The failure of defining blockchain
blockchain is a new application mode of distributed data storage, point-to-point transmission, consensus mechanism, encryption algorithm and other computer technologies
the so-called consensus mechanism is a mathematical algorithm to establish trust and obtain interests between different nodes in the blockchain system
in a narrow sense, blockchain is a kind of chain data structure that combines data blocks in chronological order in a sequential way, and it can not be tampered with and forged by cryptography
broadly speaking, blockchain technology is a new distributed infrastructure and computing method, which uses blockchain data structure to verify and store data, uses distributed node consensus algorithm to generate and update data, uses cryptography to ensure the security of data transmission and access, and uses intelligent contract composed of automated script code to program and operate data< Advantages:
1) the algorithm is simple and easy to implement
2) there is no need to exchange additional information between nodes to reach a consensus
3) it takes a lot of cost to destroy the system< Disadvantages:
1) waste of energy
2) it is difficult to shorten the block confirmation time
3) the new blockchain must find a different hash algorithm, otherwise it will face bitcoin attack
4) it is easy to generate bifurcation and needs to wait for multiple confirmations
5) there is no finality, and checkpoint mechanism is needed to make up for it.
Bitcoin has opened the era of blockchain 1.0, which is characterized by providing a different way of thinking for value transfer, that is, value transfer no longer depends on centralized institutions such as banks. During this period, as more and more people were familiar with bitcoin, many people began to learn from the idea of bitcoin, so a large number of counterfeit coins appeared
the reason why these counterfeit coins are called "counterfeit coins" is that their source code is similar to that of bitcoin, and there is no substantive breakthrough. They also have the shortcomings of bitcoin, and there is no breakthrough improvement. However, people do not have the problem of bitcoin. Many people in the bitcoin community hope to solve these problems through a variety of technical means, so as to make the bitcoin system perfect
Among them, there is a Russian teenager named vitalik buterin, who is also eager to make up for the shortcomings of bitcoin system as soon as possiblefirst, you play games in a lively way, while others play games as gatekeepers
when he was 13 years old, he was a typical Internet addict, addicted to world of Warcraft. One day, the game company of world of Warcraft suddenly cancelled his favorite warlock "life siphon" skill. He was very angry and contacted the company many times to restore the skill. However, the game company did not agree
as a result, Butlin began to reflect that in Internet games, players, as participants, are actually very weak. The strong ones are game developers, who are the center of a game. Has the final say that the game player has no say what the developers want to do, and can only choose to accept or leave passively. p>
Butlin realized the disadvantages of centralization through "world of Warcraft", so he began to look for ways to break the centralization. Butlin realized bitcoin from his father, a programmer, and became so interested that he decided to give up the aura of a famous university and drop out of the University of Waterloo to travel around the world to exchange and learn with blockchain enthusiasts all over the world
at that time, bitcoin enthusiasts were going all out to add more functionality to bitcoin and build bitcoin 2.0. But Butlin believes that the establishment of a new programming language is bitcoin's top priority. So, at the age of 19, Butlin wrote a new white paper, which is the rudiment of Ethereum white paper. Butlin mentioned in the white paper
: he hopes to create a variety of applications based on the common programming language, such as social networking, trading, games... These ideas have been strongly echoed by the bitcoin community, and more and more people have joined in the design of Ethereum. Finally, this project was named "Ethereum" by Butlin, because "Ethereum" is a kind of material that has not been confirmed under scientific theory, implying Butlin's expectation for the project
in June 2015, Ethereum officially released
in the next two years, Ethereum's cryptocurrency "Ethereum" became the most popular digital asset after bitcoin. The price of Ethereum increased 85 times in 2017, and more than 20 global top financial institutions and technology companies, such as JPMorgan Chase, Chicago Board of exchange, Microsoft, Intel and Accenture, established the enterprise Ethereum alliance, Butlin has become a blockchain God "V God" from a young boy
2. The great potential of Ethereum to activate blockchain
the emergence of Ethereum has activated the great potential behind blockchain. Why do you say that
the breakthrough of Ethereum is that it not only upgrades the blockchain to an operating system, so that you can develop an application chain on this basis, but also allows you to publish your own tokens in a very simple way
different from bitcoin's preset trading system operation, Ethereum is a programmable blockchain:
Ethereum allows users to create their own operations that meet their needs and have different degrees of complexity. In this sense, Ethereum is a platform. This "platform" has built a relatively complete "system", which is a bit similar to Android and apple. Application developers can develop various applications on this system
this setting makes Ethereum break through the single "monetary function" of bitcoin, and expand the application scenarios of blockchain technology to all aspects. Now, for example, we can do a lot of things through mobile app: paying fees, ordering meals, taking a taxi, shopping and so on. Similarly, developers can develop DAPP (blockchain application) on Ethereum. In the future, you can use DAPP to replace app, paying fees, ordering meals, taking a taxi, shopping and so on. Ethereum gives us these beautiful visions
Thirdly, the consensus mechanism of Ethereum is different from that of bitcoin. As we mentioned earlier, bitcoin decides its bookkeeping rights through the consensus mechanism of pow. Although the security index of pow is high, the energy consumption and cost of mining are huge, and the transaction processing speed is still very slow. Therefore, Ethereum further enriched the technology of bitcoin and proposed a new mining mechanism, namely, proof of interest (POS) The "proof of equity" proposed by Ethereum is similar to the shareholder mechanism. The more shares people have, the easier they are to obtain the bookkeeping right. It is a system of interest distribution according to the amount and time of holding money. The core logic of POS mechanism is: who holds the currency, who has the control of the network. It should be noted that in the POS mechanism, there is still computing power mining, which needs to solve a mathematical problem. However, the difficulty of the mathematical problem is related to the "age" of the coin holder. The longer the coin holder holds the coin, the easier the difficulty will be, and the greater the probability of digging the coin Fourthly, the controversial ICOEthereum is an open source system, similar to the current Android and apple systems. Developers can develop various applications on it. Most of the ICO projects are based on Ethereum. If developers want to develop blockchain applications (DAPP) on Ethereum, they need to raise certain funds through ICO as operation and maintenance costs
The concept of ICO was very popular in 2017, which was once considered as the main reason for the bull market in 2017 What's the matter with ICO? ICO (initial coin offering) is a way to raise funds for digital currency / blockchain projects. Because the token has market value, it can be converted into legal currency. In this way, it can be used as the development cost of the project. And early participants can get the initial issue of digital currency in returngenerally speaking, if a blockchain game company announces: we are going to issue money for private placement (ICO)! If you are particularly optimistic about this project, if you want to participate, you need to buy a certain number of Ethereum and call the wallet address of the blockchain game project party, which is equivalent to that you have participated in the crowdfunding (ICO) of the blockchain game project party. When the currency of this blockchain game company can be traded on the exchange, then they will pay you back according to certain rules
it seems that ICO in blockchain field is similar to IPO in stock field, isn't it? you 're right! In fact, ICO in the blockchain field is very similar to IPO in the stock field. Let's take a look at their general explanation:
IPO refers to an enterprise or company (limited company) selling its shares to the public for the first time
ICO refers to an enterprise or company (mostly blockchain start-ups) selling its token to the public for the first time
however, normally speaking, it is very difficult for an enterprise or company to go through the IPO process. It is very difficult to go through "BP seed round Angel round a round B round C round D pre IPO IPO IPO" without five to eight years. However, ICO in the field of blockchain can only be realized in three to eight months by "white paper - cornerstone investment - Private Placement -
- ICO - Stock Exchange"
This is also the reason why ICO is controversial. At present, many countries define ICO as an illegal act. It is not unreasonable to ban ICO, because at present, the state has no relevant supervision on this aspect, so it is very easy for the project party to illegally raise funds and circle money, which not only causes great losses to investors, but also disrupts the normal financial order Fifthly, the most important feature of Ethereum is the introction of "smart contract". What does smart contract mean? Smart contract is to define a set of trading rules in the form of code. In our daily life, we usually sign paper contracts, and the implementation of paper contracts needs centralized institutions, that is, the court to supervise. The "smart contract" proposed by Ethereum is to realize decentralized automatic execution through programthe account called "smart contract account" will only be executed according to the code. This technology has a wide range of applications, including insurance, equity, trust and so on. It can be said that this technology can be applied to all activities that need trust
