256 bitcoin encryption algorithm

1. In fact, the mining calculation of bitcoin is to do math problems together. The problem stem is the transaction that needs to be recorded. By doing the problem, everyone grabs the bookkeeping right, and the miners can get system rewards and transaction fees
the feature of sha256 algorithm used in bitcoin is that it's easy to verify the known answers correctly, but it's very troublesome to get the answers, and you need to try them one by one. The miner who got the answer first was recognized by everyone as having snatched the right to keep accounts, and the reward was given to him. Let's continue to grab the bookkeeping right of the next question
simply speaking, the significance of these calculations only lies in ensuring the stability and security of the whole system, and has no more significance. It is not comprehensive to regard bitcoin as a by-proct of computing. The generation and issuance of bitcoin, all the transactions and circulation in the bitcoin chain, and the stability of the bitcoin system are all the purposes of computing. Of course, in addition to maintaining the system, it does not proce other value and procts. This is also a black spot where bitcoin is accused of not being environmentally friendly and wasting resources
in general, bitcoin, as a milestone blockchain digital currency, comes from the huge value of a large amount of computing power investment and user trust. There is no doubt about that.

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. Bitcoin is a consensus network, contributing to a new payment system and a fully digital currency. It is the first decentralized peer-to-peer payment network, which is controlled by its users without a central management organization or middleman. From the user's point of view, bitcoin is much like Internet cash. Bitcoin can also be regarded as the most outstanding three style bookkeeping system

anyone can run software on specialized hardware and become a bitcoin miner. Mining software monitors transaction broadcast through P2P network and performs appropriate tasks to process and confirm these transactions. Bitcoin miners can earn transaction fees paid by users to speed up transaction processing and additional bitcoin issued according to fixed formula
new transactions need to be included in a block with mathematical workload proof before they can be confirmed. This kind of proof is hard to generate because it can only be generated by trying billions of calculations per second. Miners need to run these calculations before their blocks are accepted and rewarded. As more people start mining, the difficulty of finding effective blocks will be automatically increased by the network to ensure that the average time to find a block remains at 10 minutes. Therefore, the competition for mining is very fierce, and no indivial miner can control the content contained in the block chain
workload proof is also designed to rely on previous blocks, which forces the time sequence of block chain. This design makes it extremely difficult to cancel previous transactions, because the workload proof of all subsequent blocks needs to be recalculated. When two blocks are found at the same time, the miner will process the first block received, and once the next block is found, it will be transferred to the longest block chain. This ensures that the mining process maintains a global consistency based on processing capacity
bitcoin miners can neither increase their rewards by cheating, nor deal with the fraulent transactions that destroy the bitcoin network, because all bitcoin nodes will reject the blocks containing invalid data that violate the bitcoin protocol rules. Therefore, even if not all bitcoin miners can be trusted, the bitcoin network is still secure

sha256 is an encryption algorithm.

4. < blockquote >

when building bitcoin, Nakamoto wants bitcoin to be a decentralized currency, not only for use and trading, but also for mining. But it backfired. With the increasing value of cryptocurrency such as bitcoin, mining has become an instry. The competition is more and more fierce, and the pursuit of mining computing power is higher and higher. Therefore, from ordinary computer mining, ASIC mining machine and GPU mining machine have evolved

the algorithm of ASIC mining machine is almost sha256, while the algorithm of GPU mining is different. For example, the algorithm of BTG is equihash, and the algorithm of BCD is optimized x13. Although it is not absolute, it can be simply considered that the currency of sha256 algorithm is generally mined by ASIC mining machine. Other algorithms are basically using GPU miner. There are also exceptions. Scrypt's Leyte coin used to be mined by GPU miner, but later scrypt's algorithm was also conquered by ASIC chips, such as ant miner L3 +, which is the ASIC miner used to dig Leyte coin

ASIC miner refers to the miner that uses ASIC chip as the core of computing power. ASIC is the abbreviation of application specific integrated circuit, which is a kind of electronic circuit (chip) specially designed for a specific purpose. Some mining machinery factories have designed ASIC chips specially for computing the sha256 algorithm of bitcoin, and the mining machinery using them is ASIC mining machinery. Because ASIC chip is only built for specific computing, its efficiency can be much higher than that of CPU. For example, the current mainstream ant miner S9 is ASIC miner, which uses 189 ASIC chips, the computing power reaches 13.5th/s, and the power consumption is only 1350W. As a comparison, the computing power of gtx1080ti, the flagship computer graphics card, will not exceed 60mh / s even if it is optimized well. The difference is tens of thousands of times

