区块链系统存在系统管理员吗,区块链权限管理系统

区块链系统存在系统管理员吗？答案是肯定的，区块链系统中必须存在系统管理员，他们负责维护区块链系统的安全性和可靠性。而且，区块链权限管理系统也是必不可少的，它可以为区块链系统提供安全性和可靠性的保障。今天，就让我们一起来了解一下区块链权限管理系统的三个关键词：身份认证、角色权限、审计日志。

身份认证是区块链权限管理系统中最重要的一个关键词，它指的是区块链系统中用户的身份认证，用于确定用户的身份，以便系统能够根据用户的身份来授予不同的权限。身份认证可以采用多种方式实现，比如通过用户名密码、数字证书、双因子认证等，以确保用户的身份安全。

角色权限是区块链权限管理系统中的另一个关键词，它指的是系统中不同角色的权限管理。比如，系统中可以定义不同的角色，比如管理员、用户等，并为不同角色分配不同的权限，以便控制用户的访问权限。此外，角色权限还可以用来实现不同级别的安全访问控制，以确保系统的安全性。

审计日志是区块链权限管理系统中的最后一个关键词，它指的是系统中的审计日志，它记录了用户在系统中的所有操作，以便查看用户的行为。审计日志可以帮助管理者了解用户的行为，从而及时发现潜在的安全问题，以及及时发现用户的恶意行为，从而及时采取有效的措施，确保系统的安全性。

总的来说，区块链权限管理系统中的三个关键词：身份认证、角色权限、审计日志，是系统安全性和可靠性的重要保障。只有当这三个关键词都得到充分的重视，才能确保区块链系统的安全性和可靠性。

1. What are the main features of blockchain

Decentralization
Due to the use of distributed computing and storage, there is no centralized hardware or management organization , the rights and obligations of any node are equal, and the data blocks in the system are jointly maintained by nodes with maintenance functions in the entire system.
Openness
The system is open. In addition to the private information of the transaction parties being encrypted, the blockchain data is open to everyone. Anyone can query the blockchain data and information through the public interface. Develop related applications, so the entire system information is highly transparent.
Autonomy
The blockchain adopts consensus-based specifications and protocols (such as a set of open and transparent algorithms) to enable all nodes in the entire system to exchange data freely and securely in a trustless environment, making Trust in "people" has been changed to trust in machines, and any human intervention has no effect.
Information cannot be tampered
Once the information is verified and added to the blockchain, it will be stored permanently. Unless more than 51% of the nodes in the system can be controlled at the same time, modifications to the database on a single node will not be allowed. is invalid, so the data stability and reliability of the blockchain are extremely high.
Anonymity
Because the exchange between nodes follows a fixed algorithm, the data interaction is trustless (the program rules in the blockchain will judge whether the activity is valid by itself), so the counterparty does not need to disclose it through the The way of identity allows the other party to trust itself, which is very helpful for the accumulation of credit

2. What is the immutability of the blockchain

Usually, the specific meaning of immutability is Something doesn't change over time. Through the blockchain, the data provider can prove that the data it provides has not been changed, and the data recipient can be sure that the data it receives has not been tampered with. Jinwowo-Blockchain Technology
Blockchain is also based on the same principle. For data tamperers, it is not difficult to tamper with data. The difficult part is how to prevent others from discovering the tampering. As long as others can quickly verify that the data has been tampered with, it means that the tampering has failed. This in disguise increases the difficulty of modifying something.

3. What is blockchain technology? What are the core components of blockchain technology?

From a technical perspective and an architectural perspective, let me tell you about it in popular language. My understanding of blockchain.

What exactly is blockchain? Block chain, in a word, blockchain is a storage system, and the storage system is more detailed. Block chain is a distributed storage system without an administrator, and each node owns all data.

What do common storage systems look like?

First, let’s take a look at how to ensure high availability?

Ordinary storage systems usually use "redundancy" to solve high availability problems. As shown in the figure above, if the data can be restoredBy making several copies and redundant them in multiple places, high availability can be ensured. If the data in one place is down, there will still be data in another place. For example, the master-slave cluster of MySQL has this principle, and the RAID of the disk also has this principle.

Two points that need to be emphasized here are: data redundancy, which often causes consistency problems

1. For example, in the master-slave cluster of MySQL, there is actually a delay in reading and writing. Sometimes, it actually means that there is inconsistency between reading and writing for a short period of time. This is a side effect of data redundancy.

2. The second point is that data redundancy often reduces writing efficiency, because data synchronization also consumes resources. If you look at single-point writing, if two slave libraries are added, the writing efficiency will actually be affected. Ordinary storage systems use redundancy to ensure high data availability.

