用故事讲区块链,一个故事解释区块链

曾经有一个叫做小明的小伙伴，他是一名会计，为了记录所有客户的账目，他有一本比较厚的账本，里面记录着每一笔交易，每一笔交易都要经过他的审核，他只有审核通过之后，才能记录到账本里，这样就能保证账本里的每一笔交易都是真实可靠的。

但是，当小明的客户越来越多，他的账本也越来越厚，他开始发现，审核账目的过程变得越来越繁琐，耗费了大量的时间和精力，他开始担心，如果有一天他出现问题，比如被病倒，账本中的交易记录可能不会得到保护，这会导致客户的交易记录可能会被篡改或者丢失。

小明在网上看到了一篇有关区块链的文章，他开始慢慢了解区块链的原理，发现它是一种可以保护数据的新技术。它能够将所有的交易记录存储在一个分布式的数据库中，所有的交易记录都是不可篡改的，而且数据库中的每一个节点都能看到所有的交易记录，这样就能保证数据的安全性和可靠性。

小明决定将自己的账本替换成区块链，他发现，使用区块链，他可以更快更安全地审核账目，而且不用担心数据的安全性，他可以放心地去休息，因为他知道，他的客户的交易记录是安全可靠的。

就这样，小明用区块链技术替换了自己的账本，他发现，这种技术不仅能够让他的工作变得更加高效，而且能够让他的客户的交易记录更加安全可靠。这就是区块链技术的好处，它可以让数据变得更安全，更可靠，并且能够帮助我们更快更安全地完成工作。

① Explain blockchain in vernacular

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Recently, various ICO financial scams have been blocked in China, but this does not hinder the vigorous development of blockchain technology. After all, technology is innocent and can bring benefits to people. As for how to use it, it depends on people to operate it. If the operation is good, you can recommend development. If the operation is not good, it is like the major ICO projects. Find some knowledge for Internet celebrities to conduct so-called illegal fund-raising and financial fraud.

After talking for a long time, what is blockchain? When it comes to blockchain, the first thing that comes to mind for many people is Bitcoin. We need to solve a problem. Bitcoin is a blockchain, but blockchain is not Bitcoin. Simply put, blockchain is distributed ledger technology (DLT), not a token. It has many characteristics, such as decentralization, traceability, and difficulty in tampering.

(1) Blockchain is a distributed database

First of all, this is a decentralized distributed architecture system. Therefore, having only one central server or node is not called a blockchain. For example, if you go to Taobao to buy a mobile phone, you and the seller are strangers and have no basis for trust. If you give the money to the seller first, the seller may block you by not delivering the goods, and then your mobile phone money will be gone. If the seller ships first, do you pay? It is possible that you do not pay the seller after receiving the goods, and one party may lose money anyway. At this time, a third-party guarantee is needed to solve the trust problem. Just like Alipay now, you give money to Alipay and the seller will deliver the goods. When you receive the goods, the seller will receive the money.

The above example is a centralized system because all guarantee work is handled by Bora, a third-party payment company. Suppose one day Alipay wants to tamper with data, neither buyers nor sellers can do anything because all authority is in the hands of one company.

At this time, a distributed database is needed. This third party is no longer Alipay, but thousands of monitors. When you buy a mobile phone on Taobao, you will shout to everyone that I am going to XXX to buy a mobile phone, and I paid XXX yuan. The other person will yell like everyone else. I collected XXX’s mobile phone bill and sent it over. In this way, everyone knows about this transaction and everyone is recording this transaction, so it is useless if one or two nodes have problems or malicious behavior, because most nodes have recorded this matter.

(B) Blockchain uses encryption technology to ensure data security

There are two important points here: 1. Crypto-enabled hash function 2. Asymmetric encryption.

If you are interested in specific concepts, you can go online, but people without basic knowledge may not be able to understand it, because these two points are too professional. In fact, if you only know the use of blockchain, you don’t need to have an in-depth understanding of it. It is also a technical concept. You just need to know that blockchain relies on these technical points to ensure data security and is not easilytamper. Of course, many people say that these two points can guarantee 100% non-tampering. I want to be a little conservative here. As an author who works in the security industry, I have always been skeptical about 100% security, so it may be more appropriate to call it difficult to be tampered with.

I will briefly introduce these two concepts and try to explain them clearly in plain English.

1. Cryptographic Hash Function

This is mainly used to verify the integrity of information. For example, I sent a message to the company leader saying that I was sick on Friday and needed to take a day off. At this time, a hash value will be generated based on the message I sent, such as: 123456. At this point, when the leader receives this message, a hash value is also generated. Because the content of the message I sent has not changed (it has not been tampered with), the hash value remains unchanged, still: 123456. This is if someone wants to tamper with this news and get sick on Friday and need to take a year off. At this time, the hash value will change, such as: 123489. That's when we learned our information had been tampered with.

2. Asymmetric encryption

It is mainly used for information encryption and authentication. It is actually two keys, one is called the public key and the other is called the private key. Public key encryption, private key decryption.

A public key is a key that everyone has. You own it, I own it. We can all encrypt with this key, but when decrypting it must be decrypted with my private key. If you don't have my private key, you can't decrypt it.

(C) The blockchain uses a consensus algorithm to reach consensus on new data.

The role of the consensus algorithm is to enable all nodes to reach a consensus on the new block. In other words, everyone must approve the new block.

For a centralized deployment system, this is simple, everything is controlled by the center, but in the distributed system of the blockchain, it is very complicated. For example, there are three nodes. A said he bought a mobile phone from XXX store and paid for it, B said he didn’t pay, and C said he didn’t pay enough. Then who do you listen to? What's more, blockchain technology is not as simple as three nodes, but a huge distributed system.

This is when a solution is needed. There is a corresponding problem in computer science called the "Byzantine Universal Problem" or "Byzantine Fault Tolerance" (BFT). This question was raised not because of Bitcoin, but because of a special background.

Early aircraft had three independent control systems. Why do we need three independent control systems? For example, in an emergency, there is a plane opposite. How to judge whether you should hide? If there is only one system, there is no choice, which is equivalent to centralized deployment. If the system breaks, you're dead. What if one of the two systems breaks? The good ones are said to hide, and the bad ones are said not to hide. The computer cannot judge the final result. Therefore, three independent systems are needed to support it, and the probability of two total failures is still very small. But this only takes into account injuries. What should I do if there is a malicious system? Is three enough? The answer is no, we need four systems to maintain consensus.

The use of blockchain is similar, because it is supported by a huge number of nodes, and each node is an independent system without interfering with each other. We can assume that failed nodes and malicious nodesThe number of points is limited, so it will not cause abnormal consistency in the data.

Related questions and answers: What is blockchain? What is the use?

Blockchain is a new computing paradigm and distributed infrastructure that uses fast chain data structures, distributed node consensus algorithms, cryptography and smart contracts based on automated script code to produce, verify, store and transmit data. It can also be said that blockchain is a distributed ledger technology that can provide a decentralized trust mechanism in a non-trust environment, allowing multi-party participants to conduct secure and trust-based transactions without intermediaries.

The core advantage of blockchain technology is decentralization. It can realize decentralized credit-based transactions in a distributed system where nodes do not need to trust each other by using data encryption, timestamps, distributed consensus and economic incentives. Point-to-point transactions, coordination and collaboration provide solutions to the common problems of high cost, low efficiency and insecure data storage in centralized institutions.

The fields of use of blockchain include digital currency, certificates, finance, anti-counterfeiting and traceability, privacy protection, supply chain, entertainment, etc. With the popularity of blockchain and Bitcoin, many related top domain names have been registered. It has had a relatively large impact on the domain name industry.

Related Q&A: Can you explain to me what a blockchain is in an easy-to-understand way?

Er Gazi is my friend since we were young, and we were naked in Hegou together. Later, I came to the city to study and work, and lived a life as a drifter in the north; he farmed at home and did some small business, and now he has a son and a daughter, and his life is safe. He envied my so-called "seen the world", and I envied his simple life without the pressure of mortgage loans. We have completely different and mutually enviable lives??