GPU miner refers to the miner that uses GPU graphics card as the core of computing power. Cryptocurrencies such as Ethereum, bitcoin and diamond use graphics algorithms, so the speed of computing with graphics card will be the highest. Compared with ASIC miner, GPU miner is more well-known, because it is a computer with enhanced graphics card configuration

the purpose of GPU miner is to make money, so we should pursue the power consumption ratio and maximum profit, so we should pay attention to the cost performance. Generally, the medium and high-end positioning graphics cards, such as AMD rx560 and rx570, have high power consumption ratio, which is a good choice for GPU miner. While flagship cards such as gtx1080ti and AMD vega64 have the strongest single card performance, they are not cost-effective in terms of price and power consumption

in addition, the ASIC miner also has some exotic procts, such as the USB miner of burning cat, which is slightly larger than the U disk, and the power consumption is only 2.25w, which is the smallest bitcoin miner at present

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the above quoted digcoin.com - "Introction to mining machinery classification" has many professional terms. I hope it can help you, thank you

5. There is no way to count this, because there are so many digital currencies in this algorithm. One of the most famous is bitcoin, which has more than half of the 21 million bitcoins. There is no way to make specific statistics of Shanzhai coins of other similar algorithms. Moreover, the number can be changed, just change a number in the code

in addition to bitcoin, there are also well-known digital currencies such as Leyte coin and Ruitai coin.

6.

there are about three kinds of currency in currency speculation. one is the base currency, which is similar to the representative of money. CNY and usdt Basic goods with value). One is the mainstream token, BTC, ETH (because of the national restrictions, the exchange can only trade in token, that is, take one kind of virtual currency to buy another kind of virtual currency, I don't know why.) The other is a variety of virtual currencies (commodities)

the purchase process is to first go to the exchange platform to find a personal seller with RMB to exchange for usdt, In the process of using usdt to exchange for the mainstream token BTC or eth used in purchasing various virtual coins, and finally using eth to purchase various virtual coins

A. base currency: CNY, usdt (exchangeable, need to be exchanged in good faith transactions with indivial buyers) B. mainstream token: BTC, ethc, virtual currency: all kinds of money, such as profit, need to be exchanged into usdt again, and then sold into CNY. Learn more about the coin circle

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sharing area network ~ learn more about the coin circle

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experience: 1. Buy mainstream currency if you can't buy it. 2. If the new currency is not fried in January, it may become a banker to harvest leeks. 3. Just learned an experience, chasing up and killing down, meaning up do not buy, buy must be cut leeks If you have strength and value, you can hold it and wait for salted fish to turn over. 5. If the company is strong, the team is strong, and the executives are strong, you can pay more attention to it. Note: I don't understand the K line at all, and I don't understand the professional words, so I can only make a tentative decision on these purchase principles based on logical thinking

7. There are mainly two kinds of bitcoin algorithms, which are elliptic curve digital signature algorithm and sha256 hash algorithm

elliptic curve digital signature algorithm is mainly used in the generation process of bitcoin public key and private key, which is the cornerstone of bitcoin system. SHA-256 hash algorithm is mainly used in the workload proof mechanism of bitcoin

the principle of bitcoin generation is the special solution generated by complex operation, and mining is the process of finding the special solution. However, the total number of bitcoin is only 21 million, and with the continuous mining of bitcoin, the more difficult it will be to proce bitcoin, and the cost of acquiring bitcoin may be higher than the price of bitcoin itself

the bitcoin block consists of a block header and the transaction list contained in the block. The size of the block header is 80 bytes, which is composed of 4-byte version number, 32 byte hash value of the previous block, 32 byte Merkle root hash, 4-byte timestamp (current time), 4-byte current difficulty value and 4-byte random number. A block header with a fixed length of 80 bytes is the input string used to prove the workload of bitcoin. Constantly change the random number in the block header, that is, the value of nonce, and do double sha256 operation on the block header after each change, and compare the result value with the target value of the current network. If it is less than the target value, the problem is solved successfully, and the workload is proved to be complete

the essence of bitcoin is actually the unique solution of a set of equations generated by a bunch of complex algorithms. Bitcoin is the first distributed virtual currency in the world, which has no specific distribution center. The network of bitcoin is composed of all users, because there is no center to ensure the security of data.

8. This is a mathematical trap. RSA is a typical example, while sha256 is more advanced. For example, according to the algorithm, the password 123456 can be calculated as a 64 bit or 128 bit key. With such a long key, 123456 can't be inverted. Unless you knew it was 123456. Mining is actually not decoding, but calculating the code. From 00000 1, a 64 bit key is calculated, and then compared with 123456, until 123456 times is calculated from 00000 1, and the key of 123456 is calculated. This time, the block belongs to you. The public key of each block is different, so the 123456 of the previous block calculates a series of numbers, and the 123456 of the later block is the same as the starting point, so the number calculated is different from that of the previous block

9. Bitcoin system uses asymmetric encryption to improve transaction security. This is what people from Yingfu College of Finance and economics told me. There was a friend there at that time

in the process of information encryption and decryption, different keys are used. Only the corresponding public key can be used for decryption. Owning the private key is equal to owning the ownership of bitcoin

similarly, bitcoin users also need to pass authentication to ensure the ownership of their own cryptocurrency assets.