Then the second question is, can an ordinary storage system perform multiple writes?

The answer is yes, for example, take this picture as an example:

In fact, MySQL can do a dual-master master-slave synchronization, dual-master master-slave synchronization, two nodes , and can be written at the same time. If you want to build a multi-computer room and multi-active data center, in fact, multi-computer room and multi-active data center also requires data synchronization. What should be emphasized here is that multi-point writing often leads to consistency issues of write-write conflicts. Taking MySQl as an example, assuming that the attribute of a table is an auto-increment ID, then the data in the database is now 1234, then one of the nodes When writing, a piece of data is inserted, it may become 5. Then these 5 pieces of data are synchronized to another master node. Before the synchronization is completed, if another writing node also inserts a piece of data, it will also generate A piece of data with an auto-incrementing ID of 5 is obtained. Then, after it is generated, it is synchronized to another node, and then when the synchronized data arrives, it will conflict with the two local 5s, and the synchronization will fail, which will cause write consistency conflicts. This problem will occur if there are multiple writes.

How to ensure consistency when writing multiple points?

Weixin’s “Swan Master Class” will give you more technical work

4. How to analyze the blockchain in a simple and easy-to-understand manner

For many people I mean, maybe as soon as I saw such lofty vocabulary and such obscure technical explanations, and then measured my knowledge reserves, I was scared to step back a little.

In a word, it is a special distributed database. First of all, the main function of blockchain is to store information. Any information that needs to be saved can be written to the blockchain and read from it, so it is a database. Secondly, anyone can set up a server, join the blockchain network and become a node. In the world of blockchain, there is no central node. Every node is equal and stores the entire database. You can write/read data to any node, because all nodes will eventually be synchronized to ensure that the blockchain is consistent.

Blockchain

The biggest feature of blockchain: distributed databases are not a new invention, and such products have long been on the market. However, blockchain has a revolutionary feature. The blockchain has no administrators and is completely centerless. Other databases have administrators, but blockchain does not. If one wanted to add auditing to the blockchain, it would not be possible because it is designed to prevent the emergence of a central authority. It is precisely because it cannot be managed that the blockchain cannot be controlled. Otherwise, once big companies and large groups control the management, they will control the entire platform, and other users will have to take orders from them. However, without an administrator, everyone can write data into it. How can we ensure that the data is trustworthy? What should I do if I am changed by a bad person? Please read on, this is the wonderful place of blockchain.

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5. Brief understanding of blockchain

Blockchain is an important concept of Bitcoin, the underlying technology and infrastructure of Bitcoin, and a distributed data storage , point-to-point transmission, consensus mechanism, encryption algorithm and other new application models of computer technology.
In a narrow sense, blockchain is a chain data structure that combines data blocks in a sequential manner in chronological order, and is distributed cryptographically to ensure that it cannot be tampered with or forged. Account book.
In a word, it is a special distributed database.

A very important understanding is decentralization

In the world of blockchain, there is no central node. Every node is equal and stores the entire database. Any reading is parallel and transparent.
Blockchains have no administrators, and the blockchain format was first applied to Bitcoin as a solution for making databases secure without the need for trust from administrative agencies.
So how did he obtain anti-counterfeiting?

Blocks and Hash have a one-to-one correspondence. If someone modifies a block, the Hash of the block will change.
So he is the only one!
The machine that calculates Hash is called a mining machine, and the person who operates the mining machine is called a miner.
The block header contains a difficulty coefficient (difficulty), which determines the difficulty of calculating the Hash.
It takes about 1 billion calculations to count once.

Blockchain mainly solves the trust and security issues of transactions, so it targets thisThe question raised four technological innovations:
The first one is called distributed ledger, which means that transaction accounting is completed by multiple nodes distributed in different places, and each node records a complete account, so they All can participate in supervising the legality of transactions and can also jointly testify for them. Different from traditional centralized accounting solutions, no node can record accounts independently, thus avoiding the possibility of a single accounting person being controlled or bribed to record false accounts. On the other hand, since there are enough accounting nodes, theoretically, the accounts will not be lost unless all nodes are destroyed, thereby ensuring the security of the accounting data.
The second one is called asymmetric encryption and authorization technology. The transaction information stored on the blockchain is public, but the account identity information is highly encrypted and can only be accessed with authorization from the data owner. This ensures data security and personal privacy.
The third one is called the consensus mechanism, which is how all accounting nodes reach a consensus to determine the validity of a record. This is both a means of identification and a means of preventing tampering. Blockchain proposes four different consensus mechanisms, which are suitable for different application scenarios and strike a balance between efficiency and security. Taking Bitcoin as an example, it uses proof of work. Only when more than 51% of the accounting nodes in the entire network are controlled, it is possible to forge a non-existent record. When there are enough nodes joining the blockchain, this is basically impossible, thus eliminating the possibility of fraud.
The last technical feature is called smart contracts. Smart contracts are based on these trustworthy and non-tamperable data and can automatically execute some predefined rules and terms. Take insurance as an example. If everyone's information (including medical information and risk occurrence information) is true and trustworthy, it will be easy to automate claims settlement in some standardized insurance products.