That day, Ga Zi came to me on WeChat and asked "District" What is a blockchain?" I was stunned for a moment, how could this idiot care about such an avant-garde word? I pretended to be calm and prepared to talk about the technical principles bit by bit, but I could see the confused expression of that idiot through the screen of my mobile phone. How to explain "what is blockchain" to people who have a little bit of Internet concepts and technical foundation? This seems to be a very thorny problem??

The village commissary interprets the core of blockchain (picture quoted from the Internet)

The core essence of blockchain is "decentralization", and almost all operating modes of blockchain operate around the concept of "decentralization". Once you understand what "decentralization" is, you can basically explain the question "what is a blockchain?" For Erga, of course, he must perform a version that he can understand.

“I said, Gazi, are you still open that canteen at the east end of the village?” Gazi answered yes. I decided to use this canteen as an example to explain the actual use of blockchain in modern business and financial models. Scenario, so that he can better understand what blockchain is.

"Are there still many villagers who take credit now? By the end of the year, some of the accounts cannot be remembered clearly, and there are still many defaulters or those who refuse to accept their accounts?" At this point, Ergazi got emotional and kept complaining. Nowadays, people's hearts are not as old as before, and business is difficult to do!

"Before youThe operation mode of the canteen is a typical centralized one. You grant credit to the villagers and you can take credit. All accounting is directly connected with our villagers through you, and you are the center of all accounting. " Ergazi said he understood and let me continue.

I said: "If you fail one day, then all the debts will become dead debts? It is estimated that it will be difficult to get back the IOUs written in black and white. Forget about remembering those accounts orally, but the decentralization of the blockchain can solve this problem very well. As long as the earth still exists, then the blockchain will remember that every account will exist forever." Erga became more energetic after hearing this.

The essence of the blockchain is "decentralization"

"The The essence is decentralization. Once someone takes credit from you, all the neighbors in the village will help you keep accounts. Because there are many nodes for accounting, it is neither easy to make mistakes nor others can refuse to pay, so everyone reaches a consensus. If someone maliciously fails to repay the debt, the whole village will know his character, and no one will be willing to have financial dealings with him in the future??"

At this point, Gazi was obviously a little excited. It seemed that he was I was really worried about the credit issue. Seeing that Gazi was interested, I also felt a small sense of accomplishment and continued: "Of course, the above is just an analogy. In fact, the blockchain does not really allow villagers to get paper. The pen helps you keep accounts, but it is done through the Internet and computer networking. "

At this time, Gazi was a little confused and asked: "Then what others bought from me, wouldn't everyone in the village know it? Then who would buy things from me? There is really no privacy at all. And you don’t have time to keep accounts here. Last year’s accounts are said to be this year’s. What if you keep procrastinating? "

"Okay, Gazi, your question is on point. "It seems that Gazi is not stupid at all, and he is very shrewd in doing business. I continued to explain: "So, the recording and transmission of this information are all done through encryption. What you see is a picture of numbers and English. String, and each account has a timestamp to record the time of occurrence, which cannot be relied on. "

Gazi had another question: "Is it possible that the people who owe the debt have a good relationship with the villagers, and they join forces to tamper with the accounting? Then you won’t be able to explain clearly at that time??”

“Gazi, that’s all you have, haha. "I understood Gazi's concerns and continued to explain: "The mechanism of the blockchain requires more than 51% of people to agree to tamper with a bill. Everyone has a degree of closeness and distance between them, and it is impossible for everyone to favor the same person. If it were a computer, more than half of the computers on the entire network would need to recalculate. This project would be so huge that it would be almost impossible to complete??"

In this way, through the actual situation of the canteen and combined with some scenes in life, Gazi understood What is in the blockchain: decentralization, distributed accounting, consensus mechanism, encryption mechanism, timestamps, and the characteristics of being difficult to tamper with.

Ergazi was silent for a moment, seeming to be digesting the example I just gave him. I don't know how much he can understand the example. Not long after, he sent me a voice message on WeChat: "Does the blockchain mean that I used to learn from the Internet?"All purchases and payments have to go through Jack Ma’s house. If there is a blockchain, can we directly trade with the seller? Anyway, the accounting is very safe. "

"Okay, Gazi, it's really clear at first glance. Blockchain is essentially a decentralized distributed ledger data cloud. Of course, it can be understood according to your understanding. "I'm very happy that Gazi can roughly appreciate the true charm of the blockchain. Fortunately, my words have not been in vain.

What is Bitcoin? (Picture quoted from the Internet)

"Then Bitcoin What is this thing again? What does it have to do with blockchain? "Gazi asked.

I thought about it briefly and decided to continue to explain to Gazi with the story of the canteen: "Your canteen, the villagers can't keep accounts for you for free all day long, right? Do you have to carry some during the holidays? This is the reward mechanism of the blockchain, and everyone who participates in bookkeeping may receive rewards. "

"Then what are the rewards based on? There has to be a rule, right? "Gazi asked very puzzled.

I explained: "Zhang San went to your store to borrow a pack of cigarettes on credit, but Li Si knew about it first and kept an account for you first, and then others knew about it. Keep accounts, then Li Si can get a small red flower as a reward ~ This small red flower is generated by the blockchain system and has no value in itself, so you do not need to pay any cost for this small red flower??"< p>“Can Bitcoin be spent as money? How is it different from the banknotes we usually spend? "Gazi continued to ask.

"Bitcoin is a digital encrypted virtual currency. In principle, it has no value itself like our banknotes. However, banknotes have a credit guarantee from the state, so they have value. Bitcoin is the value formed by consensus among Bitcoin network users, and it has tradable properties, so it can be used to carry value. "What is said here is a bit profound. I don't know if I can understand it.

I continued to explain: "Banknotes can be printed infinitely. If more are printed, inflation will occur. When we were young, popsicles worth 1 cent were very good. , now you can’t eat with 1 yuan. Of course, there are many factors that affect inflation. The number of Bitcoins is fixed, and there is no possibility of unlimited over-issuance. However, different people have different judgments on their value, and coupled with the influence of supply and demand and investor sentiment, their prices are always fluctuating. ”

What is the difference between Bitcoin price fluctuations and stocks?

“So is speculating in Bitcoin just like speculating in stocks? Can you understand it this way? "Gazi seems to know a lot.

"In fact, there are some similarities, but there are also big differences. "I continued Gazi's topic: "The price of stocks always fluctuates around the valuation of companies, and there is government supervision in the stock market. Bitcoin itself has no value. It is priced entirely based on supply and demand and player valuations. It grows wildly without any government supervision. Therefore, it may have higher risks and higher returns than stocks. "

In the end, Gazi revealed the real purpose of today. He asked me: "Can I invest in blockchain projects? ”

If you don’t go to the Three Treasures Hall for nothing, you will beA typical example of this. Despite a large circle, both blockchain and Bitcoin, in fact, the question he really cares about is "Is investment in blockchain projects reliable?" When these words came out, I was extremely shocked. Now The so-called blockchain investment projects have actually reached fourth- and sixth-tier cities and small towns!

Up to now, there are only three situations in investing in blockchain: mining, currency speculation, and so-called blockchain projects.

Mining and currency speculation are still the main lines of the blockchain (pictures quoted from the Internet)

The so-called mining is to obtain returns by purchasing mining equipment such as mining machines, mining virtual currencies, and then selling them for cash. . You can install the mining machine yourself, or you can find a mining pool to host it, but the core keys to profitability are "computing power" and "power consumption" as well as investment in equipment. With the sharp drop in the price of virtual currencies and the increase in mining difficulty, the current mining returns of many currencies are very unsatisfactory. Mining is obviously something only a very small number of investors who understand technology can do well, and my childhood friend Gazi obviously can’t do it.

As for "coin speculation", I have just introduced some differences between Bitcoin and stocks in the previous section. In principle, although they are both "buy low and sell high" operations, they are very different. Ordinary investors cannot determine the value of a virtual currency itself. The price is determined entirely by the relationship between supply and demand, which is somewhat similar to what we often call "market makers." On the other hand, the virtual currency trading market is extremely unstandardized, and fraud and hacker attacks often occur. The risk factor is much greater than investing in stocks. For the safety of my friends' funds, I am one of the ten thousand people who disagree with me and come to "speculate in coins"!

