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① How to define blockchain and what are the application scenarios of blockchain?
Many people now think that blockchain is a universal technology that can do anything. Make blockchain technology a myth!
Regarding the definition of blockchain technology, American scholar Melanie Swann defined blockchain technology as an open, transparent and decentralized technology in her book "Blockchain: A New Economic Blueprint and Introduction" database.
Definition of Blockchain: Narrow VS Broad
As for the application scenarios of blockchain technology, it is natural to combine the differences between blockchain and other technologies. In terms of system characteristics.
Blockchain technology features include:
Blockchain is a global A database storage system that can be operated collaboratively in various places is different from traditional database operations where read and write permissions are in the hands of a company or a centralized authority (a characteristic of centralization). Blockchain believes that anyone with the ability to set up a server can participate. Nuggets from all over the world have deployed their own servers locally and connected to the blockchain network to become a node in this distributed database storage system; once joined, the node enjoys exactly the same rights as all other nodes and obligations (decentralized, distributed characteristics).
At the same time, people who provide services on the blockchain can perform read and write operations on any node in the system. In the end, all nodes around the world will complete the process again and again according to a certain mechanism. Synchronize in sequence to achieve complete consistency of data in all nodes in the blockchain network.
At the beginning of this year, the term blockchain began to enter everyone’s lives. From national leaders to aunts who dance square dances, everyone knows this term. This term is widely known by Bit Brought by coins.
As we all know, the first few dozen bitcoins could only be exchanged for one pizza. At its peak, it was more than 20,000 US dollars each, which has skyrocketed by more than a thousand times, which has also benefited a large number of wealthy people. Currently, there are blockchain The virtual currency generated by technology is gradually entering into everyone's life, and many people have joined the ranks of currency speculation. I often hear people say that if you buy the right currency a hundred times, a bicycle will become a sports car, and one coin will turn a young model. You can imagine how many of them are involved. Attractive.
Since 2008, various games applying blockchain technology have also become popular, such as development games (Network Letts Dog, 360 Block Cat), mining games (NetEase Planet, Virtual Earth, Gongxinbao), these are attracting everyone to join in the name of blockchain, and of course there are some that are really reliable, which requires everyone to identify them carefully.
Blockchain is a method that connects data blocks in an orderly manner and cryptographically ensures that they cannot be tampered with, Unforgeable distributed ledger (database) technology. In layman's terms, blockchain technology can achieve openness, transparency, non-tampering, non-forgery, and traceability of all data information in the system without the need for third-party endorsement. As an underlying protocol or technical solution, blockchain can effectively solve the problem of trust and realize the free transfer of value. It has broad prospects in the fields of digital currency, financial asset transaction settlement, digital government affairs, and certificate deposit and anti-counterfeiting data services.
Digital currency
After experiencing physical objects, precious metals, banknotes and other forms, digital currency has become the development direction of the digital economy era. Compared with physical currency, digital currency has the characteristics of easy portability and storage, low circulation cost, convenient use, easy anti-counterfeiting and management, breaking geographical restrictions, and better integration.
Bitcoin technically implements an electronic cash system in which both parties to the transaction can directly transfer funds to each other without the need for third-party transfer or arbitration. In June 2019, the Internet giant Facebook also released a white paper on its cryptocurrency Libra. Whether it is Bitcoin or Libra, the underlying technology they rely on is blockchain technology.
my country began the development of central bank digital currency as early as 2014. my country's digital currency DC/EP adopts a two-tier operating system: the central bank does not directly issue digital currency to the public. Instead, the central bank redeems the digital currency to various commercial banks or other legal operating institutions, and then these institutions exchange it for public supply. its use. In early August 2019, the central bank held a video conference on work for the second half of the year. The meeting called for accelerating the pace of research and development of the national legal digital currency.
Financial asset transaction settlement
Blockchain technology naturally has financial attributes, and it is causing disruptive changes in the financial industry. In terms of payment and settlement, under the blockchain distributed ledger system, multiple market participants jointly maintain and synchronize a "general ledger" in real time. Payment, clearing, and settlement that currently take two or three days can be completed in just a few minutes. tasks, reducing the complexity and cost of cross-bank and cross-border transactions. At the same time, the underlying encryption technology of the blockchain ensures that participants cannot tamper with the ledger, ensuring that transaction records are transparent and safe. Regulators can easily track transactions on the chain and quickly locate high-risk capital flows. In terms of securities issuance transactions, traditional stock issuance has long procedures, high costs, and complex links. Blockchain technology can weaken the role of underwriting institutions and help all parties establish fast and accurate information exchange and sharing channels. Issuers handle issuance on their own through smart contracts, and regulatory authorities With unified review and verification, investors can also bypass intermediaries and conduct direct operations. In terms of digital bills and supply chain finance, blockchain technology can effectively solve the financing difficulties of small and medium-sized enterprises. It is difficult for current supply chain finance to benefit small and medium-sized enterprises in the upper reaches of the industrial chain, because they often do not have direct trade relations with core enterprises, and it is difficult for financial institutions to evaluate their credit qualifications. Based on blockchain technology, we can establish a consortium chain network covering core enterprises,Upstream and downstream suppliers, financial institutions, etc., core enterprises issue accounts receivable certificates to their suppliers. The bills can be transferred between suppliers after being digitized on the chain. Each level of supplier can use the digital bill certificate to achieve the corresponding amount of financing. .
