1. Security in
blockchain comes from some attributes<
mining blocks need to use resources< Br > 2. Each block contains the hash value of the previous block< Br > imagine if the attacker wants to change the chain by changing the transaction five blocks ago. If they tamper with the block, the hash value of the block changes. Then the attacker must change the pointer from the next block to the changed block, and then change the hash value of the next block... This will continue until the end of the chain. This means that the farther the block is behind the chain, the greater the resistance to change. In fact, the attacker has to simulate the hash capability of the whole network up to the front end of the chain. However, when the attacker tries to attack, the chain continues to move forward. If the attacker's hash value is lower than the rest of the chain (< 50%), they will always chase and never proce the longest chain. Therefore, this type of blockchain can resist attacks, where the attacker's hash value is less than 50%< Br > when attackers have 51% hash value, they can rewrite the network history with a list of valid transactions. This is because they can recalculate the hash value of any block sort faster than the rest of the network, so they can ultimately guarantee a longer chain. The main danger of 51% attacks is the possibility of double spending. This simply means that an attacker can buy an item and show that they have paid with any number of confirmations on the blockchain. Once they receive the item, they can reorder the blockchain so that it doesn't include the send transaction and get a refund< Br > even if the attacker has more than 50% hash value, the attacker can only do so much damage. They can't do things like transfer money from the victim's account to their account or print more coins. This is because all transactions are recorded by the account?? Account owners sign, so even if they control the entire network, they cannot forge account signatures.
2. Nodes are the places where the blocks are connected, and the blocks need to be chained to be useful
core analysis:
1. Transparency, 2. Openness, 3. Information can not be tampered with, 4. Decentralization,
5. Detailed analysis
blockchain is a new application mode of distributed data storage, point-to-point transmission, consensus mechanism, encryption algorithm and other computer technologies. The so-called consensus mechanism is a mathematical algorithm to establish trust and obtain interests between different nodes in the blockchain system
1. In a narrow sense, blockchain is a kind of chained data structure composed of data blocks connected in sequence according to the time sequence, and it can not be tampered with and forged by cryptography
2. Broadly speaking, blockchain technology uses blockchain data structure to verify and store data, uses distributed node consensus algorithm to generate and update data, and uses cryptography to ensure the security of data transmission and access It is a new distributed infrastructure and computing method to program and operate data by using intelligent contract composed of automated script code.
3. Blockchain is a technology to achieve decentralization, and it is an application model of a variety of Internet basic technologies. In essence, blockchain is actually an application model similar to internet protocol. The HTTP we usually log in to is an internet protocol. The Internet connects the global network through the underlying protocol, while the application protocol of blockchain is a new way to connect the network nodes distributed around the world. In the future, more and more people will understand and accept blockchain.
4. If you lose the mnemonic words in the
digital currency wallet, it is almost equal to the loss of the private key. Mnemonic words are just a form of the private key that is easier to understand. If you lose the private key, it is almost equal to the loss of the digital currency in the wallet. With the current technology, it is impossible to crack it. Therefore, if you forget it, you can only recognize it. Change the wallet and back up the mnemonic words
5. In the traditional supply chain finance, financing difficulty, high financing cost and cumbersome financing process have always been one of the bottlenecks restricting small and medium-sized enterprises to become bigger and stronger. Banks rely on the ability of core enterprises to control goods and regulate sales. For the sake of risk control, banks are only willing to provide factoring services to upstream suppliers (limited to first tier suppliers) with direct accounts payable obligations of core enterprises, or provide prepayment or inventory financing to their downstream distributors (first tier suppliers). As a result, the demand of secondary and tertiary suppliers / distributors with huge financing demand can not be met, the business volume of supply chain finance is limited, and the small and medium-sized enterprises can not get timely financing, which will easily lead to proct quality problems and damage the whole supply chain system
to solve these problems, we can make use of the characteristics of decentralized, tamper proof and distributed ledger of blockchain technology to build a blockchain supply chain financial platform
The core enterprise issues a / R certificate to the distributor. After the distributor signs the receipt, it indicates that it has signed the purchase and sales contract and the core enterprise delivers the goods Because of the shortage of funds, distributors need to borrow money from finance
3. After the financial institutions have approved, the amount of loans will be sent to the core enterprises
The distributor will repay the loan and interest after selling the goods
6. I choose Chinese currency! Low operation delay, idle can also save money mining EOS, very suitable.
7. Xiong'an blockchain can't log in. You can refresh it or reload the system.
8. Don't users log in with mobile phone verification code? Just change your mobile phone number
