Is blockchain a database
blockchain is a new application mode of distributed data storage, point-to-point transmission, consensus mechanism, encryption algorithm and other computer technologies. Blockchain is an important concept of bitcoin,
in essence, it is a decentralized database. At the same time, as the underlying technology of bitcoin, it is a series of data blocks generated by using cryptographic methods. Each data block contains a batch of information of bitcoin network transactions, Used to verify the validity of its information (anti-counterfeiting) and generate the next block
extended data
most blockchain public chains are limited by scalability. The biggest feature of blockchain technology is decentralization, which requires that all accounts in the network need to deal with the accounting process. Distributed accounting has high security, low misoperation rate, political neutrality and correctness
however, blockchain technology embraces these features at the same time, sacrificing scalability, unable to meet the personalized supervision, and slightly insufficient in protecting data privacy. Moreover, with the increase of the number of ledger, the interaction delay will increase exponentially, that is to say, the more ledger in the blockchain network, the higher the delay
The strict definition of blockchain refers to the distributed database technology that multiple nodes in peer-to-peer network jointly maintain a continuously growing list ledger constructed by time stamp and orderly record data blocks through consensus mechanism based on cryptography technology. This technical solution allows any number of nodes in the participating system to calculate and record all the information exchange data in the system in a period of time to a data block through cryptography algorithm, and generate the fingerprint of the data block for linking the next data block and checking. All participating nodes in the system jointly determine whether the record is true
blockchain is a technical solution similar to NoSQL (non relational database). It is not a specific technology, and can be implemented through many programming languages and architectures. There are many ways to realize blockchain, including pow (proof of work), POS (proof of stake), dpos (delegate proof of stake), etc
the concept of blockchain was first proposed in the paper "bitcoin: a peer-to-peer electronic cash system" by indivials (or groups) who call themselves Satoshi Nakamoto. Therefore, bitcoin can be regarded as the first application of blockchain in the field of financial payment
< H2 > [popular explanation]no matter how big the system or how small the website is, there is a database behind it. So who will maintain this database? In general, who is responsible for the operation of the network or system, then who is responsible for the maintenance. If it is wechat database, it must be maintained by Tencent team, and Taobao database is maintained by Alibaba team. We must think that this way is natural, but blockchain technology is not
if we think of the database as a book, for example, Alipay is a typical account book. Any change of data is bookkeeping. We can think of database maintenance as a very simple way of accounting. In the world of blockchain, everyone in the blockchain system has the opportunity to participate in bookkeeping. The system will select the fastest and best bookkeeper in a period of time, maybe within ten seconds or ten minutes. The bookkeeper will record the changes of the database and the account book in a block. We can think of this block as a page. After the system confirms that the records are correct, the system will record the changes of the database and the account book in a block, It will link the fingerprint of the past account book to this paper, and then send this paper to everyone else in the whole system. Then, over and over again, the system will look for the next person with fast and good bookkeeping, and everyone else in the system will get a of the whole ledger. This means that everyone as like as two peas in the system is called Blockchain. It is also called distributed account technology. P>
as like as two peas (computer) have identical accounting books, and everyone has the same rights, they will not collapse e to the loss of contact or downtime of a single person. As like as two peas, the data is transparent and everyone can see what changes are in every account. Its very interesting feature is that the data can't be tampered with. Because the system will automatically compare, it will think that the same number of books with the largest number are real books, and a small number of books with different numbers are false books. In this case, it's meaningless for anyone to tamper with his own account book, because unless you can tamper with most nodes in the whole system. If there are only five or ten nodes in the whole system, it may be easy to do so. However, if there are tens of thousands or even hundreds of thousands of nodes and they are distributed in any corner of the Internet, unless someone can control most computers in the world, it is unlikely to tamper with such a large block chain
< H2 > [elements]combined with the definition of blockchain, we think that we must have the following four elements to be called public blockchain technology. If we only have the first three elements, we will consider it as private blockchain Technology (private chain)
1, peer-to-peer network (power equivalence, physical point-to-point connection)
2, verifiable data structure (verifiable PKC system, non tampering database)
3, distributed consensus mechanism (Solving Byzantine general problem, solving double payment)
4 Game design of Nash equilibrium (cooperation is the strategy of evolutionary stability)
combined with the definition of blockchain, blockchain will realize four main characteristics: decentralized, trustless, collective maintenance and reliable database. And the other two will be derived from the four characteristics Features: open source Privacy. If a system does not have these characteristics, it can not be regarded as an application based on blockchain technology