Digital Government Affairs
Blockchain can make data run and greatly streamline the service process. The distributed technology of blockchain can allow government departments to be centralized on one chain, and all service processes are delivered to smart contracts. As long as the service personnel pass the identity authentication and electronic signature in one department, the smart contracts can be automatically processed and transferred, and the subsequent steps can be completed in sequence. All approvals and signatures. Blockchain invoice is the earliest application of domestic blockchain technology. The tax department launched the "Tax Chain" platform for blockchain electronic invoices. The tax department, the issuer, and the payee join the "Tax Chain" network through unique digital identities, truly realizing "instant invoicing for transactions" and "instant reimbursement after invoicing" - in seconds Level invoicing and minute-level reimbursement accounting significantly reduce tax collection and management costs, and effectively solve problems such as data tampering, over-reporting of one ticket, and tax evasion. Poverty alleviation is another practical application of blockchain technology. Utilize the characteristics of openness, transparency, traceability, and non-tampering of blockchain technology to achieve transparent use, precise investment, and efficient management of poverty alleviation funds.
Evidence-based anti-counterfeiting
Blockchain can prove the existence of a file or digital content at a specific time through hash timestamps, and it is open, non-tamperable, and traceable. It provides perfect solutions for judicial forensics, identity certification, property rights protection, anti-counterfeiting and traceability, etc. In the field of intellectual property, the digital signature of blockchain technology and on-chain certificates can confirm the rights of text, pictures, audio and video, etc., and create and execute transactions through smart contracts, allowing creators to regain pricing power and preserve data formation in real time. The evidence chain covers the three major scenarios of rights confirmation, transaction and rights protection. In the field of anti-counterfeiting and traceability, blockchain technology can be widely used in various fields such as food and medicine, agricultural products, alcohol, and luxury goods through supply chain tracking.
Data services
Blockchain technology will greatly optimize existing big data applications and play a huge role in data circulation and sharing. In the future, the Internet, artificial intelligence, and the Internet of Things will generate massive amounts of data. The existing centralized data storage (computing model) will face huge challenges. Edge storage (computing) based on blockchain technology is expected to become a future solution. Furthermore, the non-tampering and traceability mechanism of blockchain ensures the authenticity and high quality of data, which becomes the basis for all data applications such as big data, deep learning, and artificial intelligence. Finally, blockchain can realize multi-party collaborative data calculations while protecting data privacy, and is expected to solve the problems of "data monopoly" and "data islands" and realize the value of data circulation. In response to the current blockchain development stage, in order to meet the blockchain development and application needs of general business users, many traditional cloud service providers have begun to deploy their own BaaS ("Blockchain as a Service") solutions. The combination of blockchain and cloud computing will be effectiveReduce enterprise blockchain deployment costs and promote the implementation of blockchain application scenarios. In the future, blockchain technology will also play an important role in many fields such as charity, insurance, energy, logistics, and the Internet of Things.
The three words "blockchain" were completely ignited during the Spring Festival that just passed. The limelight overshadowed everything. Some people said that this was the arrival of a new era. The past It has become a classic, and some people say that it is all hype and is ultimately a bubble.
In fact, blockchain technology is not a new concept. It has been applied to many industries, such as electronic signatures, as early as the past two years. Recently, the third-party electronic signature platform eShanbao revealed the latest progress of blockchain applications to NewSeed.
Currently, blockchain technology is mainly used in e-signing products for certificate deposit and certificate issuance. The application scenarios include copyright protection and online signing. , web page forensics, phone recording, email storage of evidence, etc.
Take the rights protection of online works as an example. Since online rights protection generally adopts the method of collecting evidence after the fact, real-time confirmation of rights is not carried out in the process of evidence generation, so the entire confirmation process is difficult. The copyright process is time-consuming, difficult and costly to obtain evidence, and extremely difficult to prove and trace the source. It cannot meet the characteristics of rapid dissemination and large quantity of online works.
eShanbao's new intellectual property protection solution based on timestamp + blockchain starts from the user's real-name authentication and solidifies the information generated in the process in real time. Electronic data, and through the time source service synchronized with the National Time Service Center, online works are stamped with legally valid timestamps to prove that electronic files have not been tampered with in a certain period of time. Blockchain technology can establish point-to-point trust in the network, ensuring that all blockchain nodes can record complete copyright confirmation and transaction records, and can trace their origins, truly realizing anti-repudiation and anti-tampering, and realizing a kind of distribution. trust infrastructure.
Founder and CEO Jin Hongzhou believes that the application of decentralized blockchain technology has greatly improved the efficiency of data storage and certification, and The credibility of the identity of the parties reduces the cost of trust, but it cannot replace the original centralized public key encryption technology. The two should complement each other. Through the combination of the two, it can provide users with real-time and reliable Confirmation plan.
Next, e-Shanbao will also focus on building a smart contract platform based on blockchain technology. Jin Hongzhou said that data storage, Issuing certificates is only a relatively superficial application based on blockchain technology. It is the first step to implement blockchain technology, and the realization of real smart contracts is the second step. “Smart contracts cannot simply be understood as electronicContract refers to a process, from conclusion of contract to confirmation to final execution. "Jin Hongzhou explained.
From a technical perspective, blockchain is not a brand-new technology, but an integration of distributed data storage, point-to-point transmission, consensus mechanism, encryption algorithm, smart contract and other computer technologies. New application model. Specifically, blockchain technology is a technical solution that collectively maintains a reliable database in a decentralized, high-trust manner.
Due to the characteristics of "decentralization" and "distribution" With advantages such as "automatic data storage", "traceability", "tamper resistance", and "openness and transparency", blockchain technology can effectively solve the problems of data authenticity, security and openness in the data field. A data management environment to prevent and avoid various data management problems such as data fraud, tampering, and loss, and promote efficient sharing and application of data. In the process of practical exploration, the application scope of blockchain technology continues to expand, especially in the field of public resource transactions. Empower public resource transaction management services.
