wholesale natural jewelry cleaner 108 knowledge points of the blockchain

wholesale jewelry bags fabric with company logo Blockchain entry must -have 108 knowledge points
(Welcome to communicate with the same frequency)
1, what is the blockchain
Together, this package after verification is the block.
The hash value of the previous block is saved in each block, which causes relationships between the blocks, that is, the chain. It is called the blockchain.

2. What is Bitcoin
The concept of Bitcoin was proposed in 2009, with a total of 21 million. Bitcoin chain produces a block for about every 10 minutes. This block was dug out for 10 minutes. As a reward for miners, a certain number of Bitcoin will be issued to the miners, but this certain number is halved every four years. It is 12.5 now. Following this, all Bitcoin came out in 2040.
3. What is Ethereum
The biggest difference between Ethereum and Bitcoin is that there are smart contracts. Make developers develop and run various applications.
4. Distributed ledger
It is a database sharing, copy and synchronization between members of the network. Straight speaking, all users on the blockchain have the bookkeeping function, and the content is consistent, which ensures that the data cannot be tampered with.
5. What is quasi -anonymous
It believes that everyone has wallets, and the wallet address (a string of string) used by sending transactions is quasi -anonymous.
6. What is open transparency/traceability
The blockchain stores all the data from history to the present, anyone can view anyone, and you can also see any data in history.
7. What cannot be tampered with
The historical data and current transaction data cannot be tampered with. The data is on the block on the chain. There is a haveh value. If the block information is modified, the hash value also changes, and the hash value of all blocks behind it must also be modified to make a new chain. At the same time, the main chain is still in the transaction to generate blocks. Modify the post -chain must always be synchronized with the main chain to ensure the length of the chain. The price is too big, just to modify a piece of data.
8. What is the anti -DDOS attack
DDOS: By controlling many people's computers or mobile phones to allow them to access a website at the same time. Because the broadband of the server is limited, the influx of large amounts of traffic may make it possible The website may not work properly and suffer losses. But the blockchain is distributed, there is no central server, a node fails, and other nodes are not affected. Theoretically, more than 51%of nodes are attacked and problems will occur.
9. The definition of the main chain
Taking Bitcoin as an example, one block at a certain time allows 2 miners to dig it out at the same time, and then the first 6 block chain is the main chain is the main chain chain.
10. Single chain/multi -chain
Single -chain refers to the data structure that handles everything on a chain. The core essence of multi -chain structure is composed of public chains N sub -chains. There is only one, the sub -chain can theoretically there are countless pieces, each sub -chain can run one or more DAPP systems
11. Public -owned chain/alliance chain/private chain
Participate in the blockchain
Alliance chain: only allow alliance members to participate in accounting and query
Private chain: The permissions of writing and viewing are only in the hands of one organization.
12. The consensus layer data layer and other
The blockchain integrated structure has six: data layer, network layer, consensus layer, incentive layer, contract layer, application layer. Data layer: The first layer of the data belongs to the underlying technology; network layer: build a architecture of the blockchain network, which determines how to organize the user and the user through. Consensus layer: provides a set of rules that allow everyone to receive and store information. Incentive layer: Design incentive policies to encourage users to participate in the blockchain ecosystem; contract layer: generally refers to "smart contracts". It is a contract system that can be executed automatically and written according to its needs. Application layer: Applications on the blockchain, similar to the mobile APP similar to the previous distributed storage R