The "September Fourth Movement" stipulated that the issuance of virtual currency is illegal

In fact, in my opinion, most of the so-called investment projects in the market are essentially "illegal fund-raising" and "pyramid schemes." Some so-called blockchain investment projects attract investors into the circle through various packaging and inflammatory rhetoric, and then create the illusion of profitability by building a software and hardware ecosystem of issuing new coins + mining + currency speculation, and then finally run away. Our country's laws clearly stipulate that the issuance of virtual currencies is illegal.

Illegal pyramid schemes now wear the cloak of blockchain (picture quoted from the Internet)

And how to identify some pyramid schemes under the guise of blockchain? In fact, these pyramid schemes are also so-called Ponzi schemes, what we people often call "empty gloves." These so-called "direct sales" or "marketing" activities often have no actual products to circulate, and rely more on developing "downline" to ensure top-level profits. With the rise of the concept of blockchain, this MLM model has shown an intensification trend, and it even deceives people under the banner of state support for new technologies.

When Gazi asked, “Can blockchain projects be invested in?”, I realized the seriousness of the problem. Gazi is a typical young man from a small town, and his pursuit is his wife and children. But when faced with the attraction of "wealth", people often do inappropriate things. Mining and currency speculation are simply not suitable for him, let alone blockchain investment projects that are most likely "illegal financing" or "illegal pyramid schemes"!

I quickly called Gazi and conducted the above analysis carefully??

② Briefly explain what is blockchain

Blockchain is a A term used in the field of information technology. In essence, it is a shared database, and the data or information stored in it has the characteristics of "unforgeable", "full traces left", "traceable", "open and transparent" and "collectively maintained". Based on these characteristics, blockchain technology has laid a solid foundation of "trust" and created a reliable "cooperation" mechanism, which has broad application prospects.

On January 10, 2019, the Cyberspace Administration of China issued the "Blockchain Information Service Management Regulations". On October 24, 2019, during the 18th collective study session of the Political Bureau of the CPC Central Committee, General Secretary Xi Jinping emphasized that “blockchain should be used as an important breakthrough for independent innovation of core technologies” and “accelerate the development of blockchain technology and industrial innovation.” . "Blockchain" has entered the public eye and become the focus of society.

On December 2, 2019, the word was selected into the top ten buzzwords of 2019 by "Biwenqiezi".

(2) Use a simple story to analyze the blockchain Extended reading:

Blockchain financial application:

2016 Since the beginning of the year, major financial giants have also taken notice and launched blockchain innovation projects one after another to explore the possibility of applying blockchain technology in various financial scenarios. In particular, Puyin Group took the lead in pioneering the “blockchain+” standard digital currency.

The standard digital currency is an asset that has been identified, evaluated, confirmed, insured, etc. by a third-party organization and written into the blockchain through rigorous digital algorithms to form a standard correspondence between the asset and the digital currency. relationship, called a standard digital currency.

In order to realize the great leap forward development of blockchain finance, in order to promote the new development of China's economy, accelerate the circulation of global assets, and realize the dream of rejuvenation that generations of people have been striving for, Puyin Group will Puyin Blockchain Finance Guiyang Strategy Release Ceremony was held in Guizhou on the 9th;

At the meeting, the digital circulation of assets through blockchain, the blockchain financial transaction model, and the relationship between blockchain services and blockchain services will be discussed. The application of social public industries will be discussed. This conference will mark the beginning of the application of blockchain finance and the transformation and development of a new financial ecosystem.

③ The prototype of blockchain-distributed accounting

A short story to help you understand the prototype of blockchain-distributed accounting:

A group of friendly residents lived on a group of small islands. Over the long years, they used shells as a credit intermediary and used them as equivalent exchange items to exchange for the food they needed. A thousand years later, the island appeared A big man asked everyone to agree to use the leaves from his tree as the only credit intermediary.

Anyone who tried to resist was thrown into the sea to feed the fish, and the kind people were quickly tamed.

Slowly, the leaves in Dahan’s house became equivalent exchange items on the island. The islanders must first exchange items for leaves, and then use the leaves to exchange for other daily necessities. As the days passed, everyone had more and more leaves in their hands, but the things they bought were less and less. Except for the big man and his men, many people were living a tight life.

Until one day, one of the islanders drifted to another island and found that the exchange method on this island was different from that on his own island. They do not use leaves, but jointly keep accounts. All islanders keep their current accounts in a ledger, and all transactions are represented by numbers on the ledger. As long as it is approved by 6 people, everyone thinks the account is correct.

If this person wants to buy something, he only needs to debit it and take away the goods. This new method is simpler and more convenient than using leaves as intermediaries. If you choose this method, everyone on the island can trade freely without leaves. At the same time, because the accounts are public, everyone can check the bills, which eliminates the possibility of fraud.

This kind of joint accounting method has the shadow of Bitcoin and is also the prototype of blockchain technology-distributed accounting. The 6 people on the island are equivalent to 6 nodes. Each node maintains its own ledger, which records the transactions of the islanders on the island.

④ Several thrilling blockchain stories

After sending Emily to school yesterday, I hurried home. The sixth of every month is the day for our Class 10 scheduled investment. When I turned on the computer, I was shocked. The day before, Bitcoin was still trading sideways at around 7,300 US dollars. Why did it suddenly become 6,400 US dollars? I rubbed my eyes. That's right, the overnight drop was as high as 13%. Before, I subconsciously thought that it would break through the 7400 mark. I didn't expect that there is a principle in the bear market called "If it lasts for a long time, it will fall."

Of course, in the blockchain world, yesterday’s 13% drop is nothing new. We old leeks followed Li Xiaolai’s path to wealth and freedom and came to this “exciting” world. It has been more than a year, and although I haven’t seen the rainbow yet, I have experienced the wind and rain. During last year’s 94 policy, Bitcoin fell by 36% in a few days. At that time, I had money in Yunbi but I didn’t dare to buy it. Only now do I realize how stupid I was at that time. At that time, I really didn’t understand anything, not finance, blockchain, and investment. I only knew that Li Xiaolai was awesome, and the people who left comments under his column were awesome. I wanted to join them, and no one else. Stop me, whoever stops me, I will be in a hurry, this is the passionate All-in blockchain.

But precisely because of being too timid, there have been very few operations over the past year, and precisely because of the few operations, the losses have not been large. My own blockchain story is as plain as a glass of boiled water.

Yesterday I read an issue of Tencent’s “Talk to Strangers” about districts.A video program called Blockchain Story, in which three people were interviewed: Zeng Wen, a wage earner, Colorful Shenyu, a big boss in the cryptocurrency industry, and Liu Ke, a sophomore student.

Zeng Wen, a migrant worker with a junior high school education, first worked at Foxconn. He was so busy that he had to trot all the way to the toilet. He said that he was always bullied by others because he was too honest, and he did all kinds of hard work. Yes, but no money. Later, I met a girlfriend who treated him in every possible way just to lure him into a MLM organization. As a result, she lost all her parents’ hard-earned money of 60,000 yuan. She escaped from the MLM organization and was deceived into working in a rat barn. , the people behind use money to patch up the holes made by those in front, but naturally there will always be a day when the holes can’t be patched up. This has defrauded all the men, women, and children in the village. They owe a debt of 300,000 yuan, and they are so scared that they dare not go home during the New Year. Later, he thought that if he relied on part-time work, he would never be able to repay so much money in his life, so he was introduced to the blockchain by a friend again. In 2017, during the blockchain bull market, I earned 30,000 yuan a day at my peak. Within a few months, I suddenly became a millionaire, and the coins I bought increased tenfold or a hundredfold. Not only did he pay off all the money he owed before, but he also sent money to his parents, helped them buy rings, and bought the largest TV set in the village for his family. Of course I have reached a new "class". Taking the bus used to be too expensive, but now I take a taxi when I go out. I go to KTV to hire girls. I am romantic and happy. Happiness comes at a lightning speed. Who would have known that at the beginning of 2018, Bitcoin would drop from its highest price of $20,000 to just before liberation, and the myth of wealth creation would be broken so easily. Now he's back to his old self, but confident about the future. The host asked, where does your confidence come from? He said that he was trained when doing MLM. To do MLM, you must have positive energy.