Decentralized: there is no centralized hardware or management organization in the whole network. The rights and obligations of any node are equal, and the damage or loss of any node will not affect the operation of the whole system. Therefore, it can also be considered that the blockchain system has excellent robustnesstrustworthiness: there is no need to trust each other when participating in the data exchange between each node in the whole system. The operation rules of the whole system are open and transparent, and all data contents are also open. Therefore, within the specified rule range and time range of the system, nodes cannot and cannot cheat other nodes
collective maintenance: the data blocks in the system are maintained by all the nodes with maintenance function in the whole system, and these nodes with maintenance function can be participated by anyone
reliable database: the whole system will enable each participating node to obtain a of the complete database in the form of sub databases. Unless more than 51% of the nodes in the whole system can be controlled at the same time, the modification of the database on a single node is invalid, and the data content on other nodes cannot be affected. Therefore, the more nodes and computing power in the system, the higher the data security in the system
Open Source: since the operation rules of the whole system must be open and transparent, the whole system must be open source for the program
Privacy Protection: since there is no need to trust each other between nodes, there is no need to disclose the identity between nodes, and the privacy of each participating node in the system is protected
bitcoin trading platform has many running platforms, such as mtgox in Japan, bitcoin in China and so on
therefore, investors need to choose a reliable bitcoin trading platform. The reference factors are: 1. The longer the running time, the better; 2. The bigger the instry reputation, the better; 3. The larger the team size, the better; 4. Being able to visit<
it is suggested that China choose "fire coin net", which is cooperated by Wukou School of finance of Tsinghua University. Sequoia Capital has invested 10 million US dollars; The choice of coinbase in foreign countries is an important choice for Silicon Valley banks to invest.
College Students' innovation and entrepreneurship ideas include printing and ing services, leisure errands, school leisure food stores, college students' Tutoring instry, and online stores 1. Printing and ing service in fact, many schools have printing and ing stores. It seems that the market is saturated, but in fact, there is still a lot of space. Especially in the graation season, students have to print various reports, resumes and other information. The key to starting a business is to find the right location 5. Setting up shop on the Internet the sales volume of health care instry on the Internet is even more considerable than that of books and music. Buying daily necessities on the Internet is often favored by people because it can avoid the curious eyes of people on the street and face the situation of salesmen extended materials precautions 1, risk perception the risk perception of entrepreneurs depends on the entrepreneur's self-confidence, independent of plan, desire for control and other factors. Only those who have the courage to take risks can meet the challenges, invest their time, energy and financial resources and bear the possible losses 2. Alertness is also called entrepreneur early warning, which is used to reflect the ability of entrepreneurs to find out whether market opportunities exist or whether they have value. When one person has insight into the value of a resource while others don't, the warning has already appeared
Internet plus is an outdated word. Who is still talking about this word? p>
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the half hanging teacher in Colleges and universities, who couldn't find a good job in those years, was reluctant to bear hardships and went to the school to be a teacher, and then gave all kinds of advice, which is called "mistaking the children". What kind of entrepreneurship competition is also a laughing matter. All kinds of old ideas are on the table. They have no experience in social work. How can they talk about entrepreneurship? Of course, colleges and universities also have strong teachers, or academic strong, they will not talk about entrepreneurship with you. Either I have worked outside for a long time, worked as a leader, and become a teacher; Another is to realize financial freedom early. What the three groups do not do is Internet plus, because the word is out of date. p>
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ZF officials declined to comment
< / OL >
Why do I say this word is out of date? Go and see what is the hot field of venture capital, that is, the so-called tuyere
1, AI, has been fried for many years. This year,
2 is specially
2 and share the economy. Now it is in the red sea state. It can be regarded as the Internet Plus +
3, block chain technology
4, lithium battery and new energy vehicle, and is beginning to mature. p>
5. Fintech, Alibaba has long said that it is not engaged in Internet finance, but copied a foreign word, called financial technology company
the level of judges in the entrepreneurship competition is too low. Even if college students win the championship in the competition, they are in the wrong direction
if you want to start a business competition, you have to invite angel investors, PE, VC, at least those who have been in these companies, or else you are going to have a family
distinguish blockchain from ordinary database;, The main point is that the specific rules for putting data into the database are different. In other words, it can not conflict with other data already in the database. It is only added, immutable, and the data itself is locked to an owner (which can be owned). It is replicable and available. Finally, everyone agrees that the state of data in a decentralized database is compliant.