Sixth, the significance of Ethereum: it represents the blockchain 2.0 era. After the glorious period of 2017, now, in the face of bear market, some ICO projects are worried about being tired by the bear market and cash out one after another, leading to a sharp drop in the price of Ethereum. V God, the founder of Ethereum, is also deeply involved in all kinds of rumors. There are often rumors that he is going to quit Ethereum and he is running away However, Ethereum is indeed a leap forward in blockchain technology, which represents the era of blockchain2.0. If bitcoin represents the era of blockchain 1.0, it provides new ideas and new methods for value transfer; Then, the blockchain 2.0 era represented by Ethereum makes the commercial application of blockchain possible
Almost everyone, even those who don't believe in universal certification, has a positive view on blockchain technology, because it may change the whole world. However, it has been ten years since the invention of blockchain technology, and we still do not really use blockchain technology. Some people say that bitcoin is based on blockchain technology, so with its development, the main use of blockchain is as a payment system or value storage means
there are many examples
there is no doubt that blockchain technology can be integrated into almost all sectors of modern life (including the above sectors). However, it has been nearly 10 years since the birth of blockchain technology, and no field has replaced the original technology with blockchain technology. These ideas are good, but the technology is too slow to implement
what is a blockchain? How does it work
bitcoin has become the trend of modern Internet, followed by blockchain. It is said that blockchain technology will lead to fundamental changes in Internet operation, enterprise operation and everything else
but what is blockchain? Most of us don't know much about blockchain. If you want to understand blockchain, you can read this article carefully
what is a blockchain? In the simplest terms, blockchain is a distributed ledger
to understand what this means, let's first look at its opposite: a centralized ledger. Because blockchain technology starts from finance, we will also use the bank as an example
the following is the process of our bank debit card transaction:
you can buy goods by swiping your card in the store
the merchant sends the bill to your bank to get the agreed amount
your bank will verify whether you are likely to authorize the purchase
banks remit money to businesses
finally, the bank records this information in its ledger
there are a lot of technologies involved here, but basically that's it. The last step is important - the bank keeps track of all transactions made by the customer. This ledger goes all the way back to the first transaction the bank made
the ledger is kept, maintained and supervised by the bank. You can read it in your online bank account, but you can't change it. The bank is in full control. If it decides to make a change, there's nothing you can do
it is crucial that if hackers can access the bank's ledger, it may lead to many problems. They can change the account balance to make it look like some transaction never happened, and so on
that's why distributed ledger is so cool
blockchain network visualization
if the bank operates on a distributed ledger, each member of the bank will have a of the ledger. Whenever any member of the bank makes a purchase, they will tell all other members of the bank
each member validates the transaction and adds it to the ledger (the added record is called a "block"). This has some important benefits because there are no centralized permissions to manipulate records. Hacker access to one ledger won't be a big problem because other ledgers can easily verify it
on the other hand, it requires a lot of work. In short, the second system is blockchain (at least in the financial scenario)
as mentioned above, blockchain is a decentralized transaction list. If I send Xiaoming two bitcoins, I will send a message to everyone in the network, saying "I am sending Xiaoming two bitcoins", and they will record the transaction<
bitcoin and blockchain
let's take bitcoin as an example to illustrate
bitcoin transaction
but the transaction must be verified. This is where blockchain technology has become a bit more complex. Each bitcoin wallet (which we will complete in one second) has a public and private key
you use your private key to send transaction requests to other members of the network and confirm that you have cryptocurrency in your account. If they do, they allow transactions to register on the ledger
the mechanism of public / private key system is very complex, but it comes down to that every transaction is verifiable and secure< However, the computing cost of the whole system is very high. Everyone who updates the ledger needs a lot of authority to validate transactions and modify the ledger. This is where mining comes in. People who verify and modify use their own computing resources, and each time they get a small transaction fee
and they're using a lot of electricity to do it