Colorful Shenyu, a big figure in the currency circle, went to the library one day when he was in his first year of study and saw the news about Bitcoin. Then I skipped school and spent all day studying Bitcoin in my dormitory. The more I studied it, the more I liked it. I thought it was a new technology that would subvert the world. From then on, All in the blockchain, they were the first group of geek players, digging and selling coins by themselves. When he was 23 years old, he suddenly found that there were 100 million assets in his bank account. He was stupid, what should he do? ? How to spend 100 million? Go check the posts on Zhihu and read them one by one. In the end, you have so much money that you don’t know how to spend it, so you just go trash the place. You throw a party wherever you go and trash the place. After you spend the money, you’ll be fucking awesome. If it doesn't work, I have plenty of money. You can decide how much compensation I will pay.

Bitcoin is both a devil and an angel, occupying their lives. At the beginning, the price of Bitcoin was extremely low, ranging from a few dollars to dozens of dollars. It rose to hundreds of dollars, and then dropped rapidly after a few thousand dollars. It dropped so much that even my own mother didn’t recognize her, and she couldn’t even recover the cost of mining. The mine can only be closed. After being lost and confused for a month, he came back again. This time he went to Sichuan, Xinjiang, and Tibet to mine in remote places with cheap electricity. In those places, traffic was almost paralyzed, and he often had to face sudden mudslides. .

Seven yearsIt is a lifetime, from 2011 to 2018, exactly a lifetime. In this lifetime, Colorful Divine Fish has experienced many joys, sorrows and joys that his peers have never experienced. He has experienced too many storms in life. Now he is still a loyal fan of Bitcoin. He said that even if one day Bitcoin becomes zero, I will always collect some Bitcoins. It was Bitcoin that changed his life path. Otherwise, he would be an unknown programmer.

The last story is the most tragic, and the director deliberately placed Liu Ke in the finale. Liu Ke, a sophomore, failed to speculate on Bitcoin and is now alone in a foreign country, struggling to survive by doing drug experiments for hospitals. The reporter asked him, do you know that conducting drug experiments in hospitals is a high-risk job? He said, of course he knows that the higher the price, the more dangerous it is, but if you were me, you would do the same.

Liu Ke is a handsome-looking boy. If he had not embarked on the road of blockchain, he would be playing basketball on the playground with a bunch of girls cheering for him. He wiped the sweat from his face and turned to give the girls a chic pose or a charming smile.

Although his parents are not rich people, they run a small business at home and give him 1,000 yuan a month for living expenses. If he could study and study peacefully, he should have been able to graduate smoothly. But when the myth of blockchain wealth creation in 2017, the myth that he could double his money with 3,000 yuan in one night, made him lose control, so he took out loans on various platforms and used the loan money to invest. At that time, speculation Coins are like cash machines, no matter how you speculate, you can make money, and the word "risk" in his world disappears.

So he used 20 times the leverage to leverage greater wealth. He never imagined that the wealth would not be leveraged, and the nightmare was awakened. Creditors came one after another with all kinds of threats and inducements. He felt that he could no longer stay, so he thought of committing suicide. His parents had already persuaded him not to blindly speculate in coins, but he couldn't listen and hurt his parents' hearts again and again. Feeling very guilty and blaming himself, he did not commit suicide and had no choice but to flee to Cambodia. I don’t know when the days of running away like this will end.

After watching this video, I felt mentally uncomfortable for a long time. It can be said that there is no threshold for entering the blockchain world. Anyone can enter. You don’t need to understand finance or blockchain. You don’t need to know how to invest, even if you only have a few hundred yuan, you can enter. But now this industry is so unstandardized. Many people and many projects are here to cheat, prepare a white paper, and after a wave of increases, the banker makes money and runs away. The unlucky ones are the leeks bought later. So far, the blockchain is a zero-sum game. At this stage, no real hematopoietic function has been born. So the nature of the blockchain is similar to that of the rat warehouse. Those who get rich in the front are just making money from the leeks that enter later.

But investing is mine anywayThis is something we all have to face in this life. If we have never invested in this life, our understanding of human nature and society will never be complete. But investment only seems very simple. To invest well, you need to practice continuously.

⑤ How to interpret blockchain in the simplest way

Everyone hears the word blockchain every day recently, so what is blockchain? Explanations such as "distributed, difficult to tamper, and consistent storage" are too technical and dry. Let me give you some popular science here: Blockchain is mainly designed to solve the trust problem between individuals who do not trust each other.

To give a popular example: It is said that Lao Li and Lao Wang live in the same village. Lao Li is a little short of money recently and wants to borrow some money from Lao Wang. As for Lao Wang, he was worried about what would happen if he defaulted on the loan after borrowing money from Lao Li, so he called in the "highly respected" village chief. But thinking about it, the village chief couldn't be trusted either. The village chief had even stolen other people's sweet potatoes in the past! what to do?

The blockchain method is: After Lao Wang borrowed 1,000 yuan from Lao Li, he then used a loudspeaker to shout in the village, "I, Lao Wang, borrowed 1,000 yuan from Lao Li today. Everyone Record it quickly." So everyone in the village recorded it in their own account books and kept it carefully. This is good, Lao Li can't rely on him anymore. Even if there are dishonest people in the village, there are still many good people. Lao Li can't find everyone in the village to secretly erase his loan records. In this way, the blockchain solved the trust problem of borrowing money between Lao Wang and Lao Li, who did not trust each other.

Before the emergence of blockchain, how did we solve the problem of trust between individuals who did not trust each other? It's simple, just find a "witness" who is "highly respected" and trusted by both parties, such as the village chief in the story, such as Alipay between the buyer and seller, such as the notary office, etc. However, it is possible that such "witnesses" may not always be honest, so the blockchain simply allows everyone to act as a witness.

Lao Wang is relieved, but Lao Li has a headache! Lao Li has to wait until everyone in the village has recorded the money before he can get the money lent to him. There is no uncle or aunt in the family who is slower. Therefore, there is still a certain distance between blockchain and application, and efficiency issues need to be significantly improved.

Recall how you usually trade with others: you can choose a beautiful dress in a physical store, confirm that the other party’s clothes are of good quality, and the other party confirms that your money is real money. , then we will pay and receive the goods face to face.

What if we are thousands of miles apart and neither know nor trust each other but still want to trade? Then there needs to be a third party that we all trust, which is the so-called consensus mechanism. For example: you can complete the transaction through a third-party witness guarantee on Taobao. The money is first given to Alipay - Alipay collects the payment and lets the seller deliver the goods - the seller delivers the goods - you confirm receipt - Alipay then gives the money to the seller.

However, if this centralized organization does evil, Dad Ma willWhat should I do if my dad tears up the ledger and refuses to admit that you gave him the money, or joins forces with the seller to defraud you of your money?

Or maybe the government lends you 1 million, and finally pays you back by issuing extra currency. The 1 million shrinks to 10,000, and you bear the loss of inflation. What should you do? ?

Is there a third party that is not controlled by any government or organization, can complete arbitration in an open and transparent manner, has records that will not be tampered with, and has no risk of running away?

Don’t worry, our protagonist blockchain technology solves this problem - the transactions between you can be witnessed by everyone in this blockchain system, and everyone’s small ledger will be recorded Your deal. If B denies receiving money from A, or if A says that he borrowed 300 yuan, passers-by A, B, B, and D will question him. How exactly is it done?

1) The system issues a small ledger to everyone, so that everyone has the right to keep accounts. We call it distributed accounting.

2) In order to encourage everyone to help others keep accounts, the system code is set to reward tokens such as Bitcoin to the keepers. In order to prevent a group of people from being blocked in keeping accounts, the tokens are also set to There are only a limited number of A, B, C and D who need to be calculated through the mechanism specified by the system. Only the fastest and best calculation can obtain the right to keep accounts. After recording, it is broadcast to everyone through the system. Everyone copies the same ledger. This is obtained through calculation. The reward process is called mining, and passers-by A, B, C and D who keep accounts are the miners.