Promote transaction data sharing and transaction witness
Promote transaction data sharing
Currently, the data of different trading centers are not interoperable, and the subject information of different trading centers needs to be entered repeatedly. During the bid evaluation process, it is difficult to verify the off-site performance provided by the bidders, and the same personnel are duplicated. Problems such as difficulty in troubleshooting as a project manager and low cost of breach of trust by transaction entities. Establishing a cross-regional entity database based on blockchain can well alleviate the above problems.
The distributed ledger features based on blockchain can Effectively guaranteeing the real-time or quasi-real-time sharing of data, it can reduce repeated entry operations of subject information; the use of blockchain information that cannot be tampered with can ensure the authenticity of the data flow process on the chain. The performance of bidders in the regional alliance is directly taken from the data on the chain. This makes it impossible to hide false performance. At the same time, the sharing of bidding behavior data through the blockchain provides a data basis for the development of "joint punishment of dishonest enterprises".
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Blockchain-based transaction witness
The document "Guiding Opinions on Deepening the Integration and Sharing of Public Resource Trading Platforms" (State Office Letter [2019] No. 41) points out the need to optimize witness, venue, Information, archives, expert extraction and other services. However, at present, public resource transaction process witnessing is mainly based on manual on-site witnessing, which has limited witnessing strength, high occupation of human resources, and limited witnessing effect. Due to its centralized characteristics, the traditional digital witnessing system is easy to collect data afterwards Be tampered with, and the data is easily damaged or lost during the storage and migration process, which has certain flaws in terms of security and usability.
Utilize the distributed, difficult to tamper, and traceable characteristics of the blockchain to verify each transaction The data generated in the link are solidified and stored as evidence, using timestamp technology and summary algorithms., Electronic signature technology accurately records the time, content and data source of data generation. According to the technical characteristics of the blockchain, simple structured data can be directly saved on the blockchain. For unstructured layout files, videos, audio and other large files, the summary information and original files can be saved through the blockchain. Save via a distributed file storage service. When there are disputes or problems in a transaction, the blockchain can provide a set of credible transaction process data and clarify the responsibilities of all parties involved in the transaction. Achieve the goals of risk prevention and control in all aspects, traceability of the entire process, and improvement of all-round services.
Promote the rationalization of electronic guarantee rates
Promote financial services and corporate financing for bidding companies
Promote the rationalization of electronic guarantee rates
At present, electronic bidding deposit guarantee letters have certain applications in the field of bidding, solving the problem of bidding deposit funds for bidding companies. Occupancy issues. However, because financial institutions currently do not have reliable historical bidding behavior data of bidders, they are unable to judge the default risks of different bidders. As a result, the guarantee services charged to bidders adopt fixed rates, which makes a small number of bids with high default risks The cost of personal guarantee is allocated to most bidders with low default risk, which increases the guarantee rates for most bidders to a certain extent.
At present, it is up to the bidder to choose whether to use an electronic letter of guarantee, and the rate is the main choice basis for the bidder. If the bidder performance records are shared through the blockchain and the performance risks of different bidders are analyzed, it will be Different bidders provide different guarantee rates, which not only reduces the risks of financial institutions, but also reduces the use costs of most bidders and promotes the use of bid guarantees. To a certain extent, it can also encourage bidders to abide by their promises and maintain the order of the bidding market. .
Promote financial services for bidding companies
The bidding behavior of bidders is scattered in various trading centers, and the data is simply aggregated In a centralized information system, there is a risk of data tampering (untrustworthy), and valuable bidder transaction behavior data cannot be gathered and shared safely and reliably. Through blockchain technology, bidders from multiple trading centers are gathered, and historical bidding, winning bids, defaults, violations and other behavioral records provide data support for financial institutions to evaluate the bidders' credit in the bidding sub-sector.
Solving the financing problems of successful bidders
Traditional corporate loans mainly evaluate the company's solvency: collateral, audit There are requirements for accurate financial statements and sustainable profitability, but most small and medium-sized enterprises cannot provide these "proofs" at all. Difficulty and expensive financing have become the challenges faced by many small and medium-sized enterprises in bidding activities.The problem. Using the methods of the past will no longer work. To solve the financing difficulties of small and medium-sized enterprises, we can only rely on new technologies and new tools. With the help of the non-tamperable characteristics of blockchain, primary business data from multiple trading centers are gathered, and big data analysis technology is combined to build a portrait of a credible bidder. On the one hand, it improves the risk control level of financial institutions and taps high-quality bidding companies. On the other hand, it lowers the loan threshold for bidding companies and optimizes the service experience.
Drawing on the supply chain finance model, the bidder is a core enterprise with good credit in government departments, national enterprises and institutions, and the winning contract obtained by the winning bidder as a supplier is considered by financial institutions to be a high-quality asset. Apply for a loan from a financial institution. Under the traditional paper-based model, there is a risk of order and contract fraud and the process is cumbersome. Centralized information systems require operators to have strong authority. The distributed ledger and difficult-to-tamper characteristics of the blockchain will help solve the above problems. The contract signing between the tenderer and the bidder and the subsequent financial service links will be realized on the blockchain, which not only solves the problem of data trustworthiness but also reduces the risk of corruption. The entire system relies on a centralized authority.
Through further analysis, we found that credit sales are currently prevalent among domestic enterprises, and the upstream suppliers of the winning bidder have a large funding gap. The credit of the bidder can only be passed to the winning bidder (the winning contract cannot be split or transferred), and the upstream suppliers Business owners are unable to obtain high-quality loans from financial institutions. If the winning contract is converted into a "pass" on the chain, the "pass" can be split, and the winning bidder holding the "pass" can pay part or all of the voucher to the upstream supplier, making it discountable and financing. The "tokens" on the chain can be split and transferred from first-level suppliers to second-level (and multi-level) suppliers, thereby allowing core enterprise credit to be transferred to multi-level suppliers. The shortage of funds from suppliers due to credit sales has been solved, improving the business environment; through value transfer through the blockchain, the financing cycle has been greatly shortened; the cost of supplier loans has been reduced, which will help reduce the production costs of raw materials or intermediate products, and ultimately Increase bidders' profit margins and indirectly reduce bidders' costs.