A person signed by Satoshi Nakamoto proposed a revolutionary idea: let’s create a currency that is not controlled by the government or anyone else!
----The origin of Bitcoin.
Blockchain technology has extremely broad application prospects, especially in digital currency, cross-border payments, etc. in the financial field. Previously, it was reported that the People’s Bank of China is expected to become the first central bank to develop digital currency and carry out real-life applications.
35 Internet: The company and CICC Online have signed a letter of intent to cooperate and plan to jointly carry out Bitcoin projects, and blockchain technology is the core of Bitcoin.
Hundsun Electronics: is trying to establish a digital bill system based on the alliance chain using blockchain technology.
Feitian Integrity: The company once stated on the interactive platform that it currently has certain technical reserves and research in blockchain technology. The company will actively participate in digital currency and other blockchain technology industries in the future.
Wintime: On April 11, it was stated on the investor relations interactive platform that the company currently has technical reserves in this area, but it is in the initial stage.
Judging from the current situation, my country’sThe vast majority of blockchain technology applications in municipal companies are still in the research stage, and the implementation and promotion of projects have yet to be tested over time.

6. The most straightforward explanation of blockchain

In recent years, the term "blockchain" has become a hot topic, and news media have reported on it, but everyone may not understand the blockchain. The understanding of blockchain is still in the foggy stage. Today we will unveil its mystery.

In fact, the essence of blockchain is very simple and can be explained in one sentence: decentralized distributed database.

The main function of the blockchain is to store information. Anyone can write information and read it at the same time, so it is a public database.

Characteristics of blockchain

Distributed database technology has long existed in the market, but the difference is that although blockchain is also a distributed database , but it has no administrator and is completely decentralized.

Decentralization is a disruptive feature of blockchain technology. It does not require a centralized agent and realizes a direct point-to-point interaction, enabling high-efficiency, large-scale, and information interaction without a centralized agent. way becomes reality.

However, without an administrator, everyone can write data into it. How can we ensure that the data is trustworthy? What should I do if I am changed by a bad person? The designers have already thought of this, which proves that blockchain is a truly epoch-making product.

Block

The blockchain is composed of blocks. Blocks are much like database records. Every time data is written, a block is created.

Each block contains two parts:

Block header (Head): records the characteristic value of the current block
Block body (Body): actual Data
The block header contains multiple characteristic values ​​of the current block.

Generation time
Hash of the actual data (i.e. block body)
Hash of the previous block
...
Every time in the system Each node has the latest complete database copy. 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. At the same time, every step of the data record will be retained on the blockchain, and the information at each step can be traced.

Here, you need to understand what a hash is, which is necessary to understand the blockchain.

The so-called "hash" means that the computer can calculate a characteristic value of the same length for any content. The hash length of the blockchain is 256 bits, which means that no matter what the original content is, a 256-bit binary number will be calculated in the end. And it can be guaranteed that as long as the original content is different, the corresponding hash must be different.of.

For example, the hash of the string 123 is (hexadecimal), which is 256 bits when converted to binary, and only 123 can get this hash. (Theoretically, it is possible for other strings to get this hash, but the probability is extremely low and can be approximately considered impossible.)

Therefore, there are two important inferences.

Corollary 1: The hash of each block is different, and the block can be identified by the hash.
Corollary 2: If the content of the block changes, its hash will definitely change.

The immutability of hashes

Blocks and hashes have a one-to-one correspondence, and the hash of each block is for the "block header" (Head) computational. That is to say, the characteristic values ​​​​of the block header are connected together in order to form a very long string, and then the hash is calculated on this string.

Hash = SHA256 (block header)

The above is the calculation formula of block hash. SHA256 is the hash algorithm of the blockchain. Note that this formula only includes the block header and not the block body. In other words, the hash is uniquely determined by the block header.

As mentioned earlier, the block header contains a lot of content, including the hash of the current block body and the hash of the previous block. This means that if the content of the current block body changes, or the hash of the previous block changes, it will definitely cause the hash of the current block to change.