3) One day, A, who originally recorded the transaction, Game Over, but the ledger still exists in other people's ledgers. Neither A nor B can deny it. We have written in code how to arbitrate and distribute, without the need for banks, governments, enterprises and other centralized organizations to serve as third-party witnesses (decentralization), and the direct point-to-point (P2P) transaction method is called decentralization.

4) The system packages multiple transactions into blocks and links them in chronological order to become the final ledger that everyone has. This is the blockchain technology

In fact, the block chain The simple understanding of blockchain as a ledger is only the simplest interpretation. If each of its characteristics is separated, it can be applied in many fields.

Now the traditional financial industry, securities firms, and investment institutions are rushing to enter the Internet of Things, games, storage, copyright, anti-counterfeiting, credit reporting, payment, prediction markets (gambling, etc.), communities and many other fields. The exploration and application of blockchain has already begun.

The Internet allows everything to be connected. Can blockchain make everything connected trustworthy?

Let me explain the blockchain using the strange stones that are naturally transformed by heaven and earth:

All science, philosophy, morality... heaven and earth embrace itWith. Every thing and every culture is related to the Taoism of heaven and earth.

Blockchain naturally cannot escape the fate of heaven and earth: that is, smooth, random, infinite, and impermanent.

It is this strange stone, and the overall data movement on its surface. First, the whole is intangible. Second, the lines and points adhere to a pattern: the path of impermanence. That is to say, every line and every point they pursue is not a closed goal or a limited purpose. I can understand it better when I say this: when a painter paints a chicken, it has a purpose and an ending, while strange rocks, when created by nature, have no ending. Therefore, the phase is not closed, and the line and point data are not terminated. The technology of block connection is this way of destiny. Impermanence is invisible and has no end. (No centralization means formlessness, no closed form, no closed structure, no closed mind... just like "stone" to do things).

Confucius Lingshi Museum in Qufu, Shandong

Hello everyone, I am Pippi. I will use a few life examples to explain to you what blockchain is?

A decentralized, tamper-proof, distributed storage data block linking system that uses encrypted information as the link address is called blockchain

This thing is originally There are many high-tech composite products that cannot be simplified. No matter how simple it is, it takes a long paragraph, and it may not be clear.

The strict definition of blockchain refers to the design based on cryptography technology. Consensus mechanism, a distributed database technology in which multiple nodes in a peer-to-peer network jointly maintain a continuously growing, chained list ledger constructed of timestamps and ordered record data blocks. This technical solution allows any number of nodes participating in the system to calculate and record all information exchange data in the system over a period of time into a data block (block) through cryptographic algorithms, and generate the fingerprint of the data block for linking ( chain) and check the next data block, all participating nodes in the system jointly determine whether the record is true.

Blockchain is a general term for technical solutions similar to NoSQL (non-relational database). It is not a specific technology. Blockchain technology can be implemented through many programming languages ​​and architectures. . There are also many ways to implement blockchain. Common ones currently include POW (Proof of Work), POS (Proof of Stake), DPOS (Delegate Proof of Stake), etc.

The concept of blockchain was first introduced in the paper "Bitcoin: A Peer-to-Peer Electronic Cash System"Cash System", it is proposed that the author is an individual (or group) who calls himself Satoshi Nakamoto. Therefore, Bitcoin can be regarded as the first application of blockchain in the field of financial payments.

[Popular explanation]

No matter how big the system or how small the website, there is usually a database behind it. So who will maintain this database? Under normal circumstances, whoever is responsible for operating the network or system will maintain it. If it is a WeChat database, it must be maintained by Tencent's team, and Taobao's database must be maintained by Alibaba's team. Everyone must think that this approach is natural, but this is not the case with blockchain technology.

If we imagine the database as a ledger: Alipay, for example, is a typical ledger, and any change in data is an accounting type. We can think of database maintenance as a very simple accounting method. The same is true in the world of blockchain. Everyone in the blockchain system has the opportunity to participate in accounting. The system will select within a period of time, maybe within ten seconds, or maybe ten minutes, to select the person with the fastest and best accounting during this period. This person will do the accounting, and he will combine the changes in the database during this period with Changes in the ledger are recorded in a block. We can imagine this block as a page of paper. After confirming that the record is correct, the system will link (chain) the data fingerprint of the past ledger to this paper, and then This piece of paper is sent to everyone else in the entire system. Then the cycle starts over and the system looks for the next person who can do the accounting quickly and well, and everyone else in the system gets a copy of the entire ledger. This means that everyone in this system has exactly the same ledger. This technology is called blockchain technology, also known as distributed ledger technology.

Since everyone (computer) has exactly the same ledger, and everyone (computer) has exactly the same rights, there will be no problem due to a single person (computer) losing contact or going down. The entire system collapses. Since there are exactly the same ledgers, it means that all data is open and transparent, and everyone can see the digital changes in each account. Its very interesting feature is that the data in it cannot be tampered with. Because the system will automatically compare, it will consider the account books with the largest number of the same number as the real account books, and the small number of account books with different numbers as others are false account books. In this case, it makes no sense for anyone to tamper with their own ledger, because unless you can tamper with most of the nodes in the entire system. If the entire system has only five or ten nodes, it may be easy to do, but 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 of the computers in the world , otherwise it would be unlikely to tamper with such a large blockchain.

【RequiredElements】

Combined with the definition of blockchain, we believe that it must have the following four elements to be called a public blockchain technology. If it only has the first three elements, we will consider it a private area. Blockchain technology (private chain).

1. Point-to-point peer-to-peer network (peer-to-peer power, physical point-to-point connection)

2. Verifiable data structure (verifiable PKC system, non-tamperable database)

3. Distributed consensus mechanism (solve the Byzantine generals problem and double payment)

4. Nash equilibrium game design (cooperation is an evolutionarily stable strategy)
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[Characteristics]

Combined with the definition of blockchain, blockchain will realize four main characteristics: decentralized, trustless, Collectively maintained (Collectively maintained), reliable database (Reliable Database). And the four characteristics will lead to two other characteristics: open source (Open Source) and privacy protection (Anonymity). If a system does not possess these characteristics, it will not be considered an application based on blockchain technology.

Decentralized: The entire network has no centralized hardware or management organization. The rights and obligations between any nodes are equal, and the damage or loss of any node will not affect it. operation of the entire system. Therefore, the blockchain system can also be considered to have excellent robustness.

Trustless: Each node participating in the entire system does not need to trust each other for data exchange. The operating rules of the entire system are open and transparent, and all data contents are also public. , therefore within the rule range and time range specified by the system, nodes cannot and cannot deceive other nodes.

Collectively maintain: The data blocks in the system are jointly maintained by all nodes with maintenance functions in the entire system, and these nodes with maintenance functions can be participated by anyone.

Reliable Database: The entire system will be divided into databases so that each participating node can obtain a copy of the complete database. Unless more than 51% of the nodes in the entire system can be controlled at the same time, modifications to the database on a single node are invalid and cannot affect the data content on other nodes. Therefore, the more nodes and stronger computing power participating in the system, the higher the data security in the system.

Open source(Open Source): Since the operating rules of the entire system must be open and transparent, for the program, the entire system must be open source.

Privacy protection (Anonymity): Since nodes do not need to trust each other, there is no need to disclose their identities between nodes. The privacy of each participating node in the system is protected. protected.

[One of the meanings of blockchain: Solving the Byzantine Generals Problem]

The core problem solved by blockchain is not “digital currency”, but information asymmetry and inconsistency. Under a certain environment, how to establish a "trust" ecological system that satisfies the occurrence and development of economic activities. This problem is called the "Byzantine Generals Problem", also known as "Byzantine Fault Tolerance" or the "Two Armies Problem". This is a difficult problem faced when information machines interact in a distributed system, that is, any point in the entire network When nodes cannot trust the other party they are communicating with, how can they create a consensus basis for secure information exchange without worrying about data being tampered with. Blockchain uses an algorithmic proof mechanism to ensure the security of the entire network. With it, all nodes in the entire system can automatically and securely exchange data in a trustless environment. For more introduction, please see "Bitcoin and the Byzantine Generals Problem".

