Blockchain test content

1. 1-contains a distributed database

2-The distributed database is the physical carrier of the blockchain, and the blockchain is the logical carrier of the transaction. All core nodes should contain the full of the blockchain data

3-The blockchain serializes the blocks according to time, and the blockchain is the only body of the whole network transaction data

4-The blockchain is only effective for adding, Invalid for other operations

5-public-private key verification based on asymmetric encryption

6-accounting node requires that Byzantine general problem can be solved / avoided

7-consensus progress is evolutionarily stable, that is, it will not collapse in the face of a certain amount of contradictory data of different nodes

8-consensus process can solve the problem of double spending

five characteristics of blockchain:
decentralized
e to the use of Distributed Accounting and storage, there is no centralized hardware or management organization, the rights and obligations of any node are equal, and the data blocks in the system are jointly maintained by the nodes with maintenance function in the whole system
thanks to the decentralization of blockchain, bitcoin also has the characteristics of decentralization [6]
openness
the system is open, in addition to the private information of all parties to the transaction is encrypted, the data of the blockchain is open to all, and anyone can query the blockchain data and develop related applications through the open interface, so the information of the whole system is highly transparent
autonomy
blockchain adopts consensus based specifications and Protocols (such as a set of open and transparent algorithms) to enable all nodes in the whole system to exchange data freely and safely in a de trusted environment, so that the trust in "people" is changed into the trust in machines, and any human intervention does not work
information cannot be tampered with
once the information is verified and added to the blockchain, it will be stored permanently. Unless more than 51% of the nodes in the system can be controlled at the same time, the modification of the database on a single node is invalid, so the data stability and reliability of the blockchain are extremely high<
anonymity
since the exchange between nodes follows a fixed algorithm, their data interaction does not need trust (the program rules in the blockchain will judge whether the activity is effective by themselves), so the counterparties do not need to let the counterparties generate their own trust by disclosing their identities, which is very helpful for credit accumulation.

2. Blockchain mainly solves the trust and security problems of transactions, so it proposes four technological innovations to solve this problem:
(1) distributed ledger, that is, transaction bookkeeping is completed by multiple nodes distributed in different places, and each node records complete accounts, so they can participate in monitoring the legitimacy of transactions, At the same time, they can testify together
different from traditional distributed storage, the uniqueness of distributed storage of blockchain is mainly reflected in two aspects: one is that each node of blockchain stores complete data according to block chain structure, while traditional distributed storage generally stores data in multiple copies according to certain rules. Second, the storage of each node in the blockchain is independent and has the same status, which relies on the consensus mechanism to ensure the consistency of storage, while the traditional distributed storage generally synchronizes data from the central node to other backup nodes[ 8]
no single node can record the account data separately, so as to avoid the possibility that a single bookkeeper is controlled or bribed to record false accounts. In theory, unless all the nodes are destroyed, the accounts will not be lost, so as to ensure the security of the account data
(2) asymmetric encryption and authorization technology, the transaction information stored on the blockchain is public, but the account identity information is highly encrypted, which can only be accessed under the authorization of the data owner, thus ensuring the data security and personal privacy
(3) consensus mechanism is how to reach a consensus among all accounting nodes to determine the validity of a record, which is not only a means of identification, but also a means of preventing tampering. Blockchain proposes four different consensus mechanisms, which are suitable for different application scenarios and achieve a balance between efficiency and security
the consensus mechanism of blockchain has the characteristics of "the minority is subordinate to the majority" and "everyone is equal", in which "the minority is subordinate to the majority" does not completely refer to the number of nodes, but also can be the computing power, the number of shares or other characteristics that can be compared by computers“ "Everyone is equal" means that when the nodes meet the conditions, all nodes have the right to put forward the consensus results first, and then directly recognized by other nodes, and finally may become the final consensus results. Taking bitcoin as an example, the workload proof is adopted. Only when more than 51% of the accounting nodes in the whole network are controlled can a nonexistent record be forged. When there are enough nodes in the blockchain, this is basically impossible, thus eliminating the possibility of fraud.
(4) smart contract, which is based on these trusted and tamperable data, can automatically execute some pre-defined rules and terms. Take insurance as an example. If everyone's information (including medical information and risk occurrence information) is true and reliable, it is easy to carry out automatic claim settlement in some standardized insurance procts

3. New technology is born to overthrow tradition! The law of human competition! Traditional instries do not realize how to start transformation! Of course, transformation is as painful as cutting meat

4. It depends on whether you invest. If you don't invest, you can make money by checking in every day. If you invest in the miner, the income will be higher.