This is of great significance to the blockchain. If someone modifies a block, the hash of the block changes. In order for subsequent blocks to still be connected to it (because the next block contains the hash of the previous block), the person must modify all subsequent blocks in sequence, otherwise the modified block will be removed from the blockchain . Due to the reasons mentioned later, hash calculation is very time-consuming, and it is almost impossible to modify multiple blocks in a short period of time, unless someone controls more than 51% of the computing power of the entire network.

It is through this linkage mechanism that the blockchain ensures its own reliability. Once the data is written, it cannot be tampered with. This is just like history, what happened happened, and it can’t be changed from now on.

7. What is Web3.0 and what benefits can it bring? What is the connection between Web3.0 and blockchain?

To put it simply, Web3.0 hopes to break the barriers of Internet giants and make User data, information and value truly belong to you, and this is in line with the characteristics of the Metaverse. Many people in the industry also regard Web3.0 as the basis for creating the metaverse. It has strong practical guiding significance and commercial value for the metaverse. The Metaverse is a huge world full of potential. Web3.0 is the fundamental driving force for the creation and continued growth of the Metaverse, and its development process also determines the time when the Metaverse will be launched to some extent. At onceAt present, Web3.0 does not just stay in the conceptual field. In fact, many related applications have been produced. The Metaverse is not the focus of our discussion in this article. 2020 is definitely an epoch-making year for the blockchain field. The explosion of DeFi has made more and more people pay attention to the concept of decentralization, which also It will be the next frontier in the Internet, and the movement toward network decentralization is Web 3.0.

As we all know, our Internet has experienced the Web1.0 era and the Web2.0 era before. Web1.0, the original Internet, was just a web network, while Web2.0 has evolved into a social network. Users Start generating your own content through social media, but what does it mean for the upcoming Web3.0 era? Why does web3.0 need blockchain technology? First of all, Web1.0 can be understood as the first generation of the Internet. In the 1990s, computers had just become popular and the concept of the Internet had just emerged. The Internet at that time was still very basic. You could only simply open a web page and browse information. It is completely passive to receive information. You can read whatever is written on the website. In the Web 1.0 era, people obtained information from the Internet, but most of this information was read-only. Typical representatives of Web 1.0 are domestic portals such as Sina and NetEase.

Then came the Web2.0 era. Web2.0 is also called a social network. The way you surf the Internet now is what Web 2.0 looks like. Users have changed from passively receiving information to being able to publish opinions independently and communicate with other users. Nowadays, the most popular short video platform is a typical representative of Web2.0. People can express their thoughts through personal live broadcast, and users can communicate online at all times through various methods such as likes, comments, and interactions. We are still in Web2 today. In the 0 era, it has moved from the Internet to the mobile Internet, and from the real world to the digital world, which has profoundly changed people's living habits. However, Web2.0 also has many shortcomings.

The first point is that Web2.0 data is stored in the central server, which has security risks. Web2.0 adopts central server management, and user data is stored and managed centrally on the servers of large companies trusted by the majority of users. Data on servers are protected by firewalls, and system administrators are required to manage these servers and firewalls. If there is a successful intrusion by a hacker or some force majeure factors, it is likely to cause data loss and cause heavy losses to customers.

The second point is that the privacy of Web2.0 users cannot be guaranteed. We now live in an Internet era. More and more devices, such as mobile phones, smart watches, and cars, collect our information all the time and connect to the Internet.Storing our information in cloud servers is, of course, a problem that must be faced in the era of big data.

The third point is that Web2.0 needs to rely on a large platform to build trust. Web2.0 has brought infinite convenience to our lives, but it needs to be built on a credible platform. Although it has facilitated our lives, middlemen have huge profit margins, and the profits often come from users. And users did not get enough returns from this.

Finally, Web 3.0 is still difficult to define. It is based on Web 2.0 and can effectively solve these shortcomings of Web2.0, so that the value of the Internet ultimately belongs to users, and blockchain technology is Web3. 0 driving force. The reason why we say this is because the blockchain actually provides two core capabilities, namely a fairer and more open participation method, that is, the openness of the organizational form. and assets being settled contractually and circulated reliably and without hindrance. These two capabilities are based on various basic characteristics of the blockchain. In other words, the blockchain is used as an underlying benefit distribution system, and the openness of the organizational form can be supported on top of the blockchain. Let all parties involved unconditionally trust the distribution method and reach a consensus on the distribution method. It can also ensure the reliable execution of benefit distribution. Therefore, blockchain is crucial to Web3.0 and is an essential infrastructure for Web3.0 applications.