[The second meaning of blockchain: realizing cross-border value transfer]

At the beginning of the birth of the Internet, the earliest core problem to be solved was information production and transmission. We can transfer information through the Internet It can be quickly generated and copied to every corner of the world with a network, but it still cannot solve the value transfer and credit transfer. The so-called value transfer here refers to a method that everyone in the network can recognize and confirm, accurately transferring a certain part of the value from a certain address to another address, and it must be ensured that when the value is transferred, the original address is reduced The transferred portion, while the new address increases the value transferred. The value mentioned here can be a monetary asset, or some kind of physical asset or virtual asset (including securities, financial derivatives, etc.). The results of this operation must be recognized by all participating parties, and the results cannot be manipulated by any one party.

There are also various financial systems in the current Internet, and there are also many payment systems provided by government banks or third parties, but they still rely on centralized solutions. The so-called centralized solution is to put all value transfer calculations on a central server (cluster) through the endorsement of a certain company or government credit. Although all calculations are automatically completed by programs, this centralization must be trusted. person or institution. In fact, through centralized credit endorsement, credit can only be limited to certain institutions, regions or countries. It can be seen from this that the fundamental problem that must be solved is credit. So the priceThe core issue of value transfer is cross-border credit consensus.

In such a complicated global system, it is difficult to establish a global credit consensus system out of thin air. Due to the different political, economic and cultural conditions of each country, it is difficult for two countries to It is almost impossible for enterprises and governments to completely trust each other. This means that whether it is endorsed by the credit of individuals or corporate governments, even if the value exchange between countries can be completed, there will be huge time and economic costs. But in the long history of mankind, no matter how different the religion, politics and culture of each country are, the only thing that can reach consensus is mathematics (basic science). Therefore, it is no exaggeration to say that mathematics (algorithms) is the greatest common denominator of global civilization and the basis for the greatest consensus among human beings around the world. If we use mathematical algorithms (programs) as endorsement, all rules are based on an open and transparent mathematical algorithm (program), which can allow all people with different political and cultural backgrounds to gain consensus.

[Future Development]

The Internet will make global interactions closer and closer, accompanied by a huge trust gap. Currently, the existing mainstream database technology architecture is private and centralized. On this architecture, the problems of value transfer and mutual trust can never be solved. Therefore, blockchain technology may become the next generation database architecture. Through decentralized technology, it will be possible to complete the huge progress of mathematical (algorithm) endorsement and global mutual trust on the basis of big data.

As a specific distributed access data technology, blockchain technology uses multiple nodes participating in calculations in the network to jointly participate in the calculation and recording of data, and mutually verify the validity of their information. (anti-counterfeiting). From this point of view, blockchain technology is also a specific database technology. The Internet has just entered the era of big data, but from the current point of view, big data is still in a very basic stage. But when it enters the blockchain database stage, it will enter the big data era of real strong trust endorsement. All data here has acquired indestructible quality, and no one has the ability or need to question it.

Perhaps we are now at a major turning point - the early stages of a major transition that is almost as profound as the changes brought about by the Industrial Revolution. Not only are new technologies exponential, digital and combined, progress and changes, but more surprises may be ahead of us. In the next 24 months, the planet will grow more computing power and record more data than it has in all of history combined. In the past 24 months, this value increase may have exceeded 1,000 times. This digital data information is growing faster than Moore's Law. Blockchain technology will not only be used in the field of financial payments, but will expand to all current applications, such as decentralized Weibo, WeChat, search, renting, and even taxi-hailing software may appear.Because blockchain will allow humans to collaborate on a large scale in a trustless manner without geographical restrictions.

Blockchain is a technology based on which many applications have been produced, including all industry businesses related to data and information. Bitcoin is one of the most well-known applications. The popular explanation of blockchain is that if you buy a lipstick online, you first find the product you like and place an order with the seller. You first give the money to the intermediary platform. After the seller ships the goods and the buyer confirms receipt, the intermediary platform then transfers the money. Transfer it to the seller, because of the trust issue, both buyers and sellers rely on the intermediate platform, and the blockchain, as a decentralized distributed ledger database, focuses on removing this intermediate platform while solving the trust issue at the same time. In the blockchain, everyone has their own ledger to record everything that happens. If a seller takes money but does not deliver the goods during the transaction, this record will exist permanently and cannot be modified, and there is no need to interact with each other. To exchange information, the blockchain world will select the person's ledger that records the fastest and best quality at the same time node to copy, send and connect in series, and finally stack it up to form a block.

When everyone talks about virtual currencies, they often cannot do without the concept of blockchain. So what is the magic of blockchain?

Blockchain is an underlying technology, essentially a decentralized distributed ledger database. It sounds very high-end and out of reach, but it is actually very easy to understand.

For example, if you want to buy something on Taobao, the first thing you usually have to do is to open Taobao, find the product you want, place an order and pay the money to Taobao, which is the transaction intermediary. Taobao will pay the seller after receiving the goods and confirming receipt. This was originally just a transaction between me and the seller, but it has an additional "center", namely Taobao.

During the transaction process, this "center" has unlimited power and can even modify the bill at will. Therefore, the “center” often needs a strong backend to endorse it.

So, a man named Satoshi Nakamoto wanted to get rid of this center with infinite power. He wanted to create a decentralized system in which everyone is the center and everyone is the center. Have the authority to keep accounts. So, he created Bitcoin.

In the Bitcoin system, everyone has a small ledger to record every transaction that occurs. A transaction is only valid after being confirmed by a majority of people. If the seller doesn't deliver the goods, everyone's little ledger will record it, leaving him nowhere to escape.

At this time, you may have questions. Since it is just a public ledger, why is it called a blockchain? This involves the issue of consensus. The blockchain system is a system composed of many "centers". The entire blockchain belongs to all individuals participating in accounting. At this time, a new problem arose, a systemA system must be orderly to survive in the long run. If the bookkeeper can act recklessly regardless of the cost, it may happen that he originally just bought a mobile phone, but received a Tesla instead.

So, Satoshi Nakamoto invented a consensus method called PoW. This method increases the cost of bookkeeping for bookkeepers and prevents them from doing evil easily. PoW uses cryptography to require bookkeepers to compete for computing power to obtain accounting rights. The first bookkeeper to calculate the result can obtain the accounting rights of a block packaged from several transactions. At the same time, you will receive certain tokens as rewards. This is what we commonly call "mining".

Now that the bookkeeper has recorded a block containing several transactions, the system needs to be organized and sorted. It is impossible to have countless blocks distributed in the system in an orderly manner. So it is necessary to link all blocks end to end in chronological order. At this time, the blockchain was born. The core of blockchain is technology.

⑥ What is the concept of blockchain? Read it in three minutes!

On October 25, 2019, Xinwen Broadcast sent a very important signal: the country must vigorously develop blockchain. After that, blockchain has become an Internet celebrity, and the figure of "blockchain" is floating in the streets and alleys. In fact, many technology companies have already deployed blockchain technology.

Although blockchain is very popular, many people do not know much about blockchain.

What is blockchain?

Let’s first take a look at how Du Niang explained it. Network display: Blockchain is a new application model of computer technologies such as distributed data storage, point-to-point transmission, consensus mechanism, and encryption algorithms.

Why is blockchain called blockchain?

The blockchain is linked by blocks one by one, and the blocks are storage units one by one, which record the communication information of each block node. The blocks are much like the records of the database. Writing data every time creates a block. With the expansion of information exchange, one block continues with another, and the result is called a blockchain.

What are the characteristics of blockchain?

Blockchain mainly has the following characteristics:

1. Decentralization: In the blockchain system, every node has equal rights. and obligations, there is no central control here. Decentralization has well established trust relationships with each other. Although there is no central management organization, people can collaborate with each other and trust each other. This mainly applies blockchain distributed ledger technology.

2. Openness: Blockchain data is open to everyone. Except for some encrypted information that is not open, everyone canFind the data here.

3. Independence: The entire blockchain system does not rely on other third parties. All nodes can automatically and securely verify and exchange data within the system without any human intervention.

4. Security: Blockchain has a certain degree of security and cannot be tampered with. Because everyone in the blockchain system has the same ledger, if someone wants to tamper with it, it is possible to forge a non-existent record only if they control more than 51% of the accounting nodes. Of course, this is basically impossible. This is mainly due to the core technology of the blockchain: the consensus mechanism. The consensus mechanism has the characteristics of "the minority obeys the majority" and "everyone is equal".

