In previous blockchain100 sessions, we introduced some of the basic concepts of blockchain. We also know that blockchain has gone through three phases so far. Up to now, blockchain can be divided into different categories according to different classification criteria. In this issue, we will focus on the classification of blockchain.

1

The 3 phases of blockchain

About the 3 phases of blockchain, some concepts are obtained in the book “Blockchain Decryption: Building the Next Generation Of Credit-based Internet” :

Blockchain 1.0: Programmable currency

Blockchain technology came into being with the creation of Bitcoin, and its initial scope of application focused entirely on digital currencies. The emergence of Bitcoin first brought blockchain to the attention of the public, and later produced litecoin, Ether, Dogecoin and other “copycat” digital currencies. The advent of programmable money makes it possible for value to flow directly over the Internet. Blockchain constitutes a new, decentralized digital payment system that is captivated by currency transactions anytime, anywhere, seamless cross-border payments, and low-cost decentralized systems. The emergence of such a new digital currency has a strong impact on the financial system.

Blockchain 2.0: Programmable finance

Influenced by digital currencies, people are beginning to expand the application of blockchain technology to other financial fields. Based on the programmable characteristics of block chain technology, people try to add the idea of “smart contract” to block chain, forming programmable finance. With the support of the contract system, the application of blockchain is beginning to expand from a single currency to other financial areas involving the function of contracts. The emergence of new concepts such as color coin, Bitcoin, Ethereum, and contract coin has made blockchain technology prominent in many financial fields, including stocks, clearing, and private equity. At present, many financial institutions are beginning to study blockchain technology and try to apply it to reality, and the existing traditional financial system is being overturned.

Blockchain 3.0: a programmable society

With the further development of blockchain technology, its “decentralized” function and “data security” function have gradually received attention in other fields. People are beginning to realize that the application of blockchain may not only be limited to the financial field, but also can be expanded to any field where there is a demand. Therefore, in addition to the financial field, block chain technology has been applied to notary, arbitration, audit, domain name, logistics, medical care, mail, authentication, voting and other fields, and the application scope has been expanded to the whole society. In this application stage, people try to use blockchain to subvert the lowest protocol of the Internet, and try to apply blockchain technology to the Internet of Things, so that the whole society will enter the era of intelligent Internet and form a programmable society.

2

The four categories of blockchain

1. Based on the network scope

According to the scope of network, it can be divided into public chain, private chain and alliance chain.

(1) Public chain

The so-called public is completely open to the outside world, anyone can be used arbitrarily, without the setting of authority, there is no identity authentication and so on, not only can be used arbitrarily, and all the data can be viewed arbitrarily, completely open and transparent.

Bitcoin is a public chain network system, everyone in the use of bitcoin system, only need to download the corresponding software client, create wallet address, transfer transactions, mining and other operations, these functions can be freely used.

With no third party management at all, public chain systems rely on a set of pre-agreed rules that ensure that each participant can initiate reliable transactions in a distrustful network environment. Generally speaking, all systems that require public participation and ensure the openness and transparency of data to the maximum extent are applicable to the public chain, such as digital currency system, crowd funding system, financial transaction system, etc.

It should be noted that in the environment of public chain, the number of nodes is not fixed, whether the node is online or not can not be controlled, and even whether the node is a malicious node can not be guaranteed. When we explained the general workflow of blockchain, we mentioned a question. In this case, how do we know that data is confirmed by the majority of nodes? In fact, in the public chain environment, there is no good solution to this problem. At present, the most appropriate approach is to continuously synchronize with each other. Finally, most nodes in the network are synchronized with the same block data and the chain formed is recognized as the main chain, which is also known as the final consistency.

(2) Private chain

Private chain is a concept opposite to public chain. The so-called private chain refers to the system that is not open to the outside world but only used within the organization, such as enterprise bill management, accounting audit, supply chain management, etc., or some government management systems. In the use of private chains, there are usually registration requirements, that is, the need to submit identity authentication, and a set of rights management system. Some friends may have questions, although bitcoin, Ethereum and other systems are public chain systems, but if these systems are built in a LAN that is not connected with the external network, this is not a private chain? Spread from network scale, can calculate, because as long as the network and the network isolation, who has been in use, but due to the use of the system itself and no authentication and permission Settings, so from a technical point of view, this kind of situation can be used only male chain system with its private client test network, Ethereum, for example, can be used to build private chain environments, which can often be used to test public chain systems, but also for enterprise applications.

In the private chain environment, the number of nodes and the state of nodes are usually controllable. Therefore, in the private chain environment, there is generally no need to screen the packers of block data through competition, and a more energy saving and environmental protection method can be adopted, such as PoS (Proof of Stake, DPoS (Delegate Proof of Stake), PBFT (Practical Byzantine Fault Tolerance algorithm), etc.

(3) Alliance chain

League chain network range between the chain of public and private chain, is often used in more than one member role of the environment, such as payment and settlement between Banks and enterprises between logistics and so on, these scenarios are often by members of different permissions, as well as private chain, chain alliance system generally is also has the identity authentication and permission Settings, Moreover, the number of nodes is often fixed, which is suitable for transactions between enterprises or organizations. The alliance chain does not have to be completely controlled. For example, in the government system, if some data can be made public, it can be partially opened up.

Since alliance chains are generally used between distinct organizations, the number and status of nodes are controllable, as is the case with private chains, and they are usually more energy-efficient and environmentally friendly consensus mechanisms.

