justice, foreign trade and so on. In many areas of government affairs and people's livelihood, wechat service has become the norm
the digital economy also actively expands the field of life and forms a new format of convenient services. Water and electricity payment allows users to enjoy fingertip life payment at home; Cooperation in catering, housekeeping, logistics, ecation, medical care, tourism, hotel, parking, community and other fields will form intelligent solutions and develop a new o2o service mode
don't understand digital economy? You will become a "new illiterate" in the new era.
while enjoying the benefits of digital economy, workers are also suffering from the al skills challenge brought by it digital skills and professional skills. However, there is a widespread shortage of digital technology talents in various countries, and 40% of companies say it is difficult to find the data analysis talents they need. Therefore, high digital literacy has become an important factor for workers to win in the job market
for consumers, if they do not have basic digital literacy, they will not be able to correctly use information and digital procts and services, and eventually become "illiterate" in the digital era. Therefore, digital literacy is regarded by the United Nations as a basic human right in the digital era and a basic ability as important as listening, speaking, reading and writing. Improving digital literacy is not only concive to digital consumption, but also concive to digital proction. It is one of the key elements and important foundations for the development of digital economy
four problems of digital economy
although digital economy is the general trend, it also faces some obstacles to be overcome in the process of development
1. The problem of digital divide is still serious
at present, there are still 4 billion people in the world who can not access the Internet, and there is a lack of digital skills in all countries. According to the statistics of the European Union in 2014, as high as 47% of the population in the European Union lacks sufficient "digital capacity", and this kind of problem is more serious in developing countries
2. Digital security is facing severe challenges
according to the data of Internet monitoring company arbor networks, the global DDoS attacks increased by more than 30 times in just three years from 2011 to 2014. A study estimates that the losses caused by various cyber crimes and attacks to the global economy are as high as $400 billion a year. The financial sector and energy instry have become the hardest hit areas
among them, the Internet of things integrates software and hardware, and can't deal with the risk challenges through simple upgrade, modification, replacement and other ways. Many developers of smart devices are small start-ups, without the resources or experience to provide complex security functions, they may encounter disaster at any time.
in addition to promoting the transformation and upgrading of the real economy, the development of digital economy also plays an important role in improving people's livelihood and enhancing social welfare. According to the survey of 34 OECD member countries concted by the world economic forum, every 10 points increase in the level of digitalization can promote the OECD happiness index to rise by about 1.3 points. For example, through a series of innovations, the government can provide a large number of integrated and innovative services for the public< The official account of WeChat, br / >, has basically formed the application system of WeChat public number, which is composed of ministries and commissions and local departments at all levels. It has achieved full coverage of government functions such as public security, tourism, food and drug administration, party and government, transportation, ecation, medical treatment, human rights protection, justice, foreign trade and so on. In many areas of government affairs and people's livelihood, wechat service has become the norm
the digital economy also actively expands the field of life and forms a new format of convenient services. Water and electricity payment allows users to enjoy fingertip life payment at home; Cooperation in catering, housekeeping, logistics, ecation, medical care, tourism, hotel, parking, community and other fields will form intelligent solutions and develop a new o2o service mode
don't understand digital economy? You will become a "new illiterate" in the new era.
while enjoying the benefits of digital economy, workers are also suffering from the al skills challenge brought by it digital skills and professional skills. However, there is a widespread shortage of digital technology talents in various countries, and 40% of companies say it is difficult to find the data analysis talents they need. Therefore, high digital literacy has become an important factor for workers to win in the job market
for consumers, if they do not have basic digital literacy, they will not be able to correctly use information and digital procts and services, and eventually become "illiterate" in the digital era. Therefore, digital literacy is regarded by the United Nations as a basic human right in the digital era and a basic ability as important as listening, speaking, reading and writing. Improving digital literacy is not only concive to digital consumption, but also concive to digital proction. It is one of the key elements and important foundations for the development of digital economy
four problems of digital economy
although digital economy is the general trend, it also faces some obstacles to be overcome in the process of development
1. The problem of digital divide is still serious
at present, there are still 4 billion people in the world who can not access the Internet, and there is a lack of digital skills in all countries. According to the statistics of the European Union in 2014, as high as 47% of the population in the European Union lacks sufficient "digital capacity", and this kind of problem is more serious in developing countries
2. Digital security is facing severe challenges
according to the data of Internet monitoring company arbor networks, the global DDoS attacks increased by more than 30 times in just three years from 2011 to 2014. A study estimates that the losses caused by various cyber crimes and attacks to the global economy are as high as $400 billion a year. The financial sector and energy instry have become the hardest hit areas
among them, the Internet of things integrates software and hardware, and can't deal with the risk challenges through simple upgrade, modification, replacement and other ways. Many developers of smart devices are small start-ups, without the resources or experience to provide complex security functions, they may encounter disaster at any time.
