How big is bitcoin's block packet

1. It depends on the project. Take bitcoin as an example. Now the account book that records all the information of bitcoin network may reach 220g.

2. Bitcoin was born in a paper in 2008
a person signed by Nakamoto Tsui has put forward a revolutionary idea: let's create a currency that is not controlled by the government or anyone else! This idea is crazy: there is no asset support behind a string of figures, and no one is responsible for it. How can anyone accept it when you pay it to the other party as money
Merkle tree
looks like a binary tree, but this is the lower two nodes. Take the hash value to get the upper node. Just remember the root node to detect whether the whole tree has been tampered
the root hash value is stored in the block header, and the transaction process is stored in the block body. All nodes include block header and block body, but light nodes (such as bitcoin wallets on mobile phones) only include block header. This tree can prove that a transaction has been written into the blockchain
3. Consensus agreement
two issues should be paid attention to in decentralized currency:
1. Who can issue digital currency: mining
2. How to verify the legitimacy of transactions: blockchain
double spending attack
double spending attack is a major challenge of digital currency
all transactions in bitcoin have input and output. Where does bitcoin come from and where does it go
under normal circumstances, there may be two bifurcations, because two nodes obtain the bookkeeping right at the same time, and the two nodes package the block and calculate the random number at the same time. At this time, the two bifurcations will coexist temporarily until one of the blocks finds the next block first, which becomes the longest legal chain, and the other one is discarded<

Sybil attack
a malicious node keeps generating accounts. If the total number of accounts exceeds half of the total accounts, it obtains the control of the blockchain

consensus protocol in bitcoin
some nodes are malicious, and most nodes are good

idea 1: pack some transactions into blocks as candidate blocks, let each block vote, and write them into the blockchain if they pass

No, because some malicious nodes have been publishing blocks containing malicious transactions, and they have been voting and occupying resources. And some nodes don't vote<

idea 2: vote not by the number of accounts, but by computing power. Each node can generate legal transactions and put them into the block. These nodes start to try random numbers until H (block header) ≤ target is found, then this node has the right to account

the only way to generate bitcoin
coinbase transaction. There is no need to point out the source of the currency. If you have the bookkeeping right, you will get a reward< br />
50BTC-> 25BTC-> 12.5btc, the reward will be halved for every 210000 bitcoins

the process of bitcoin competing for bookkeeping rights is called mining. The node competing for bookkeeping right is called miner.

3.

What are the wallets in our lives? Put your money, cards, and mobile phone, money and bank cards are issued by the bank. Mobile phone Alipay WeChat payment is paid through the third party, which is completely decentralized, and how it will be stored and retained? Besides being placed in the exchange, it can also be placed in the wallet. What are the types of bitcoin wallets? How to achieve point-to-point decentralization? Blockchain wallet is not used to hold money?! Have you stepped on thunder

miaozhou blockchain issue 08 can teach you to identify the mistakes of blockchain wallet. More blockchain beginners are welcome to pay attention to Babbitt's miaozhou blockchain

4. A block size of bitcoin is 1MB. There is no limit on the size of each transaction. A block can generally contain 2000-3000 transactions.

5. Each block contains the information of all recent transactions, a nonce (random number) and the hash value of the previous block. When the SHA-256 hash value of the whole block is lower than the current target value, it is marked as "resolved" (published and verified by multiple nodes). Usually, it is difficult to achieve the goal by hashing once, so nonce must be increased, and blocks must be hashed millions of times to achieve the goal.

6. Each block contains the information of all recent transactions, a nonce (random number) and the hash value of the previous block. When the SHA-256 hash value of the whole block is lower than the current target value, it is marked as "resolved" (published and verified by multiple nodes). Usually, it is difficult to achieve the goal by hashing once, so nonce must be increased, and blocks must be hashed millions of times to achieve the goal. Bitcoin transactions are broadcast to the network through remitters, and all mining nodes (clients) collect bitcoin and add it to their working blocks. If the transaction volume is large, exceeding the average transaction volume, the network will dect a small amount of transaction fees. The first transaction in each block is special: it creates a new bitcoin for the first person to take a valid block. Other nodes (clients) will only accept the block when the transaction amount is correct. The number of bitcoins generated per block is 50, which is halved for every 210000 blocks (about four years). The network tries to create six blocks per hour. Every 2016 blocks (about two weeks), all bitcoin clients will compare this target with the number of blocks actually created, and modify the difficulty percentage of block acquisition to maintain this target. The client believes that the "longest" blockchain is effective. The "length" of the whole blockchain refers to the chain with the most difficulties, not the chain with the most blocks. This can prevent someone from forging and creating a large number of low difficulty blocks, which can be accepted as the "longest" chain by the spoofing network. How many blocks have been collected? Click here to see the current number of blocks collected. What is the maximum number of blocks? There is no maximum number. Will blocks continue to be added to the end of the blockchain at a rate of 10 minutes, even after all 21 million bitcoins are collected[ b] Yes. Blocks are used to prove that a transaction exists at a specific time. After all bitcoins have been collected, the transaction will still take place. So as long as someone trades bitcoin, the block will still be created[ b] How long does it take to acquire a valid block? No one can say it accurately. There is a mining calculator that will tell you how much time it might take. What does it mean if I calculate that the progress of a block has increased by 1%? There is no saying that the progress will increase by 1%. Each operation does not increase progress. After 24 hours of calculation, your chance of getting bitcoin is the same as when you first calculated it. This is the same as rotating 37 coins at the same time and making them face up. Every time you try, your chances of success are the same.

7. Triporg travel: a travel service application using blockchain, which provides booking services such as air tickets and train tickets.

8.

1. During the first phase of the interstellar war, players only need to place the hang up location in the first and second levels of each map, and they will get a crystal ore as well as props. Because the first and second levels can get props once an hour, So players can get 24 crystal ores in one day, and 24 * 7168 crystal ores in seven days

2. During the activity period, players only need to open any treasure box in the mining area to a certain extent to get the crystal ore reward, which is divided into five grades

3. Electronic competition Wallet: ring the activity period, you can get rewards when you recharge to a certain amount, among which you can get crystal ore bag when you recharge more than 30 yuan, and you can get 100 crystal ore when you open the crystal ore bag

accumulatively support 50 crystal ores to obtain: honor fragment * 1000, detonator * 5, troll statue * 5, mysterious stone * 1

9. I went to have a look. Yes, it is. It refers to the quantity that each block can obtain at present. For example, BTC's is 25, which means that at present bitcoin has a reward of 25 coins per block. Biter's expression is not accurate. You can go to Babbitt's currency circle and suggest that biter make corrections.

10. The historical data of bitcoin wallet is relatively large
generally speaking, the historical data of bitcoin wallet includes all the historical information about bitcoin transactions; But for indivials, they generally only need to download historical data related to their bitcoin
now there are more bitcoin wallets in the form of online wallets; Indivial users only need to register their account information to manage their wallets. In this way, indivial users basically do not need to consider the historical data of bitcoin wallet.