用得最多的区块链数据库是,用得最多的区块链数据库是什么

用得最多的区块链数据库是什么？目前，最受欢迎的区块链数据库是比特币，以太坊，Hyperledger Fabric和Corda。下面我们将着重介绍这四种区块链数据库的关键特性。

比特币是一种去中心化的数字货币，是目前最受欢迎的区块链数据库之一。比特币的数据库是一个分布式的公共账本，可以提供安全可靠的货币交易服务。它使用密码学技术和经济激励机制来确保网络的安全性和可靠性。它的安全性和可靠性使其成为目前最受欢迎的区块链数据库之一。

以太坊是一种去中心化的开放式计算平台，它可以用于构建和部署去中心化的应用程序。它使用一种称为智能合约的技术，可以在网络上实现安全可靠的交易。以太坊的数据库也是一个分布式的公共账本，可以提供安全可靠的交易服务。它使用智能合约技术和经济激励机制来确保网络的安全性和可靠性。

Hyperledger Fabric是一种基于区块链技术的分布式账本，可以用于构建和部署分布式应用程序。它使用一种称为智能合约的技术，可以在网络上实现安全可靠的交易。Hyperledger Fabric的数据库也是一个分布式的公共账本，可以提供安全可靠的交易服务。它使用智能合约技术和经济激励机制来确保网络的安全性和可靠性。

Corda是一种去中心化的分布式账本技术，它可以用于构建和部署去中心化的应用程序。它使用一种称为智能合约的技术，可以在网络上实现安全可靠的交易。Corda的数据库也是一个分布式的公共账本，可以提供安全可靠的交易服务。它使用智能合约技术和经济激励机制来确保网络的安全性和可靠性。

总之，比特币、以太坊、Hyperledger Fabric和Corda是目前最受欢迎的区块链数据库，它们都使用密码学技术和经济激励机制来确保网络的安全性和可靠性。它们都可以提供安全可靠的交易服务，为用户提供更多的安全保障。

① What kind of database is blockchain technology?

Blockchain is a shared distributed database technology. Although the one-sentence introduction to blockchain is worded differently in different reports, the following four technical features are consistent.

1. Decentralization (): The left side of Figure 1 describes the centralized characteristics of today’s financial system, and the right side describes the emerging decentralized financial system, which has no intermediaries and all The rights and obligations of nodes are equal. If any node stops working, it will not affect the overall operation of the system;

2. Trustless: All nodes in the system can be rented and bumped without trust. Transaction, because the operation of the database and the entire system is open and transparent, and within the rules and time range of the system, nodes cannot deceive each other;

3. Collective maintenance (Maintain): The system is It is jointly maintained by all nodes with maintenance functions, and everyone in the system participates in the maintenance work;

4. Reliable Database (ReliableDatabase): Every node in the system has the latest complete database Copying or modifying the database of a single node is invalid because the system will automatically compare and consider the same data record that appears the most times to be true.

The blockchains of projects such as Bitcoin, Ethereum, and DECENT all have these characteristics.

② What blockchain technology application development platforms are currently available in China

The so-called blockchain technology, referred to as BT (Blockchain technology), is also called distributed ledger technology. An Internet database technology characterized by decentralization, openness and transparency, allowing everyone to participate in database records.

③ What exactly is blockchain

Let’s talk about some basic concepts first.

The network said that blockchain is a new usage model of computer technologies such as distributed data storage, point-to-point transmission, consensus mechanisms, and encryption algorithms. 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.

ThenSome people think that this kind of low-probability event can use any technical means to avoid individual risks, and the data is not just handed over 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 results?

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. Because of these characteristics, the person handling my data request could record the information for me, but they had no idea who I was or what I was doing.

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.

To academically interpret the words for each part of the data in the chunkDuan, 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 marked with a page number, the second page contains the content of the first page, the third page contains the content of the first and second pages. 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 pay back 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 and inefficiency, which 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 an article titled "Bitcoin: A Peer-to-Peer Electronc Cash System" paper, 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. Just like the writing of the 66 books 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 initial and largest useIt's 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 greatly 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.

The eID network identity operation agency guided by the Third Research Institute of the Ministry of Public Security is jointly developing a "digital identity chain" with Gongyilian, which will be issued to Chinese citizens based on the citizen's identity number as the root and cryptographic algorithm. 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 and trading, traditionalThe stock issuance process is long, costly and complex. 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 handles the issuance on its own through smart contracts, and the regulatory authorities review and verify it uniformly. Investors It is also possible to bypass intermediaries and proceed directly.

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.

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 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.