7.
April 1 marks the first anniversary of the establishment of China (Shaanxi) pilot free trade zone. Over the past year, the pilot free trade zone has made Shaanxi deeply integrated with the world
in order to further boost the development of China (Shaanxi) pilot free trade zone and build a more convenient "RMB online Silk Road" for provincial enterprises to go out, the launching ceremony of Shaanxi cross-border e-commerce RMB settlement service platform of "Tongsi road" was held on April 16 and officially settled in Chanba ecological zone. The platform provides customs clearance and other services for Shaanxi export enterprises, and allows farmers to sell "mountain goods" to the international market without leaving home
Yang Liuqi, Secretary of the Party Working Committee of Chanba Ecological District in Xi'an, told reporters that the development of the "Silk Road" platform will be divided into three stages. The period from 2018 to 2019 is a period of steady improvement, with continuous optimization of website user experience and timely access to the system ports of customs and inspection and quarantine departments; 2020-2023 is a leap forward development stage, focusing on improving platform functions, expanding online proct categories, and enhancing proct transaction scale; 2024-2028 is the stage of pursuing excellence. Relying on the frontier technologies such as blockchain, big data and traceability system, we will become the whole instry chain foreign trade electronic trading service provider integrating information flow and the deep investment and financing financial service provider
8. Brief introction to UnionPay card:
I. according to the type, it can be divided into debit card and credit card
debit card
debit card refers to the card that the cardholder deposits in the issuing bank first and then makes transactions. The debit card is easy to carry. It can not only deposit and withdraw money at the bank counter, but also operate at ATM, which is very convenient. It can also earn interest by saving with the debit card
credit card
credit card is a kind of bank card that the issuing bank gives the cardholder a certain amount of credit, within which the cardholder can consume first and repay later. The difference between debit card and credit card is that CVV code with three Arabic numerals is printed on the signature strip on the back of credit card<
2. UnionPay card use
1. UnionPay card exclusive discount, card friends enjoy the rights and interests
UnionPay cardholders can not only enjoy the preferential treatment of each issuing bank, but also enjoy UnionPay exclusive discount. All kinds of online and offline exclusive card swiping courtesy, from the UnionPay card friend's day in June to the multi-purpose card discount and holiday marketing throughout the year, have been wonderful throughout the year; There are more preferential merchants all over the world, so that you can enjoy extra surprises while swiping your card! You can check the exclusive discount of UnionPay card around you through our UnionPay discount map to be a smart consumer< At present, the acceptance network of UnionPay cards has been extended to more than 140 countries and regions, where Chinese people often go, UnionPay cards can be used, and wage cards and savings cards can be used directly abroad< 3. Free of currency conversion fee, convenient and affordable.
UnionPay card is free of currency conversion fee when it is used overseas. UnionPay specifically exempts the currency conversion fee which accounts for 1-2% of the total amount of card swiping for cardholders, and saves 1-200 yuan by swiping 10000 yuan. Overseas remember to choose UnionPay card or UnionPay network.
I. according to the type, it can be divided into debit card and credit card
debit card
debit card refers to the card that the cardholder deposits in the issuing bank first and then makes transactions. The debit card is easy to carry. It can not only deposit and withdraw money at the bank counter, but also operate at ATM, which is very convenient. It can also earn interest by saving with the debit card
credit card
credit card is a kind of bank card that the issuing bank gives the cardholder a certain amount of credit, within which the cardholder can consume first and repay later. The difference between debit card and credit card is that CVV code with three Arabic numerals is printed on the signature strip on the back of credit card<
2. UnionPay card use
1. UnionPay card exclusive discount, card friends enjoy the rights and interests
UnionPay cardholders can not only enjoy the preferential treatment of each issuing bank, but also enjoy UnionPay exclusive discount. All kinds of online and offline exclusive card swiping courtesy, from the UnionPay card friend's day in June to the multi-purpose card discount and holiday marketing throughout the year, have been wonderful throughout the year; There are more preferential merchants all over the world, so that you can enjoy extra surprises while swiping your card! You can check the exclusive discount of UnionPay card around you through our UnionPay discount map to be a smart consumer< At present, the acceptance network of UnionPay cards has been extended to more than 140 countries and regions, where Chinese people often go, UnionPay cards can be used, and wage cards and savings cards can be used directly abroad< 3. Free of currency conversion fee, convenient and affordable.
UnionPay card is free of currency conversion fee when it is used overseas. UnionPay specifically exempts the currency conversion fee which accounts for 1-2% of the total amount of card swiping for cardholders, and saves 1-200 yuan by swiping 10000 yuan. Overseas remember to choose UnionPay card or UnionPay network.
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