Italian referendum on bitcoin

1. 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

2. Bitcoin virus (bitcoin Trojan horse) & quot; Bitcoin blackmailer & quot; It was popular abroad in 2014, and was found in China in early 15 years. This kind of Trojan will encrypt 114 kinds of files in the infected computer, such as docx, PDF, xlsx, JPG and so on, so that it can not be opened normally, and pop up the window & quot; Blackmail & quot; Victim, ask victim to pay 3 bitcoin as & quot; Ransom;, According to the recent price comparison of bitcoin found by the reporter from the Internet, 3 bitcoin is about 5000 yuan or 6000 yuan. This kind of Trojan horse is generally spread through English mail, and the name of the Trojan horse program is usually English, which means & quot; Order & quot& quot; Proct details & quot; And use fax or form icon, which is very confusing. The recipient easily mistakenly thinks that it is a working file and clicks to run the Trojan horse program
in May 2017, computer network virus attacks have spread to 74 countries, including the United States, the United Kingdom, China, Russia, Spain, Italy, etc.

3. On May 12, 2017, wannacry, a global computer blackmail virus, broke out, affecting more than 150 countries. 75000 computers were infected, and 99 countries were attacked, including the United Kingdom, the United States, China, Russia, Spain and Italy. On May 17, 2017, the National Computer Virus Emergency Response Center and Asia Information Technology (China) Co., Ltd. jointly monitored and found that a new variety of blackmail virus named "uiwix" appeared in foreign countries, reminding domestic users to be on guard. On June 28, 2017, the blackmail virus Petya attacked many countries. Petya virus locked a large number of computers and required users to pay $300 in encrypted digital currency to unlock them
on the evening of June 29, 2017, Petya, a new blackmail virus, was found in Ukraine, Russia, Spain, France, Britain, Denmark and other countries. On July 4, 2017, Ukrainian police confiscated the server of an accounting software company in Ukraine, which was suspected of spreading the blackmail virus that paralyzed the computer systems of many large companies around the world.

4. Generally, it's legal, but I don't think it's reliable. If you put it in your wallet, it's equivalent to being in someone else's, so you can't make your own decisions

6. According to media reports, recently, affected by the external market exchange rate fluctuations, its own scarcity and other factors, bitcoin once again staged a wave of soaring prices, and buyers from all sides rekindled their enthusiasm for virtual currency speculation. According to relevant trading platform data, the price of bitcoin rose nearly 30% within a few days after the British referenm on brexit, and the trading volume increased significantly month on month. Instry insiders pointed out that bitcoin, known as "electronic gold" in the instry, has also become a safe choice for international funds after the British referenm on brexit.

7.

Around 20:00 on May 12, 2017, bitcoin blackmail computer virus broke out in the world, which is a global blackmail software infection event

5.360 security guard has provided "NSA Arsenal immunization tool", which can be downloaded and installed

8. The largest city in Slovenia, the largest city in Slovenia, seems to be the largest city in that city.

9. Salesman is the broker who looks for the buyer and the seller to trade. The top salesman image is a combination of Scout's head, crosstalk actor's eloquence, marathon athlete's enrance, general's demeanor and indomitable mountaineer's spirit
without a strong desire to realize self-worth, indomitable spirit, agility and flexible intelligence, you can't cross the threshold of a salesman
the salesman's job is to extract glittering gold from thousands of tons of ore; It is to select real buyers from thousands of customers; It is to win the favor of the customers by beating the competitors in the competition
when a salesman sells a proct, he or she actually sells himself or herself first - comprehensive qualities such as professional level, negotiation skills and moral character. If the customer does not accept the quality and image of the salesman, they will not be able to accept the proct
business elites with high quality constantly review their shortcomings in their work and constantly improve their marketing skills; And the low-level salesman will constantly complain about how the customers create difficulties for themselves, or complain that the procts are too difficult to occupy the market, so as to push themselves to a low-level position, and then be eliminated by the strong hand in the same instry
confidence is the lamp and perseverance is the generator. If the salesperson does not have the power source of strong perseverance, the lamp of confidence will not always be bright, so it is impossible to explore rich achievements
the excellent business method is to make customers willingly pay their remuneration, and still admire them. Otherwise, the customer not only will not pay, but also a look of disdain
the motivation of salesmen is not generated by the coercion of the boss, the temptation of the boss and the ridicule of colleagues, but a strong passion generated by themselves, that is, the action of "not being a hero without reaching the Great Wall". In this way, its daily plan, action, enlightenment and harvest will be carried out in an orderly way.