In this shift from traditional technology to blockchainDuring the experiment, we found that when certain scenarios have stronger demands for traceability, tamper-proofing, and decentralization, but do not have high requirements for the weaknesses of the blockchain (such as performance), such areas are quite suitable for combining zones. 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 equivalent to a disintermediated 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.

④Which one is better to use, blockchain or database?

Blockchain is a computer system with distributed data storage, point-to-point transmission, consensus mechanism, modular encryption algorithm, etc. New application models of technology. Blockchainn), is an important concept of Bitcoin.

It is essentially a decentralized database. At the same time, as the underlying technology of Bitcoin, it is a series of correlations using cryptographic methods. Data block, each data block contains a batch of Bitcoin network transaction information, used to verify the validity of its information (anti-counterfeiting) and generate the next block.

(4) Extended reading of the most commonly used blockchain database

Most public blockchain chains are limited by scalability. The biggest feature of blockchain technology is decentralization, which requires all ledgers in the network to handle the accounting process. Distributed accounting has high security, low misoperation rate, and is also politically neutral and correct.

However, while blockchain technology embraces these characteristics, it sacrifices scalability, cannot meet personalized supervision, and is slightly insufficient in protecting data privacy. Moreover, as the number of ledgers increases, the interaction delay will increase exponentially, which means that the more ledgers in the blockchain network, the higher the latency will be.

⑤ What is Ethereum? What is the relationship between Ethereum and the blockchain?

What is Ethereum:

Ethereum is a technology based on Bitcoin and concepts applied to computer innovations. Ethereum itself imitates many of Bitcoin's technologies to maintain the computer platform. Blockchain technology is one of them.
The Ethereum platform can safely run any program that users want.

The advantages of Ethereum over other competing currencies

Before the emergence of Ethereum, there were already some digital currencies that imitated Bitcoin. However, these projects themselves have certain shortcomings and can only support one or several specific applications at the same time. (A better digital currency trading platform is in "Bihui")

However, the reason why Ethereum can surpass the limitations of these previous projects is because of the core idea of ​​Ethereum.

What Ethereum wants to implement is a blockchain protocol with a built-in programming language. Since it supports programming languages, theoretically any blockchain application can be defined in this language and then serve as a An application that runs on the Ethereum blockchain protocol.

Ethereum is designed to be very flexible and adaptable.

Ethereum aims to combine the strengths of blockchain technology in order to add the advantages of blockchain, such as decentralization, openness and security, to almost all computing fields. .

Ethereum’s blockchain applications

Ethereum has many blockchain applications, such as gold and stock digital applications, financial derivatives applications, DNS and digital Certification and more.

Ethereum has been implemented by many startup companies in more than 100 blockchain applications.

Ethereum is also closely watched by some financial institutions, banking consortiums (such as R3), and large companies like Samsung, Deloitte, RWE and IBM, which has also given rise toA number of blockchain applications have been developed, such as simplifying and automating financial transactions, merchant loyalty index tracking, gift cards designed to decentralize electronic transactions, etc.

The relationship between Ethereum and blockchain:

Ethereum is a programmable blockchain.

Ethereum does not give users a series of preset operations (such as Bitcoin transactions), but allows users to create complex operations according to their own wishes.

In this way, Ethereum can be used as a platform for many types of decentralized blockchain applications, including but not limited to cryptocurrency.

Like other blockchains, Ethereum also has a peer-to-peer network protocol. The Ethereum blockchain database is maintained and updated by numerous nodes connected to the network. Each network node runs an Ethereum emulator and executes the same instructions. Therefore, people sometimes refer to Ethereum as the "world computer".

⑥ Inventory of the top ten most profitable blockchain APPs. Making money by mining is so simple!

As network technology becomes increasingly mature, the word blockchain is mentioned by more and more people. In 2018, blockchain became the first choice project of many investors, and the number of mobile blockchain software is also gradually increasing. From dozens in 2013 to hundreds or even thousands of blockchain companies in 2019, we can see how hot the blockchain market is. In the minds of many friends, blockchain is something that allows one to make money. Yes, blockchain does allow many people to make money, but there are also many unscrupulous fake companies in the blockchain market. In the name of blockchain, it is actually a deceptive business. So friends, when playing with blockchain, you should also keep your eyes open and choose a formal and trustworthy platform!

Today I have collected and sorted out 10 recently popular blockchains for you. Chain software, these platforms are all real and reliable, and each platform has a large number of users. If you are also a friend who likes blockchain, then don’t miss the content I bring!

After understanding the blockchain, let’s start the text. Content, bringing you an inventory of the ten most profitable blockchain software↓↓↓↓↓