2. Based on the deployment environment

(1) main chain

The main chain is a real blockchain system that is deployed in a production environment. The software goes through a lot of internal testing before it is released to find possible bugs, and is used for internal demos to see the effect. The main chain can also be said to be a blockchain network composed of formal clients. Only the main chain can be truly promoted and used, and the design of various functions is relatively perfect. In addition, sometimes the blockchain system forks for a variety of reasons, such as temporary small forks during mining, and the longest original chain is called the main chain.

(2) Test chain

This is very well understood, is the developer in order to facilitate everyone to learn to use and provide test purposes of the blockchain network, such as Bitcoin test chain, Ethereum test chain, etc.. Of course, you don’t have to be a blockchain developer to provide a test chain, but you can build your own test network. The functional design of the test chain can be different from that of the main chain in the production environment. For example, the proof of work algorithm is used in the main chain for mining, and the algorithm can be changed in the test chain for easier testing.

3. Based on the interconnection type

(1) single chain

Any blockchain system that can run independently can be called “single chain”, such as bitcoin main chain and test chain. Ethereum main chain, test chain; Litecoin’s main chain and test chain; Such as the federation chain built by Fabric in the super ledger project. These blockchain systems have complete component modules and form a system of their own. Note that some software systems, such as ethereum-based crowdfunding systems or financial guarantee systems, can only be considered smart contract applications, not independent blockchain systems. The operation of applications requires the support of independent blockchain systems.

(2) Side chain

Side chain is a cross-chain technology of blockchain system. This concept is mainly initiated by the Bitcoin side chain. With the development of technology, in addition to bitcoin, there are more and more blockchain systems, each of which has its own advantages and characteristics. How to combine different chains to open up information islands and complement each other? Side chain is one of those technologies.

In the case of Bitcoin, the bitcoin system is mainly designed to implement digital cryptocurrencies, and the business logic is solidified, so it is not suitable for implementing other functions, such as financial smart contracts, small quick payments, etc. However, bitcoin is the largest public blockchain system currently in use and has considerable advantages in terms of reliability and decentralized guarantee. Then how to make use of the advantages of bitcoin network to run other blockchain systems? Consider on the existing currency block chain, to build a new block chain system, the new system can have many COINS have no function, such as private transaction, fast payment, intelligent contracts, signature cover amount, etc., and can carry on the exchange with the currency of the main block chain, in simple terms, side chain is based on anchor currency new block chain. The side chains that anchor Bitcoin, currently ConsenSys’ BTCRelay, Rootstock and BlockStream’s element chains, among others. It should be noted that the side chain itself is a blockchain system, and the side chain does not have to take Bitcoin as the reference chain. This is a general technical concept. For example, Ethereum can be used as the reference chain of other chains, or anchoring with other chains as the side chain itself. In fact, apart from the concepts of chain and network, different software provide interfaces to each other to enhance the functional complementarity between software. Let’s take a look at the schematic diagram of side chain:

Through this simple diagram, we can see that block chain system with side chain system itself is an independent system of chain, can be carried out in accordance with the certain agreement between data interaction, in this way, the side chains can play the role of an extension of main chain function, many in the main chain is not convenient to implement function can be realized in the side chain, The side chain in turn enhances its reliability through data interaction with the main chain.

(3) Interconnection chain

Nowadays, our life can be said to be almost inseparable from the Internet, just interconnection, the energy has been so great.

The same is true of blockchain. At present, various blockchain systems keep emerging, some just realize digital currency, some realize smart contract, some realize financial transaction platform, some are public chain, some are alliance chain, and so on. So many chains, colorful, different functions, rich imagination, constantly refreshing more novel application play. So what would happen if these chain systems could be connected to each other? Unlike traditional software, chain block application has unique properties, such as data cannot be tampered with sex, certificate of integrity, automatic, intelligent network consensus agreement, etc., from the original programmable digital currency to possible future block chain society, these not only change the way of life services, will promote social governance structure to change, if each strand is a nervous, Once connected, like a nervous system, it will bring a new level of intelligence to our social development.

In addition, from the technical point of view, the interconnection between blockchain systems can be complementary to each other. Each type of system has its advantages and disadvantages, so it can complement each other in function and even verify each other, which can greatly enhance the reliability and performance of the system.

4. By application scope

According to the scope of application: basic chain, industry chain. As the saying goes, currency is about consensus, while chain is about ecology. According to the scope of ecological application, blockchain can be divided into the following two types:

(1) Basic chain

Typical cases: ETH, EOS

Features: The so-called basic chain, in a few meters of understanding, is a block chain that provides various low-level and common development protocols and tools to facilitate developers to quickly develop various DApps on it. Generally, the public chain is mainly used.

In an analogy to reality, we often say that the basic chain is the operating system. This may not be strictly accurate, as different base chains are positioned differently. For example, ETH and EOS may be more like operating systems, while ontology and NULS are more like custom protocols.

(2) Industry chain

Typical cases: BTM, GXS, SEER

Characteristics: There seems to be no unified definition of the so-called industry chain in the industry. Jimmy thinks it is a basic protocol and tool specially customized for some industries, which is inferior to the basic chain in the underlying technology. If the basic chain as a general chain, then you can understand the industry chain as a special chain.

Industry chain is similar to some industry standards in our daily life. For example, BTM is the asset public chain, GXS is the data public chain, and SEER is the prediction public chain.

When dividing by application scope, there should also be a third category: application chain. But I always feel that the app chain or directly called DAPP, with the chain is not comparable.

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Content source: Vernacular blockchain, Blockchain Decryption: Building the Next Generation Internet based on credit, Block King, block chain investment strategy

Sorting: Cynthia

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