5. Anonymity: Many people think that if the blockchain is so open and transparent, will we lose privacy? In fact, no, although the transaction information in the blockchain is open and transparent, the identity information of the account is encrypted and can only be accessed with authorization.

Now let me tell you a story to help you better understand the blockchain.

There are three people in the family, mom, dad, older brother and younger brother. Last year, my father was in charge of the family's account books. He was responsible for all the family's income and expenses alone.

However, on the day of Double Eleven, my mother, who has always been frugal, wanted to buy herself a beautiful piece of clothing on a certain online store. When she checked the account book, she found something was wrong. It stands to reason that except for some money deposited in banks and financial management, the whereabouts of the daily consumption money at home are all in this account book, but no matter how you look at it, it is wrong. Some consumption is clearly not recorded, but is recorded.

Later, my father took the initiative to confess that he couldn’t help but buy a pack of cigarettes.

Later, my mother changed her strategy and the whole family kept accounts. Everyone recorded their monthly consumption expenditure in their own account books. Whenever there was a transaction or consumption at home, my mother would shout, "Book it," and everyone would record the transaction in their own books. This is the decentralized accounting model, where everyone is the center and everyone has a ledger.

The previous accounting model for dad was centralized accounting. If dad wanted to do something alone, it would be difficult for anyone to see it. The decentralized accounting model has solved the problem of centralization very well. The disadvantage of bookkeeping is that it is very difficult for dad to tamper with the books.

For example, if my father wants to take some money from the ledger and secretly buy cigarettes, the amount of money is limited, and if he wants to take the money, he has to change the ledger, but he only tampered with his own ledger. No, he had to change the accounts of three people including himself. And this is undoubtedly more difficult than reaching the sky.

So, many times my father had the idea of ​​smoking, but he had no choice but to give up the idea due to the current situation.

Are blockchain and Bitcoin the same thing?

In fact, blockchain and Bitcoin are not the same thing. It is just the underlying technology of Bitcoin. Bitcoin is the first digital currency applied by blockchain.

In 2008, Satoshi Nakamoto first proposed the concept of blockchain. In the following years, it became a core component of the electronic currency Bitcoin, serving as a public account book for all transactions. Blockchain was first applied to Bitcoin.

The origin of blockchain is to solve the problem of trust, and one of the most successful applications of blockchain is digital currency. Bitcoin is arguably the most successful application of blockchain so far.

What are the applications of blockchain?

The application of blockchain is actually very wide. In addition to digital currency, the future applications of Bitcoin are still very extensive. Blockchain technology has been widely used in different industries. Such as product traceability, copyright protection and transactions, payment and settlement, Internet of Things, digital marketing, medical care, etc., promoting different industries to quickly enter the "blockchain+" era.

1. Payment and clearing: Blockchain can abandon the role of transit banks, realize point-to-point payment, reduce transit fees, and accelerate fund utilization.

2. Product traceability: For example, if we buy a piece of clothing on a certain store, we can see the past and present life of this piece of clothing.

3. Securities trading: Traditional securities trading requires the coordination of four major institutions, which is inefficient and costly. Blockchain technology can independently complete one-stop services.

4. Supply chain: Introducing blockchain technology into the supply chain system, synchronizing information within the system can control all links, better complete division of labor and collaboration, and facilitate subsequent accountability.

5. Intellectual property rights: With copyright on the chain, our photographic works, musical works, literary works, etc. will become our information, and the ownership of the information will be confirmed and become our property.

⑦ I just learned about it. Can anyone tell me what blockchain is and how to explain blockchain technology in a simple way?

The way in which everyone keeps accounts together is also called "distributed ” or “decentralized” because everyone keeps accounts and the accuracy of the accounts is determined by program algorithms rather than an authoritative organization.

This is the blockchain. The core is finished. The blockchain is as simple as a common ledger

The six core algorithms of blockchain technology:

Blockchain Core Algorithm 1: Byzantine Agreement

The story of Byzantium goes like this: The Byzantine Empire has huge wealth, and its 10 neighboring countries have been around for a long time, but Byzantium’s high walls stand tall. It was so impregnable that no single neighbor could successfully invade. Any invasion by a single neighbor will fail, and it is also possible that it will be invaded by 9 other neighbors. byzantine emperorThe country's defense capabilities are so strong that at least half of its ten neighbors must attack at the same time to be able to break through. However, if one or several of the neighbors agree to attack together, but betrayal occurs during the actual process, then the invaders may all be annihilated. So each party acted cautiously and did not dare to trust its neighbors easily. This is the Byzantine Generals Problem.

Blockchain Core Algorithm 2: Asymmetric Encryption Technology

In the above-mentioned Byzantine Agreement, if several of the 10 generals initiate messages at the same time, it will inevitably cause chaos in the system. As a result, each has its own attack time plan, making it difficult to coordinate actions. Anyone can launch an offensive message, but who will send it? In fact, this only requires adding a cost, that is: only one node can spread information within a period of time. When a node sends a unified attack message, each node must sign and stamp the message from the initiator to confirm their identity.

Blockchain Core Algorithm Three: Fault Tolerance Issues

We assume that in this network, messages may be lost, damaged, delayed, and sent repeatedly, and the order in which they are received is different from the order in which they are sent. Inconsistent. In addition, the behavior of nodes can be arbitrary: they can join and exit the network at any time, they can discard messages, forge messages, stop working, etc. Various human or non-human failures may also occur. Our algorithm provides excellent fault tolerance for a consensus system composed of consensus nodes. This fault tolerance includes both security and availability, and is applicable to any network environment.

Blockchain Core Algorithm Four: Paxos Algorithm (Consistency Algorithm)

The problem solved by the Paxos algorithm is how a distributed system can reach agreement on a certain value (resolution). A typical scenario is that in a distributed database system, if the initial state of each node is consistent and each node performs the same sequence of operations, then they can finally obtain a consistent state. In order to ensure that each node executes the same command sequence, a "consistency algorithm" needs to be executed on each instruction to ensure that the instructions seen by each node are consistent. A general consensus algorithm can be applied in many scenarios and is an important issue in distributed computing. There are two models for node communication: shared memory and message passing. The Paxos algorithm is a consensus algorithm based on the message passing model.

Blockchain Core Algorithm Five: Consensus Mechanism

The blockchain consensus algorithm is mainly proof of work and proof of equity. Taking Bitcoin as an example, in fact, from a technical point of view, PoW can be regarded as reused Hashcash. Generating proof of work is a random process in terms of probability. To mine a new confidential currency, when generating a block, all participants must agree, and the miner must obtain PoW proof of work for all data in the block. At the same time, miners must constantly observe and adjust the difficulty of this work, because the network requirement is to generate a block every 10 minutes on average.

Blockchain Core Algorithm 6: Distributed storage is a kind of data storageTechnology uses the disk space on each machine through the network and forms these dispersed storage resources into a virtual storage device, and the data is dispersedly stored in every corner of the network. Therefore, distributed storage technology does not store complete data on each computer, but splits the data and stores it in different computers. It's like storing 100 eggs, not in the same basket, but in different places. The total sum is 100. If you want to know more, you can use the Internet search, Internet search results - little knowledge

⑧ Blockchain story - 9 - RSA algorithm

RSA

Diffie and Herman perfectly solved the problem of key distribution. From then on, exchanging keys was very simple. Alice and Bob could exchange a key just by shouting on the loudspeaker in the village. But the encryption method is still symmetric encryption.

Although the DH protocol is convenient for exchanging keys, it still has some unsatisfactory troubles. Alice still has to yell with Bob for a long time before they can generate the key. When Alice wants to exchange keys, if Bob is sleeping, Alice's love letter still cannot be sent.

In their paper, Diffie and Herman pointed out the direction for future encryption methods. Designing asymmetric encryption through one-way functions is the ultimate solution. The so-called asymmetric encryption means that one key is used to close the lock and another key is used to open the lock. The two keys are different. A locked key cannot open the lock. The key to unlock the lock cannot close the lock.