Regarding blockchain, we can imagine a decentralized management model and technical processing method.
Let me give you an example. There are five people in your family, and they have never been able to figure out how to arrange work and handle family relationships.
So, you and your family discuss it together and simply use voting to solve the problem.
Then this way of voting to solve problems can be called the most elementary blockchain.
Decentralization solves problems.
What application scenarios can blockchain have?
In fact, many of our families and many organizations use blockchain management forms every day
However, this kind of blockchain application for organizational relationships cannot produce Economic Value.
What economic benefits can blockchain have?What about applications?
The first type is used for tax deposit certificates, bank transfers, etc.
Make full use of the traceability function of the blockchain so that all records can be retrieved and queried at any time
The second type is applied to enterprise operation and management
Enterprises using blockchain management can better solve the problems of enterprise development and allow enterprises to Able to develop faster and make more money.
Summary: The application scenarios of blockchain include taxation, bank transfers, etc., and can also be applied to business operations.
The characteristics of blockchain are distributed accounting and decentralization, but the ultimate goal is to make people get along more equally. Technology is meaningful only when it serves human values, and technology that meets human value needs will develop. Therefore, blockchain is in line with human pursuit of freedom and equality, so its trend to become mainstream is unstoppable.
Currently, there are many blockchain gimmicks, which are basically used to issue coins. The newly launched ono is a decentralized, free and global social platform. Due to decentralization, your chat communication information is peer-to-peer and cannot be viewed by others. In other words, your every word and deed will no longer be recorded and reviewed at any time like it is now on WeChat, QQ, and Facebook, freeing you from the trouble of surveillance.
In fact, blockchain technology can be used in any field. Information that previously required third-party confirmation can be completed online and confirmed at multiple nodes, making it difficult (almost impossible) to delete.
At present, blockchain is still in its infancy, and the technology is not mature enough, but it is also a better time to enter.
Blockchain is a decentralized technology. Blockchain can be applied to all products currently covered by the Internet.
The most popular application industry at present is the financial industry.
An application that has been implemented is product traceability. Alibaba and JD.com are already using blockchain technology to fully trace the origin of some of the products they sell. Consumers can trace the origin of the purchased products. There are also many blockchain applications in the digital advertising industry. Since traffic fraud in digital advertising causes losses of tens of billions of dollars every year, there are already blockchain application projects based on digital advertising, such as DCAD, which is based on blockchain. The digital advertising application of blockchain technology mainly solves the problem of traffic fraud
In the future, as the application of blockchain technology becomes more mature, it will be applied in many industries, creating a new ecosystem based on technological trust. Mode
What is blockchain If you explain blockchain in non-technical terms, blockchain is a place where data is stored. However, the data stored in the blockchain is safe and reliable and does not need to be managed by anyone. So in the Internet, a place where data is exploding and information is exploding, how can there be such aThe place will be like a magical treasure land.
If you ask what the blockchain can do, it is better to say what applications require the use of the blockchain. As mentioned earlier, blockchain is a safe place, so wherever data needs to be protected securely on the Internet, blockchain technology needs to be used. For example:
Because the use of blockchain technology can better protect the data of policyholders, in today’s Internet, data is value and wealth, so value protection and value transmission are the future development directions of the Internet. And blockchain technology can really do just that.
If there are any deficiencies, you are welcome to comment and correct me.
In a narrow sense, blockchain is a chained data structure that combines data blocks in a sequential manner in chronological order, and is cryptographically guaranteed to be non-tamperable and non-tamperable. Fake distributed ledger.
The two parties involved in the transaction do not need to know who the other party is, nor do they need a third party for trust endorsement. They only need to trust a common algorithm to establish mutual trust and conduct direct transactions.
Its characteristics are trustlessness and decentralization. The destruction of each node's ledger has no impact on the entire blockchain. The blockchain runs point-to-point payments without a center that may cheat, and the security is greatly improved. Improved, the entire transaction network has changed from a star structure to a point-to-point P2P structure.
In the future, blockchain will be used in many fields and will have a great impact on human life. . It can be widely used in fields ranging from digital currency to securities and financial contracts, medical care, games, artificial intelligence, smart contracts, Internet of Things, e-commerce, file storage and other fields.
1. Cloud storage
This is the statistics of current cloud storage on the Internet. In terms of volume, Google has the largest volume, which is 8,000PB. So what if we share the idle data on the Internet?
Starlight Cloud builds a blockchain data computing and storage lake through Starlight Chain, with a total storage capacity of 15,000P (approximately 15.72864 billion G) in the future. This will be more than 10 times that of Alibaba Cloud's 1500PB! It is also more than four times the size of the Taizhou Storage Center, the largest storage lake in the world after expansion.
2. Medical aspects
Using blockchain technology to save personal medical records also retains personal medical historical data, which can be used when seeing a doctor or planning for your own health in the future. Historical data can be called directly. These data are highly private, and the use of blockchain technology also helps protect patient privacy.
② What exactly is blockchain
Let’s talk about some basic concepts first.
Network says blockchain is distributedA new usage model of computer technology such as data storage, point-to-point transmission, consensus mechanism, encryption algorithm, etc. It is essentially a decentralized database, and as the underlying technology of Bitcoin, it is a series of data blocks generated by cryptography.
