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Satoshi Nakamoto compared the generation of Bitcoin by consuming CPU power and time to a gold mine consuming resources to inject gold into the economy. Bitcoin mining and node software mainly initiate zero-knowledge proofs and verify transactions through peer-to-peer networks, digital signatures, and interactive proof systems. کانال سیگنال آرکاکوین

Each network node broadcasts transactions to the network. After these broadcast transactions are verified by miners (computers on the network), miners can use their own work proof results to express confirmation, and the confirmed transactions will be packaged in In the data block, the data blocks will be strung together to form a continuous chain of data blocks. Satoshi Nakamoto himself designed the first version of the Bitcoin mining program,[1] this program was later developed into the widely used first-generation mining software Bitcoin, which was popular from 2009 to mid-2010 .

Each Bitcoin node will collect all unconfirmed transactions and group them into a data block. The miner node will add a random adjustment number and calculate the SHA-256 hash value of the previous data block. The mining node keeps trying repeatedly until it finds a random adjustment that produces a hash value below a certain target.

Since the hash operation is irreversible, it is very difficult to find a random adjustment number that meets the requirements, and requires a process of continuous trial and error that can predict the total number of times. At this point, the proof-of-work mechanism plays its role. When a node finds a solution that meets the requirements, it can broadcast its results to the entire network. Other nodes can receive this newly solved data block and check whether it complies with the rules. If other nodes find that the requirements are indeed met by calculating the hash value (the computing goal required by Bitcoin), then the data block is valid, and other nodes will accept the data block.

block reward
In addition to packaging the received transaction information into blocks, each block will allow a certain amount of new bitcoins to be "issued" to incentivize miners who successfully discover new blocks.

کانال سیگنال ار دیجیتال
For an array of mining machines, the profit of mining with commercial personal computers is no longer greater than the cost, and it is necessary to use a large number of special-purpose chips in parallel to make a profit.
The Bitcoin system determines the number of Bitcoins issued according to the predetermined pace of currency issuance. If there is a handling fee for other payment transactions, then the miner will also get the handling fee. Since miners can decide whether to package a certain transaction information into a block, miners will give priority to transactions with higher fees for packaging. This bidding transaction method maintains the income of blockchain miners and also checks and balances the power between miners and users.

The block generation rate is expected to be one every 10 minutes, but in each data block, the newly issued bitcoins cannot exceed 6.25, and this number will be halved every 210,000 blocks, about every 4 years. It will happen once. On May 13, 2020, Bitcoin will be halved for the third time. After the halving, the current block reward is 6.25. Therefore, the total number of bitcoins will not exceed 21 million. As the number of newly issued bitcoins declines, fees will become the main motivation for mining.

Those who put computer resources into bitcoin mining activities in the earlier period have a much easier time earning bitcoins than miners who joined later. The reason for this design is mainly to ensure that enough computing power can be attracted to process data blocks in the early development stage of Bitcoin. In fact, if no one is mining, the initial transaction activity of Bitcoin cannot be processed, and the Bitcoin economy will stop functioning. [2]

First halving in December 2012
The actual time of the second halving is July 9, 2016 16:46:13 UTC[3][4], and the newly issued bitcoins in each block are currently 12.5
The third halving on May 13, 2020, the newly issued bitcoins in each block are currently 6.25
mining difficulty
In order to maintain the rate of data block generation at approximately one every ten minutes, the difficulty of generating new data blocks is adjusted periodically.

If the speed of data block generation is accelerated, then the difficulty of mining will be increased; if the speed of data block generation is slowed down, then the difficulty will be reduced. After every 2016 data blocks are produced (about two weeks), the Bitcoin system will automatically recalculate the mining difficulty of the next 2016 data blocks at the speed of data block generation in the most recent period.

The difficulty basically determines that the SHA-256 hash value of a valid data block header (English: Block Header) should be less than a certain value, that is to say, the hash value must be exactly within the target range to be considered valid. When the target interval is smaller, it means that the hit probability is lower. In other words, the higher the difficulty of mining.

Due to the explosive addition of ASIC computing equipment, the current difficulty of mining has shown a geometric progression, and the current average annual difficulty increase is about 3% [5], making the mining work of ordinary individual miners extremely difficult.

mining equipment
In the earliest days, Bitcoin miners used Intel or AMD CPU products to mine. However, since mining is a computing-intensive application, and the difficulty gradually increases with the continuous improvement of the number of miners and equipment performance, it is no longer profitable or even a loss to use CPU mining.

As of 2012, after the first quarter of 2013, miners gradually began to adopt mining equipment such as GPU or FPGA [6]. At the same time, ASIC devices were also launched in large quantities in mid-2013 [6].

Since July 2013, the computing power of the entire network has risen in a straight line due to the large number of ASIC devices put into operation. Based on the average computing power in July 2013, all CPU mining devices have been unable to generate positive returns, and FPGA devices are also close to zero. income. According to the average computing power estimate in September 2013, the existing small ASIC mining equipment developed for individuals will have almost no positive income in the next 1-2 months. A large amount of computing power is monopolized by clustered ASIC mining equipment above 5 THash/s. Personal mining is almost squeezed out of the mining group because it has no income. Some bitcoin miners raise funds to build computer rooms and install a large number of mining equipment in places where low-cost electricity is available.

In order to save their own mining costs, some Bitcoin miners make mining programs into malicious programs and infect other people's computers on the Internet to mine for themselves. سبدگردانی ارز دیچیتال

mining pool
As the computing level of the entire Bitcoin network continues to rise exponentially, no single device or a small amount of computing power can obtain the block rewards provided by the Bitcoin network on the Bitcoin network. After the computing power of the entire network has increased to a certain level, the probability of obtaining rewards is too low. It prompted some geeks on "bitcointalk" to develop a method that can combine a small amount of computing power for joint operation. The website built in this way is called "Mining Pool".

In this mechanism, no matter how much computing power an individual miner can use, as long as he participates in mining activities by joining the mining pool, no matter whether he successfully mines a valid data block, he can obtain a small amount of bits by contributing to the mining pool Bitcoin rewards, that is, multi-person cooperative mining, and the bitcoin rewards obtained are also shared by multiple people according to their contribution.

As of May 2020, the top five Bitcoin mining pools in the global computing power are: F2Pool, Poolin, BTC.com, AntPool, 58COIN&1THash, and currently about 70% of the global computing power is in the hands of Chinese miners[8].

handling fee
Bitcoin miners charge a small fee for most transactions, the main purpose of which is to prevent someone from wasting network resources by sending a large number of boring small transactions. Most of the current handling fee for each transaction is ฿ 0.0001/KB (ie 0.0001btc/KB). In fact, after version 0.9.0, the default fee will be reduced to ฿ 0.00001/KB (ie 0.00001 btc/KB). [9] Because the amount of data occupied by most transactions is less than 1 kilobyte, a handling fee of ฿ 0.00001 (that is, 0.00001 btc/KB) is generally sufficient. At the same time, when the bitcoin block rewards are less in the future, the service fee will become the main source of miners' income, and the bitcoin service fee will be related to the number of bytes occupied by the transaction.

At present, the calculation standard of handling fees in the Bitcoin system is not mandatory, so users can also not give any handling fees when transactions are in progress, but most miners usually give priority to those with higher handling fees when building data blocks. Transactions, in order to obtain higher rewards when mining is successful, so transactions without any handling fees may need to wait for a long time before they can be processed and included in the blockchain.

In addition, due to the upper limit of the block size "1MB" and the recent increase in Bitcoin transaction volume, the handling fee has risen sharply, and the waiting time for the transaction to be confirmed has also become much longer.