Three scientists from MIT, they are Ron Rivest, Adi Shamir and Leonard Adleman , they read the paper by Diffie and Herman, were deeply interested, and began to study it. The algorithm that Diffie and Herman failed to figure out was born from the hands of the three of them.

In 2002, these three masters won the Turing Award for the invention of RSA. But don’t think that RSA is all they have. These three are real masters, and each of them has a fruitful academic career. Let us look up and explore the heights of the masters.

Leviste also invented the RC2, RC4, RC 5, RC 6 algorithms, as well as the famous MD2, MD3, MD4, and MD5 algorithms. He also wrote a book called "Introduction to Algorithms". Programmers have worn out countless brain cells on this book.

Shamir invented Feige-Fiat-ShamirAuthentication protocol, differential cryptanalysis was also discovered.

Aardman is even more legendary. He pioneered the DNA computing theory and used DNA computers to solve the "traveling salesman" problem. His student Cohen invented the computer virus, so he is considered the grandfather of computer viruses. He is also a master-level expert in AIDS immunology and has made outstanding contributions in every aspect such as mathematics, computer science, molecular biology, and AIDS research.

In 1976, all three were working at MIT's Computer Science Laboratory, and they formed a perfect team. Leviste and Summer are computer scientists who constantly come up with new ideas, and Aardman is an extremely skilled mathematician who can always find problems for Leviste and Summer.

A year later, in 1977, Leviste was lying on the sofa sobering up after a party. He tossed and turned, unable to fall asleep. Half asleep and half awake, before vomiting, a bolt of lightning suddenly struck his mind, and he found a way. Overnight, he wrote the paper. The next morning, he handed the paper to Aardman, and Aardman could no longer find any mistakes this time.

In terms of the name of the paper, these three people were really gentlemen and modest. Rivest named it Adleman-Rivest-Shamir, and the great Adleman asked that his name be removed, as it was Rivest's invention. The final result of the dispute was that Aardman's name was listed third, so the algorithm became RSA.

The RSA algorithm is based on a very simple fact of number theory: it is very easy to multiply two large prime numbers, but it is extremely difficult to factor the product, so the product can be made public and used as Encryption key.

For example, if you choose two prime numbers, one is 17159 and the other is 10247, the product of the two numbers is 175828273. The product 175828273 is the encryption public key, and (17159, 10247) is the decryption private key.

The public key 175828273 is available to everyone, but to crack the ciphertext, you need to decompose 175828273 into 17159 and 10247, which is very difficult.

When RSA was announced in 1977, mathematician and popular science writer Martin Gardner published a public key in Scientific American magazine:

114 381 625 757 888 867 669 235 779 976 146 612 010 218 296 721 242 362 562 842 935 706 935 245733 897 830 597 123 563 958 705 058 989 075 147 599 290 026 879 543 541

Martin offers a reward to readers to crack this public key. It took 17 long years, but on April 26, 1994, a group of 600 enthusiasts claimed to have found the private key. The private key is:

p: 3 490 529 510 847 650 949 147 849 619 903 898 133 417 764 638 493 387 843 990 820 577

q: 32 769 132 993 266 709 549 961 988 190 834 461 413 177 642 967 992 942 539 798 288 533

This 17-year cracking only targets 129-bit public keys. Today RSA already uses 2048-bit public keys. Public key, which requires almost all the computing power of computers around the world and takes billions of years to crack.

The security of RSA relies on large number decomposition, but whether its cracking difficulty is equivalent to large number decomposition has not been theoretically proven, because it has never been proven that cracking RSA requires large numbers. Number decomposition.

RSA still has weaknesses. Because it performs large number calculations, the fastest RSA is many times slower than ordinary symmetric encryption, whether implemented in software or hardware. Speed ​​has always been a drawback of RSA. Generally only used for small amounts of data encryption.

RSA also has a weakness, which will be mentioned below.

In cryptography, American scholars are very busy and have achieved results one after another. But Britain, the old empire, was not without its achievements in cryptography. After all, it was the hometown of Turing, the country where Turing led cryptographers to defeat the German Ingmar encryption machine at Bletchery Park.

The British also invented RSA, but it was buried.

In the 1960s, the British military was also troubled by the problem of code distribution. In 1969, cryptographer James Ellis was working for the military when he was approached about the problem of key distribution. He came up with an idea to use a one-way function to implement asymmetric encryption, but he couldn't find the function. Many talented people from GCHQ joined in to find the one-way function. But three years have passed, and these smart heads have not gained much. Everyone is a bit disappointed.Frustrated, does such a single function exist?

Often at this time, a newborn calf is needed to save the day. Cox is a brave calf. He is a young mathematician, very pure, the kind who is determined to devote himself to the Muse. Although he was young, he had a huge advantage. At that time, he knew nothing about the one-way function problem and had no idea that his teachers had achieved nothing in three years. So he rushed into the mine formation ignorantly.

Faced with such a dangerous mine array, Cox almost jumped over it. It only took half an hour to solve the problem. Then he went home from get off work. He didn't take it too seriously. It was just a job assigned by the leader. It was nothing more than serving tea, pouring water, sweeping the floor and solving math problems. Finish it early. You can also buy freshly baked bread on the way home. He had no idea he was making history. Cox was such a pure mathematician that he later felt a little embarrassed when he heard the praise from his colleagues. In his eyes, mathematics should be, as Hardy said, a useless knowledge, but he used mathematics to solve specific problems, which is shameful.

Unfortunately, Cox's invention was too early. The computing power of computers at that time was too weak and could not realize asymmetric encryption and decryption. Therefore, the military does not apply asymmetric encryption algorithms. James and Cox developed the theory of asymmetric encryption to perfection, but they could not tell it. The military required that all work must be kept secret, and they could not even apply for a patent.

Although the military has very strict confidentiality requirements on work results, it does not care much about the work results themselves. Later, the British Communications Headquarters discovered the American RSA algorithm and thought it was great. They simply forgot about the James-Cox RSA. While the communications headquarters was amazed, they dug through their knowledge base and discovered that their employee Cox had already invented an algorithm similar to RSA. Bureaucracy is really a good friend of mankind. It can always create all kinds of jokes for people, although its original intention is to create authoritarianism.

Cox didn't mind this. He even said: "Just bury it. I don't want to be an Internet celebrity. Why do I need fans? Can those fans eat it?" Original words That's not the case, but the meaning is basically the same.

Diffie made a special trip to the UK to meet James in 1982. The two cherished each other. It was really a time when heroes met. It's a pity that James still couldn't reveal their research on RSA. He only told Diffie: "You are doing better than us." Scientists from all over the world can compare who is better, but it is difficult for bureaucrats from all over the world. There was no distinction between them in terms of who was more arrogant.

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⑨ Briefly explain what blockchain is and give an example!

For example:
The village chief’s conspiracy has been exposed! Who did it? Be bold!

It is said that the village chief of Maoxian Village, Mr. Wang, is a symbol of power in the village and is highly respected.

Every household in the village has transactions with each other. For the sake of fairness and justice, every household in the village must ask Village Chief Wang as a guarantee and record the information in his account book, but they must charge 1% of the transaction amount. , everyone is willing to trust him.

Suddenly one day, it was discovered that Village Chief Wang had accepted bribes from one party and maliciously tampered with the account books, causing serious losses to the other party.

All the villagers angrily decided to abolish his rights. Some villagers suggested that we all have an account book in the future. When a transaction occurs, we will shout at the entrance of the village. More than 51% of the villagers confirmed this transaction information. It will be regarded as passed, and the village’s account books will be open and transparent from now on.

The ledger of each villager is a block. Someone shouts at the entrance of the village, and everyone connects to confirm the ledger information is a chain. The combined system is a blockchain system. (Borrowing an example from the Zambi community)

⑩ What is blockchain and what family members does it have

Simply put, blockchain is a decentralized system. Take the "ledger" as an example. The traditional "ledger" is controlled by a center, but the blockchain "ledger" has no center. Everyone involved can record the "ledger".

Blockchain generally refers to public blockchains, family members also have private blockchains, and industry blockchains.

Blockchain technology provides a fair platform for the public. The editor believes that the application scope of blockchain technology will become wider and wider.

Finally, readers and friends who have any opinions about blockchain are welcome to leave a message.