Electronic map of bitcoin

1. bitcoin is a kind of virtual currency, which is characterized by decentralization, anonymity, and can only be used in the digital world. It does not belong to any country or financial institution, and is not subject to geographical restrictions. It can be exchanged in the world
reference link: http://wuhan.pbc.gov.cn/wuhan/2929354/3393665/index.html

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

3. Ah, the transaction logic of bitcoin is generally based on a principle of a blockchain, and then as we say, it is a buy and buy out of content

4.

Novice first of all to know how to calculate your cost, recharge, trading, cash, there are fees. At least you can understand the K-line. There are a lot of people on the K-line. You can look at it casually and understand it. You need to be risk aware. Bitcoin is a high-risk and high profit investment. It may double overnight, or BMW may become a bicycle overnight. At the beginning, we suggest a small amount of investment

but it's hard to get bitcoin for indivial mining, so it's basically large-scale mining, and you need to cooperate with the mine pool. So if you still want to make money by mining, at present, the most suitable mining method is cloud mining or mining machine hosting. After all, the era of single person mining is over

6. Abstract: a person named Satoshi Nakamoto posted a post on the P2P foundation website, saying that he has developed an open-source P2P (peer-to-peer) e-cash system called bitcoin, which is completely decentralized. There is no central server or trustee, and everything is based on participants.

7.

The concept of bitcoin was first proposed by Nakamoto in 2009. According to Nakamoto's idea, open source software was designed and released, and P2P network was built on it. Bitcoin is a kind of P2P digital currency. Point to point transmission means a decentralized payment system

Bitcoin economy uses the distributed database composed of many nodes in the whole P2P network to confirm and record all transactions, and uses the design of cryptography to ensure the security of all aspects of money circulation

bitcoin: also known as "bitcoin", is a kind of network virtual currency. Internet users can use bitcoin to buy some virtual goods, such as clothes, hats, equipment, etc. in online games. Internet users can also use bitcoin to buy real goods

bitcoin network generates new bitcoin through "mining". In essence, the so-called "mining" is to use computers to solve a complex mathematical problem to ensure the consistency of bitcoin network distributed accounting system. Bitcoin network will automatically adjust the difficulty of mathematical problems, so that the whole network will get a qualified answer about every 10 minutes. Then bitcoin network will generate a certain amount of bitcoin as a reward to reward the person who gets the answer

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users can buy bitcoin, and at the same time, they can use computers to "mine" bitcoin according to a large number of calculations. When users "mine" bitcoin, they need to search for 64 bit numbers by computer, and then compete with other gold diggers by repeatedly solving riddles to provide the required numbers for bitcoin network. If the user's computer successfully creates a set of numbers

bitcoin is e-cash similar to e-mail. Both parties need "bitcoin wallet" similar to e-mail and "bitcoin address" similar to e-mail address. Just like sending and receiving e-mail, the remitter pays bitcoin directly to the other party through a computer or smart phone according to the recipient's address. The following table lists some websites that download bitcoin wallets and addresses for free

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network bitcoin

8. For bitcoin, don't invest any more. It's a complete gamble. Remember, don't participate, especially at this stage. The threshold itself is very low. Bitcoin is not money. It can be divided into any large unit, such as 0.0000015 bitcoin. I don't know when the concept of bitcoin was changed into bitcoin. It can be worthless at any time

9.

Last week, a paragraph about bitcoin became popular:

bitcoin broke through 5800 US dollars (about 38280 yuan) . When it was issued in 2009, 1 US dollar was equivalent to 1300 bitcoins. What is investment? It has increased by 7.54 million times in 8 years. At that time, you spent 38000 yuan to buy some bitcoin. Now you are the richest man in China, surpassing Xu Jiayin, who has 290 billion yuan

but just one week later, on October 20, bitcoin broke through the $6000 mark. Although it fell later, it reached more than $6000 again on October 21, reaching a maximum of $6147. In terms of $6000, bitcoin prices have risen 7.8 million times in eight years

according to cryptocompare, a bitcoin data provider, e to China's strict supervision of cryptocurrency trading, the global share of bitcoin market has been greatly changed. Now, in the total trading volume of the world's bitcoin exchanges, the trading volume of RMB versus bitcoin accounts for about 1.6%

} the proportion of RMB and yen in global bitcoin trading volume (photo source: cryptocompare)

the reporter noted that in the first half of this year, after Japan's legislation recognized bitcoin as a legal payment method, bitcoin's trading volume in Japan surged, and Japanese regulatory authorities have issued certificates to 11 cryptocurrency exchanges. About 58% of bitcoin trading currently takes place in the Japanese market, and nearly a third of yen to bitcoin trading takes place on the bitflyer exchange in Tokyo. In addition, the U.S. and South Korea markets also account for a large part of global bitcoin transactions - the U.S. dollar and the Korean won account for 27% and 7% of the total bitcoin transactions, respectively< br />