Web3.0 will be more user-centered, so digital identity authentication and privacy protection, as well as data confirmation and decentralization are the keys to its development. This has a natural fit with blockchain technology and is one of the reasons why blockchain is called the Internet of Value. With Web 3.0 in the context of the value Internet, the underlying business logic of the Internet will also undergo fundamental changes. In the Web 3.0 era, users do not need to create multiple identities on different centralized platforms as they do today, but can instead create a decentralized universal digital identity system. Relevant user data can be stored in a distributed database, and only users can manage and authorize themselves to perform operations with what identity information, ensuring the user's data rights and value ownership, while protecting privacy and security, plus smart contracts, etc. Technology also facilitates fairer business models.

So what are the benefits of web3.0? First of all, the network is composed of many independent nodes. Even if one or two nodes are compromised by hackers, there are still thousands of nodes storing safe and effective data. Even if a node crashes, the blockchain network can still operate normally. Secondly, the decentralized network completely eliminates the middleman. There is no need to trust any company or any third party. In the web3.0 world, code is law. Just trust the mathematical and computational principles upon which blockchains are built. Again, the consensus mechanism of the blockchain does not require a centralized authority to make decisions. All nodes in the network that save data are driven by incentives.Come together and make decisions together. Then blockchain brings a new economic model to Web3.0. It’s no longer companies with centralized servers like Google and Facebook and Amazon. Blockchain gives value to the network itself and the community members connected to the network through tokens.

The last point is that there will be no need to store large amounts of data on servers in the future, and it will be easier and cheaper to deploy new servers. In fact, after saying so much, one of the features of web3.0 is decentralized operation and decentralized storage. The distributed storage of IPFS FIL is a typical representative in this regard. There is no longer the concept of centralized storage in the Internet, making the Internet faster, more efficient, more secure, and information cannot be tampered with. Encrypted data makes it easier to protect our personal data. In addition, all data in Web3.0 is owned by the user. The user has no right to use it without the user's authorization. At the same time, the user is entitled to a share of the revenue generated by using the data, and the user can enjoy the benefits of the token economy.

The BAT token ecology in the Brave browser, a typical example, has done a good job in this regard. The decentralized model can be applied to any part of the web ecosystem, including web hosting and storage as well as domain name systems and applications and search capabilities. For example, decentralized storage has been a top priority in the encryption field for a long time. The way users store data is the same as using Dropbox or Google Drive today, but there is actually a distributed network on the back end, and the data is stored there. The interesting thing is that anyone can become a storage provider and contribute storage space to the network. In this case, it will be greatly difficult for any centralized organization to block or control the flow of information on the Internet. And any agent that wants to mine and analyze user data will no longer have a single source to mine, but will need to retrieve data from potentially millions of storage locations – and sift through IP packets one by one.

With this, web 3.0 has changed the imbalance of power caused by the current centralized network and put the power of information release back into the hands of individuals. And this was exactly how the Internet pioneers originally envisioned the Internet. In short, Web3.0 can provide services more securely and efficiently, while protecting our personal privacy from being threatened. Currently, Web3.0 has not been widely popularized. With the continuous development of blockchain applications, Web3.0 will gradually become more popular in the future. Integrate into our lives and bring us a more comfortable and secure Internet environment.

8. What is blockchain

Blockchain is a new application model of computer technology such as distributed data storage, point-to-point transmission, consensus mechanism, and encryption algorithm.

Blockchain is an important concept of Bitcoin. It is essentially a decentralized database and serves asThe underlying technology of Bitcoin is a series of data blocks generated using cryptographic methods. Each data block contains information about a Bitcoin network transaction, which is used to verify the validity of its information (anti-counterfeiting) and generate the next one. block.

Some areas where blockchain can be used can be:

▪Smart contracts

▪Securities trading

▪Internet of Things

▪Social communication

▪File storage

▪Proof of existence

▪Identity verification

▪Equity crowdfunding

We can compare the development of blockchain to the development of the Internet itself. In the future, there will be an Internet called finance-internet. Something, and this thing is based on blockchain, its precursor is bitcoin, that is, traditional finance starts from private chains and industry chains (local area network), and the bitcoin series starts from public chains (wide area network), all expressing the same concept - Digital assets (DigitalAsset) eventually converge to an intermediate equilibrium point.

The evolution of blockchain is:

▪ Blockchain 1.0 - digital currency

▪ Blockchain 2.0 - digital assets and smart contracts

▪ Blockchain 3.0 - the implementation of distributed applications in various industries