We try to translate "what is blockchain" into "human language".
The definition refers to the "decentralized database" nature of blockchain3354. This is very different from the traditional "centralized database" in storage, update and operation.
A centralized database can be thought of as having this shape:
For example, if I want to use Alipay to pay a Taobao seller, all data requests from when I make money to when he receives the money will be centrally processed by Alipay. The advantage of this data structure is that as long as Alipay is responsible for the efficient and safe operation of the system, others can unconditionally believe it without worrying; the disadvantage is that if there is a problem with Alipay, such as being hacked, the server being burned, a traitor appearing, and the company running away (Of course, the possibility of the above is extremely low), the balance details and other information in our Alipay will be confused.
Then some people think that this kind of low-probability event can use any technical means to avoid individual risks, and not only hand over the data to a centralized organization. For example, everyone can store and process data.
The database structure may look like this:
This picture is a schematic structural diagram of a "distributed database". Each point is a server, they all have equal rights to record and calculate data, and information is spread point-to-point. At first glance, it seems that it can indeed resist the risk caused by the crash of a certain node, but it is also very confusing and inefficient intuitively. Who will handle my information, and who has the final say on the outcome?
At this time, the "consensus mechanism" in the definition of blockchain comes into play. The consensus mechanism mainly "stipulates" the following things: who will process a data request (what qualifications are required); who will verify the results (to see if he has handled it well); how to prevent processors and verifiers from colluding with each other, etc.
Some people may like to be questioned when a "rule" is made. In order to form a stronger consensus, in addition to making the rules more reasonable, they must also be more attractive so that people are interested and motivated to participate in data processing. This involves the incentive mechanism of the public chain. We will start again later when we discuss the classification of blockchain and the role of digital currencies.
When we hand over a transaction to a distributed network, there is also a "psychological threshold": there are so many nodes that can process information, and I don't know any of them (unlike Alipay, if it hurts me, I can go and file a lawsuit against it). They all have my data, why should I trust them?
At this time, encryption algorithm (the last descriptive word in the definition of blockchain) comes on stage.
In the blockchain network, the data requests we send will be encrypted according to cryptographic principles into a string of characters that the recipient cannot understand at all. Behind this encryption method is the support of a hash algorithm.
Hash algorithms can quickly convert any type of data into hash values. This change is one-way irreversible, deterministic, random, and anti-collision. becauseWith these features, the person handling my data request can record the information for me, but they have no idea who I am or what I do.
So far, the working principle of the decentralized network has been introduced. But we seem to have overlooked one detail. The previous diagram is a net. Where are the pulleys and chains? Why do we call it blockchain?
To understand this matter, we need to clarify a few knowledge points first:
The previous picture is actually a "macro" database perspective, showing the basic rules and processes of the blockchain system for processing information. . And specifically at the "micro" data log level, we will find that the ledger is packaged, compressed, stored in blocks, and strung together in chronological order to form a "chain structure", like this:
Figure Each ring in can be regarded as a building block, and many links are linked together to form a blockchain. Blocks store data, unlike ordinary data storage: on a blockchain, the data in a later block contains the data in the previous block.
In order to academically explain the fields of each part of the data in the block, we tried to use a book metaphor to describe what a blockchain data structure is.
Usually, when we read a book, we read the first page, then the second and third pages. The spine is a physical existence that fixes the order of each page. Even if the book is scattered, the order of each numbered page can be determined.
Inside the blockchain, each block is labeled with a page number, the second page contains the first page's content, the third page's content contains the first and second page's content. The tenth page contains the previous Nine pages of content.
It is such a nested chain that can be traced back to the original data.
This brings up an important attribute of blockchain: traceability.
When the data in the blockchain needs to be updated, that is when new blocks are generated in sequence, the "consensus algorithm" comes into play again. This algorithm stipulates that a new block can only be formed if it is recognized by more than 51% of the nodes in the entire network. To put it bluntly, it is a matter of voting, and it can be elected if more than half of the people agree. This makes the data on the blockchain difficult to tamper with. If I were to force a change, there would be too many people to bribe and the cost would be too high to be worth it.
This is what people often call the "non-tamperable" feature of blockchain.
Another reason why blockchain gives people a sense of trust is because of "smart contracts."
Smart contracts are commitment agreements defined and automatically executed by computer programs. It is a set of transaction rules executed by code, similar to the current automatic repayment function of credit cards. If you turn on this function, you don’t have to worry about anything. The bank will automatically deduct the money you owe when it is due.
When your friend borrows money from you but doesn't remember to pay it back, or makes excuses not to pay it back, smart contracts can prevent breach of contract. Once the terms in the contract are triggered, such as when it is time to repay the money, or there is a limit in his account, the code will automatically execute, and the money he owes you will be automatically transferred back whether he wants it or not.
Let’s briefly summarize. Blockchain technology is mainly decentralized, difficult to tamper with, and traceable, which represents more security and trustlessness. But it also brings new problems: redundancy andIt is inefficient and requires many nodes to agree with the rules and actively participate.
This concludes the "drying" section. Next, let’s talk about unofficial history and the official history of blockchain.
A new technology is often used to serve a certain task.
Or goals. So where was blockchain first used, and who came up with it first?
Let's go back to 2008.
On September 21, Wall Street investment banks collapsed one after another, and the Federal Reserve announced that it would convert the only two remaining investment banks (Goldman Sachs Group and Morgan Stanley) into commercial banks; it hoped to survive the financial crisis by absorbing savings. On October 3, the Bush administration signed a $700 billion financial rescue package.
Twenty-eight days later, on November 1, 2008, a new post appeared in a cryptography mailing group: "I am developing a new electronic currency system that is completely peer-to-peer and does not require a third party. Three-party trust institution." The text of the post is a paper titled "Bitcoin: A Peer-to-Peer Electronic Cash System", signed by Satoshi Nakamoto.