in this way, each transaction will be verified and added to the ledger, and the person who performs the verification and modification will be paid. This is a reasonable system
at the same time, it is also very safe. To change a single block, you have to change each subsequent block. After all this is done, validation will fail because other copies of the chain will show someone tampered with one
how to define blockchain is a difficult problem
although the mechanism behind blockchain technology is not always intuitive, it seems that it is not too difficult to explain what blockchain is. But what we're describing here is the traditional definition
we can use this special type of blockchain for a wide range of applications;, Such as cryptocurrency, sharing medical information, sending security messages and so on. But more blockchain like technologies are being developed for other uses
for example, companies may use internal blockchains to manage problem tracking in software. Each block in the chain may represent a problem, and users can publish updates to the network. But is this a blockchain? In this case, the ledger is not public, it is only visible within the company
some people will say that this is not a blockchain
other blockchain like technologies are not encrypted. Are they still blockchain? What if it's centrally managed but uses other blockchain features? What defines the lowest level of blockchain technology? There is no consensus on these issues
what is a blockchain wallet
we usually hear people talk about bitcoin wallets, Ethernet wallets and other cryptocurrency specific wallets. But wallet technology can be used in any system that uses blockchain
a wallet is the software or hardware that "saves" your cryptocurrency. But it doesn't really have anything, it's just a place to store public and private keys. This information allows you to access the currency shown in the public ledger
the wallet is the only record of the key. So if you lose it, you will no longer be able to access your cryptocurrency
in the future of blockchain, how will it change our lives
one important thing about blockchain is that it is a public resource and no one really owns it because everyone owns it
blockchain is more than science fiction. We don't need to understand the mechanism behind this technology, but you need to understand that it may completely change our lives in the next 20 years
that sounds bold, but remember, 20 years ago, we were browsing the Internet on Netscape, using the most advanced Motorola flip phone, and buying our first DVD player. At that time, if we imagined that the computer could be held in our hands, and that we could buy a car, pay for money and watch movies on it, it would be considered a fantasy
although the impact of blockchain may not be as obvious as the Internet or as tangible as mobile phones, blockchain will effectively solve many troubles in daily life. For example, intermediary entrapment, transaction delay and so on. In our present life, middlemen can be seen everywhere. We take it for granted that they are a part of our life. If one day, these intermediaries no longer exist, you will find that the world will become a different one
imagine that by 2040, blockchain may become a mature and widely used technology. One day, you can't do without blockchain, just as you can't do without the Internet now, you will be surprised that this decentralized accounting technology has become a part of your lifestyle<
first praise
+ 1
A: the basic characteristics of blockchain
I. decentralization
blockchain technology does not rely on additional third-party management institutions or hardware facilities, and there is no central control. In addition to the self-contained blockchain itself, each node realizes information self verification, transmission and management through distributed accounting and storage
the foundation of blockchain technology is open source. In addition to the private information of all parties involved in the transaction is encrypted, the data of blockchain is open to everyone. Anyone can query blockchain data and develop related applications through the open interface, so the information of the whole system is highly transparent
Third, independencebased on consensus specifications and Protocols (similar to various mathematical algorithms such as hash algorithm used by bitcoin), the whole blockchain system does not rely on other third parties, and all nodes can automatically and safely verify and exchange data in the system without any human intervention
Four, safetyas long as 51% of all data nodes cannot be controlled, the network data cannot be arbitrarily controlled and modified, which makes the blockchain itself relatively safe and avoids subjective and artificial data changes
5. Anonymityunless there are legal requirements, technically speaking, the identity information of each block node does not need to be disclosed or verified, and the information transmission can be anonymous
As we all know, blockchain is the proct of recent years, but the market for blockchain related courses can be said to be multifarious, fengmaolingjiao, each has its own merits, here, do a statistics, study, discuss and exchange together
32. What is the application of blockchain (decentralized application)
33. How to recover the stolen EOS key
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