BTC wallet node
According to 1ml data, the current number of bitcoin lightning network nodes has reached 18061, an increase of 7.30% in the past 30 days; The number of channels was 40065, which increased by 5.9% in the past 30 days; Network capacity reached 1154 BTCs, an increase of 6% in the past 30 days
blockchain technology workstation under "BTC
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1) wallet. It's used to store your bitcoin balance. In principle, as long as you have the private key of your own bitcoin address, you can use your own bitcoin
2) verify the transaction or payment. After receiving the transaction, the bitcoin node will use certain algorithms to verify the validity of a transaction. If you only change the balance of bitcoin in your computer, others will not recognize it. Similarly, your wallet will not recognize the transaction changed by others
3) mining. Core wallet can start mining function through a command to join the mining army, while SPV wallet usually can't (SPV is just passing by). However, it is not the node type that hinders home computer mining, but the rapid development of professional mining machines. Compared with ordinary computers, the computing power of ordinary computers is very small. Mining by ordinary computers is like digging your own backyard with a hoe, and then expecting to dig out gold
because of the demand of bitcoin users, bitcoin exchange was born. The exchange provides a place for centralized trading. People put money on the exchange, and the exchange will match and trade together, similar to stocks and securities. Therefore, banning exchanges does not mean banning bitcoin. Bitcoin network cannot be banned. Bitcoin is sent to the exchange's wallet, and all you see is a balance given to you by the exchange. In fact, you no longer have your own bitcoin. Bitcoin network is global. Where there is a network, there will be bitcoin. After the exchange closes, bitcoin will not disappear, but will return to where it should be.
in terms of cloth storage and mining, I recommend Heshu hardware wallet and jiajiabao intelligent home miner. The core advantage of the proct is safety
take sum hardware wallet as an example. The advantages of sum hardware wallet are as follows:
1. The private key seed is encrypted layer by layer, physically isolated and never touched the Internet.
firstly, when creating the wallet, the seed password is generated and stored in the local encryption chip, and the 10 bit payment password is required
then, the transaction is made in the wallet. At this time, the user needs to enter the payment password to obtain the private key to digitally sign the transaction, and the transaction is completed. In addition, the private key seed is permanently stored in the chip, which is physically isolated and never touches the Internet. There is no need to worry about my password being stolen by hackers
Second, the bank system verifies the financial level motherboard and encryption chipuses the bank system to verify the financial level motherboard, and the private key seed is stored in the chip. If the proct is stolen or lost, and destroyed by malicious violence, the chip will trigger a self destruct circuit, and immediately permanently and irrecoverably delete all the information in the area
Third, it supports the withdrawal of global bitcoin ATM, which is convenient and fastthe reason why digital assets attract the attention of many fields in the world is that it is creating a global fast circulation, and the larger the circulation field is, the wider the scope is, and the higher its use value is. The core of digital assets is the medium it acts on among currencies. The Heshu wallet has built-in many mainstream exchanges in the world. It can trade digital assets anytime and anywhere. With one machine in hand, it can walk around the world without worry, and no longer have to worry about exchanging foreign currency
Different from conventional digital wallets, multi signature wallets need the authorization of multiple key holders to transfer digital currency, so the security of multi signature wallets is higher. Ordinary Wallet: a wants to transfer a bitcoin to X. A only needs his signature (using the private key) to complete the transaction. Sum Wallet: if a wants to transfer a bitcoin to x, a multi signature verification is set (at least two signatures of Abc3 indivials are required to transfer the money), then a needs B or C to complete the signature (using the private key) when a wants to transfer the money to X. I hope I can help you. Thank youa 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.
bitcoin is a kind of point-to-point e-cash system, more directly, node to node. Each transaction is broadcast by the originator to the nodes around it, and then broadcast to the nodes around it after receiving it, and finally spread to the whole network
every bitcoin wallet is a node, and the node with a complete blockchain ledger is called the whole node. In October 2017, there were about 9300 nodes in the bitcoin network, which were responsible for broadcasting and verifying bitcoin transfer transactions. After the transfer transaction occurs, all nodes broadcast to the whole network. After the mining node verifies that the transaction is correct, it will be recorded in the blockchain ledger. The United States, Germany and France have the largest number of bitcoin nodes, with China accounting for about 5% of the world's total nodes Data source: bitcodes. 21. CO) running bitcoin node does not provide any reward, and it does not need the whole node to transfer bitcoin, so the total number of bitcoin nodes only accounts for a small part of the node number.