5.

February 24 (Xinhua) the security of encrypted digital currency assets is completely based on the security of the private key of encrypted digital wallet, which is the only digital asset certificate. Once the private key is created, it cannot be modified and reset. As long as the private key is not lost, the asset will not be lost. Therefore, the whole security topic of encrypted digital assets is around the storage and use of private key. For the light wallet mode used in mobile terminal wallet, the security of user terminal private key storage is a very core and key problem. If the design is improper, it may lead to the loss of private key and the theft of assets

Jaxx is another well-known mobile cryptocurrency wallet, which has a large number of functions, including supporting multiple currency types, as well as the recently added digital currency exchange platform, allowing users to exchange bitcoin, Ethernet and erc20 tokens in the wallet

when we check the data backup mechanism of Jaxx, we find a major security vulnerability, which is more serious than bitcoin wallet. In fact, the private key stored in Jaxx can be stolen by hackers with little effort

6. It's known that it's a Ponzi scheme. Whether the blockchain can be traded or not can be verified by the owner himself. My mother-in-law can't persuade her to do so. She claims that she will go public. After many investigations, I found that the so-called VR maker, namely shede alliance, does not exist. The only two remaining companies are
: China dream shede Group Co., Ltd., registered in Hong Kong, After investigation, it has been cancelled in June, 18, and has no business activities since its registration. TIANCHAO Network Technology Co., Ltd., registered in Shanghai, has a registered capital of only 2 million yuan. Since 2016, it has no relevant financial statements and tax payment records. It is a leather bag company. The website of blockchain company is Io terminated and belongs to the domain name of British Indian Ocean. The maintenance fee is only a few hundred yuan a year
behind the high returns, there are opportunities to kill. Please think twice before you act. If you have invested, I will not say

7. Required, the remaining space is more than 1t, and the storage score of the miner is 10 points; The remaining space is 200g-1t, with 5 points; Less than 200g, 0 point. Therefore, it is recommended to buy 2T hard disk. If you buy 1t, the formatted capacity is less than 1t.

8. The reason why blockchain is deceiving is that many funds and air coins are under the banner of blockchain to recruit people to "cut leeks" to cheat money. Therefore, if you want to make investment, you should be careful of this. If you just want to know, I will some information I found to you. The following content comes from the network and my personal opinions, so it is only for your reference< The br / > Bobbi block is actually a panoramic life service application of block chaining, which applies block chain's underlying technology, artificial intelligence technology and panoramic VR space technology to build block chain ecosystem. It can be used for personal safety wallet tools (aggregating UnionPay, Alipay, WeChat payment, PayPal, and bank card payment). You can also set conditions for the other party to receive
for enterprises or groups, they can make use of the Bobbi panoramic blockchain as an intelligent ERP management system, put the enterprise's information and services into the panoramic space, and display their blockchain encrypted procts in the panoramic block. They can also establish their own blockchain distribution system through the intelligent contract, so as to truly realize the integrated operation of proct promotion and drainage, user experience and authentic proct sales
let's talk about my personal opinion. In recent years, blockchain has a trend of combining with different popular technologies, such as AI + blockchain, AI + blockchain and so on. This blockchain is panoramic technology + blockchain, so it is also an innovation to comply with the trend. Anyway, it seems that the concept of panoramic + blockchain is their idea, You can see the proct application or landing project corresponding to their concept. If the concept and proct application do not match, it is a gimmick. If not, it is not a fraud blockchain. The rest depends on your own understanding and judgment
very attentive answer, if you think it is helpful, please take it, thank you!