The paper explains the design of this peer-to-peer electronic cash system with a more rigorous logic. It first discusses the problem that financial institutions are subject to "trust based" (based on credit), and then explains step by step how to achieve "no third-party agency" , and cleverly solved the technical problems left by the predecessors.
Two months later, Satoshi Nakamoto released the first version of the open source Bitcoin client and mined 50 Bitcoins for the first time. The block that generated the first batch of Bitcoins is called the "Genesis block". The genesis block was compiled into block 0 and was not uploaded to the chain. It took Satoshi Nakamoto 6 days to mine this block. This also sparked discussion in the bitcointalk forum. Bitcoin "believers" thought of the Bible, "God created the heavens and the earth in six days, and then rested on the seventh day."
Although concepts such as decentralized, token, and economy did not appear in the paper, Satoshi Nakamoto explained in detail the role of blocks and chains in the network. working principle. So, there is Block Chain.
This paper later became the "Bible" of the "Bit Cult", technology became the cornerstone of faith, and developer documentation became the "Code of Hammurabi".
After that, Bitcoin realized the first real-life payment by exchanging pizza, WikiLeaks, whose account was blocked by the US government, miraculously survived by relying on Bitcoin, Satoshi Nakamoto's "decentralization" and retirement, and the appearance of the real and the fake A series of legends such as and refutation of rumors, combined with the expectations, imagination and speculation of later generations, became "Bible stories".
There are also people who are not satisfied with the world described in the "Old Testament" and start new sects, write the doctrines into white papers, and tell the story of their faith in the ten years after Bitcoin. like 66The writing of the Bible spanned 1,500 years, and after 2,000 years of interpretation, Christianity has divided into 33,000 branches.
CoinMarketCap shows that there are more than 4,900 types of digital currencies, and the overall digital currency market size is nearly 140 million yuan. Bitcoin still leads the entire digital currency market with a market share of 66%, and the recent price has been hovering around US$7,200 per coin.
So many currencies have different functions and are divided into different categories: digital currencies represented by Bitcoin are positioned as "digital gold" and have certain value storage and hedging characteristics; Ethereum The digital currency represented by Bitcoin has become the "operational fuel" in its network system; the stable currency represented by USDT and Libra has good payment properties due to its low volatility; the digital currency issued by the central bank represented by DCEP will definitely To a certain extent, it replaces M0, allowing commercial institutions and ordinary people to receive and pay without delay when they are out of cash and disconnected from the Internet.
It can be seen that after 10 years of development of blockchain technology, the first and largest application is digital currency.
Digital currency has also become an attractive reward for participants to maintain the public chain.
So besides digital currency, where else can blockchain technology be used?
Let us recall what the essence of blockchain is—a decentralized database, and its corresponding characteristics: traceability, publicity, anonymity, and tamper-proofing. In theory, you can try to use blockchain to transform traditional scenarios that use centralized databases to see if they are suitable.
Next, let’s talk about several industries and scenarios where blockchain has been successfully implemented:
Blockchain can prove the existence of a certain file or digital content at a specific time through hash timestamps, providing judicial authentication, Identity proof, property rights protection, anti-counterfeiting traceability, etc. provide perfect solutions
In the field of anti-counterfeiting traceability, blockchain technology can be widely used in various fields such as food and medicine, agricultural products, alcohol, and luxury goods through supply chain tracking.
Give two examples.
Blockchain can allow government data to be run, greatly streamlining service processes
The distributed technology of blockchain can allow government departments to be centralized on one chain, and all service processes are delivered to smart contracts, and the workers only need to be in one department Through identity authentication and electronic signature, smart contracts can be automatically processed and transferred, and all subsequent approvals and signatures can be completed in sequence.
Blockchain invoices are the earliest use of blockchain technology in China. The tax department launched the "Tax Chain" platform for blockchain electronic invoices. The tax department, the issuer, and the payee join the "Tax Chain" network through unique digital identities, truly realizing "instant invoicing for transactions" and "instant reimbursement after invoicing" - in seconds Level invoicing and minute-level reimbursement accounting significantly reduce tax collection and management costs, and effectively solve problems such as data tampering, over-reporting of one ticket, and tax evasion.
Poverty alleviation is another practical application of blockchain technology. Utilize the characteristics of openness, transparency, traceability, and non-tampering of blockchain technology to achieve transparent use, precise investment, and efficient management of poverty alleviation funds.
Give two examples as well.
By the policeThe eID network identity operation agency guided by the Ministry of Education's Third Research Institute is jointly developing a "digital identity chain" with Gongyilian, which is based on the citizen's identity number and is issued to Chinese citizens based on cryptographic algorithms. Since it was put into operation, the eID digital identity system has served the full life cycle management of 100 million eIDs, effectively alleviating the problems of personal identity information being fraudulently used, abused and privacy leaked.
Odaily Planet Daily compiled 5 identity chain projects registered with the Cyberspace Administration of China
Blockchain technology naturally has financial attributes
In terms of payment and settlement, under the blockchain distributed ledger system, there are many markets Participants jointly maintain and synchronize a "general ledger" in real time. In just a few minutes, they can complete payment, clearing, and settlement tasks that currently take two or three days to complete, reducing the complexity and cost of cross-bank and cross-border transactions. At the same time, the underlying encryption technology of the blockchain ensures that participants cannot tamper with the ledger, ensuring that transaction records are transparent and safe. Regulators can easily track transactions on the chain and quickly locate high-risk capital flows.
In terms of securities issuance transactions, the traditional stock issuance process is long, costly and complicated. Blockchain technology can weaken the role of underwriting institutions and help all parties establish a fast and accurate information exchange and sharing channel. The issuer can handle the issuance on its own through smart contracts. , regulatory authorities conduct unified review and verification, and investors can also bypass intermediaries for direct operations.
In terms of digital bills and supply chain finance, blockchain technology can effectively solve the financing difficulties of small and medium-sized enterprises. It is difficult for current supply chain finance to benefit small and medium-sized enterprises in the upper reaches of the industrial chain, because they often do not have direct trade relations with core enterprises, and it is difficult for financial institutions to evaluate their credit qualifications. Based on blockchain technology, we can establish a consortium chain network covering core enterprises, upstream and downstream suppliers, financial institutions, etc. The core enterprises issue accounts receivable vouchers to their suppliers. After the bills are digitized and uploaded to the chain, they can be uploaded to the supplier Transfer between them, each level of supplier can realize the corresponding amount of financing with the digital bill certificate.
Give me an example.
The China Enterprise Cloud Chain, jointly launched by ICBC, Postal Savings Bank of China, 11 central enterprises, etc., has covered 48,000 companies since its establishment in 2017, with the amount of rights confirmed on the chain reaching 100 billion yuan, and factoring financing of 57 billion yuan. , cumulative transactions reached 300 billion yuan. After receiving the loan application, financial institutions can verify the authenticity of the contract on the chain and whether the contract has been verified multiple times (multiple loans); the smart contract automatically clears and settles, reducing costs and increasing efficiency; at the same time, the accounts payable of core enterprises can have The corresponding vouchers will be split by the first-level suppliers and handed over to the second- and third-level suppliers in the chain to help them with financing; core enterprises can also use this to understand whether the entire chain is operating normally and avoid emergencies. Redemption pressure.
Blockchain technology will greatly optimize the existing use of big data and play a huge role in data circulation and sharing
The aforementioned areas are areas that we are relatively familiar with. As more new technologies develop, blockchain may be able to be combined with them and play a role in unexpected cross-fields and new scenarios that are currently unforeseen.
Future Internet, Artificial Intelligence, Internet of ThingsAll will generate massive amounts of data, and the existing centralized data storage (computing model) will face huge challenges. Edge storage (computing) based on blockchain technology is expected to become a future solution. Furthermore, the non-tampering and traceability mechanism of blockchain ensures the authenticity and high quality of data, which becomes the basis for the use of all data such as big data, deep learning, and artificial intelligence.
Finally, blockchain can realize multi-party collaborative data calculations while protecting data privacy, and is expected to solve the problems of "data monopoly" and "data islands" and realize the value of data circulation.
In response to the current blockchain development stage, in order to meet the blockchain development and use needs of general business users, many traditional cloud service providers have begun to deploy their own BaaS ("Blockchain as a Service") solutions. The combination of blockchain and cloud computing will effectively reduce enterprise blockchain deployment costs and promote the implementation of blockchain usage scenarios. In the future, blockchain technology will also play an important role in many fields such as charity, insurance, energy, logistics, and the Internet of Things.
During this trial process from traditional technology to blockchain, we found that when certain scenarios have stronger demands for traceability, tamper-proofing, and decentralization, they also have problems with the weaknesses of blockchain (such as performance). , the requirements are not high, and this field is quite suitable for combining blockchain.
At the same time, in the process of blockchain evolution, it has also developed from a highly decentralized public chain accessible to everyone to a consortium chain with different permissions and maintained by multiple centers. Balances the advantages and disadvantages of the two systems.
Typical examples of alliance chains include: FISCO BCOS jointly developed by WeBank and the Golden Alliance Open Source Working Group, Fabric, a major contribution from IBM, and Ant Alliance Chain led by Ant Blockchain, etc.
These trustless systems represent more secure data authentication and storage mechanisms, where data is effectively authenticated and protected. Businesses or individuals can exchange or enter into contracts digitally, where these contracts are embedded in code and stored in transparent, shared databases where they cannot be deleted, tampered with, or revised.
It is boldly predicted that in the future, contracts, audits, tasks, and payments will all be digitized with unique and secure signatures. Digital signatures will be permanently identified, authenticated, legalized, and stored, and cannot be tampered with. There is no need for an intermediary to guarantee each of your transactions. You can conduct transactions without knowing the basic information of the other party. While improving information security, it effectively reduces transaction costs and improves transaction efficiency.
Generally speaking, there has been a lot of progress in the implementation of blockchain compared to two years ago.
Many improvements are at the bottom of the system, and users cannot directly see that blockchain is used, but they have actually benefited from it; some applications are still in pilot mode, and users have not yet been able to experience it. In the future, blockchain is expected to be used on a large scale and become one of the Internet infrastructure.
I hope that after reading this, you have a general understanding of what blockchain is and what blockchain can do.
Related Q&A: What is blockchain
Blockchain is actually related toIt is equivalent to a disintermediation database, which is composed of a series of data blocks. Each of its data blocks contains information about a Bitcoin network transaction, which is used to verify the validity of the information and generate the next block.
In a narrow sense, blockchain is a chain data structure that combines data blocks in a sequential manner in chronological order, and is cryptographically guaranteed to be non-tamperable and non-forgeable. distributed ledger.
In a broad sense, blockchain is actually a distributed infrastructure and computing method, which is used to ensure the security of data transmission and access.
Blockchain infrastructure:
Blockchain is composed of six infrastructures: data layer, network layer, consensus layer, incentive layer, contract layer and usage layer.
③ How do programmers view the Libra source code? There are more doubts than affirmations on GitHub
Odaily Planet Daily Translator | Moni
It has been two years since Facebook released the cryptocurrency Libra white paper Zhou, as an open source project, the source code of Libra was also released on Github, a well-known open source community and code hosting library. Although the code has not been released for a long time, given the influence of social networking giant Facebook, it has attracted the attention of a large number of commentators and programmers in the crypto community.
The Libra cryptocurrency is currently governed by the "Libra Association" and is an independent organization spun off from Facebook. As of now, the Libra project on Github has been "saved" or "starred" by nearly 10,000 users, which also represents the great interest in this project from early open source participants. In addition, more than 1,000 Libra code clone libraries have been created on Github so far, allowing programmers and "quasi-programmers" to sit down and study Libra's code carefully.
In fact, some programmers who have used Libra code have found that it "borrows" many functions from other cryptocurrency (such as Bitcoin) systems, such as opening the network for block validators Visit etc. More importantly, programmers discovered from the Libra source code that this cryptocurrency project does not seem to be as "serious" as people thought.
Mikko Ohtamaa, who created a clone project called "Libra Classic", said Facebook's release of the Libra source code on Github may be just a "bait" just to see how the community reacts.
Albert Cast, chief product officer of cryptocurrency startup Radix DLTellana commented:
In order to support this latest global financial payment system, the Libra cryptocurrency will have a team of 28 founding members responsible for verifying transactions and adding new blocks when it is issued - at least This is how it was designed at the beginning. Of course, Facebook also expressed the hope that as time goes by and the Libra network continues to expand, it will become more "decentralized" in the future.
However, the crypto community does not buy Facebook’s rhetoric.
In contrast, the original Bitcoin network was also designed as a global financial payment system, but it allowed any individual with computing resources to participate in creating and broadcasting transaction blocks, and Being able to earn block rewards, which are Bitcoins, in the process.
Because of this, some opinion leaders in the cryptocurrency industry directly criticized the authorization structure of the Libra blockchain. In addition to social media, they also dug into every aspect of the Libra code on Github. details.
On GitHub, any user with read access to the code repository can create issues and pull requests. (Planet Jun o-daily Note: A pull request is to request others to pull their own code library. If a programmer finds a problem with a certain code, he can git clone the original library on his own machine, switch to fork (fork), and modify the code Make some modifications. After completion, you can initiate a Compare & pull request, add some comments and confirm the submission. If the original library author sees your update and confirms it is correct, he will integrate your code into his own project. If the original library author The author thinks your update is problematic and can reject the code update.)
In the past four days, the Libra code base has flagged approximately 160 issues, of which more than 100 have been Authenticated repository users were closed, some of which were also marked as "off-topic." While only half of these issues were pull requests, they reinforced a widespread sentiment in the cryptocurrency community that Facebook Libra’s permissioned blockchain protocol is inherently flawed.
Github user "gazhayes" made a pull request on Tuesday (June 25). He explained:
However, the pull request of "gazhayes" has been It was closed by the official administrator of Libra GitHub on Wednesday (June 26)., which resulted in complaints and dissatisfaction from members of the programmer community, because they all believed that the pull request submitted by "gazhayes" was a legitimate comment.
Decentralized application developer Marcus Newton commented:
Calibra, which is working on building a wallet application for the Libra blockchain, responded to the "protest" of the programmer community. Ben Maurer, the company's technical director, explained:
"Libra Classic" project founder Mikko Ohtamaa seemed to agree with Ben Maurer's statement, and also pointed out that it remains to be seen whether GitHub's open source collaboration on the Libra project will be effective. Observation, he said:
However, Mikko Ohtamaa believes that as time goes by and the code is further standardized, more programmers can fully understand how the Libra network works, and the hatred of Facebook will also be reduced Certain relief, he added:
But even so, if from many perspectives there still seem to be some unresolved issues that will also affect Facebook's ambitious cryptocurrency project. Jameson Lopp, chief technology officer of encryption security startup Casa, said that there is still a lot of information about the Libra development language Move that has not been made public. He further explained:
Regarding the various doubts about the next step of the Libra open source project, Facebook Communications Manager Alexandru Voica said:
Outlier Ventures chief technology officer and co-founder Aron van Ammers believes that Facebook’s cryptocurrency project is actually still in its early stages and may not be available to people for several months. See something inspiring in it. Aron van Ammers finally concluded:
④ Is the libra code used for mining?
No.
According to the query of relevant public information, Libra is a stable currency and cannot be mined. However, its test network provides a "faucet" service, which means that it is relatively easy to obtain test coins for experience.
Libra is a blockchain project launched by Facebook. Its mission is to build a simple, borderless currency and financial infrastructure that serves billions of people.
⑤ What is libra
Libra is an encrypted digital currency initiated by Facebook. The public canThink of Libra as a payment tool like tokens and chips, but these tokens and chips are accepted all over the world. Compared with Bitcoin, Libra has the following characteristics:
(1) It also uses blockchain technology. Blockchain technology is to disperse the originally centralized transaction account books to all nodes on the transaction network, and prevent anyone from tampering with the account books by checking the account books with each other between the nodes. Libra also uses this method to save transaction records, and the security is still very high.
(2) The monetary value is different. The monetary value of Bitcoin is determined by the approval of users, so there is a problem of unstable value fluctuations. The value of Libra is tied to real currency. In order to avoid the risk of fluctuations in a single currency, Libra is anchored to the average price of a basket of currencies consisting of the US dollar, British pound, Euro and Swiss franc.
(3) Currency issuance is different. The issuance of Bitcoin is carried out by a public algorithm. As long as you run this algorithm and solve the answer, anyone can issue Bitcoin. The issuance of Libra is managed by Facebook and its partners. If you want to obtain Libra, you need to use real currency to exchange it with Facebook and its partners. From this point of view, Libra is more like a payment tool similar to tokens and chips.
