区块链和码链的区别,区块链 链改

1. Blockchain technology empowers smart upgrading of archives management

How to ensure the security of the archives digitization process and electronic archives

In the context of the country's vigorous promotion of electronic archives management, archives management work has gone through the process from receiving and keeping paper archives to receiving and keeping electronic archives, from managing archive entities to managing archive data, from manual operations to information-based intelligent operations, and from archival resources Decentralized utilization to the transformation of Internet sharing. However, in their long-term preservation activities, archival digital resources will inevitably use conventional technical methods such as copying, updating, and format conversion, key technical methods such as migration, packaging, and simulation, and auxiliary methods such as hard copy output. During these preservation activities, the content, structure (physical structure and logical structure), metadata, etc. of electronic archives may undergo certain changes.

How to ensure the security of the archives digitization process and electronic archives? Blockchain applications have become an important choice to break through bottlenecks.

The application value of blockchain electronic archives

Blockchain technology is applied to electronic archive data management, allowing anyone to independently verify archives, and is suitable for cross-department and cross-region and multiple processes and application scenarios across responsible entities, reducing dependence on the blockchain platform and liability risks, while meeting the certification needs of massive archival digital resources.

01 Electronic archive applications developed through blockchain have improved electronic archive management methods and authenticity assurance methods, and can provide reliable support for the protection of corporate intellectual property rights.

02 Through the application of blockchain electronic files, the electronic files of engineering projects are transformed from paper management to electronic management, improving work efficiency and effectively reducing the corresponding costs of enterprises and project participants in project document management. .

03 Through the application of blockchain electronic archives, the demands of all parties between the industry ecological chain and department levels can be balanced, while emphasizing the transfer of information value between institutions or organizations in the same industry or across industries and departments. (Mutual recognition of evidence) Reduce management costs and improve efficiency while collaborating with work.

04 Through the application of blockchain electronic archives, it can promote the further improvement of archival data archiving business in terms of archiving, storage, transmission, anti-counterfeiting and information security.

Conclusion

In fact, blockchain can be both civil and military. In addition to its application in digital archive management, blockchain technology also has many application cases in the fields of digital government affairs, commodity traceability, supply chain management, intelligent manufacturing and digital collections.

2. The upgrade of blockchain technology enables blockchain applications to be regulated

The upgrade of blockchain technology enables blockchain applications to be regulated
In the Internet era, computers have long proposedMany trusted computing methods are that any blockchain technology node adopts a trusted computing module. Therefore, trusted computing can make it easier to upgrade and iterate technology in distributed networks.
In terms of the real-name system of blockchain technology, there is a blockchain technology laboratory in the United States, and they have proposed many technical solutions for real-name systems. For example, the current blockchain technology is point-to-point. In many countries, such as South Korea, each person has an electronic certificate, and real-name electronic certificates must be used for signatures during transactions. Of course, there are simpler solutions. We can store the IP address of the entire device as part of the transaction on the blockchain application.
In this way, the entire blockchain technology transaction can realize the real-name system of the technology. So this is an optional real-name system. We can build a real-name blockchain application network or an anonymous blockchain application network.
Super Key is also a major advancement in the current development of blockchain technology. Because it is a distributed network, how do we supervise it and how do we control it? In cryptography, we call it multi-signature.
We (yunbaokeji) design a different blockchain application network. If it is a blockchain application network used by a bank, we can design a super key. The keys of all nodes must be together with the super key to generate a wallet.
Then this super key must be in the hands of regulators or certain institutions, who can have limited control over blockchain applications. For example, currently the data on blockchain applications cannot be deleted, so the super key actually allows powerful organizations to modify the distributed network.
So what kind of technology is blockchain:
(1) Distributed decentralization,
(2) No need to trust the system,
(3) Unable to Tampering and encryption security. I know these words individually, but what do they mean together?
1. Distributed decentralization. This is talked about all over the Internet. Needless to say, in short, there is no longer a need for a central server. Everyone’s data is obtained from this server. Instead, The data is placed on N devices connected to the Internet, and everyone can download and store it.
2. No need to trust the system. Do you trust banks? Because the bank is recognized and established by the state, the blockchain implements a trust method that does not require a third party. N devices on the Internet are used to store data, and everyone can verify the data. As long as more than half of the people think you are right, you are right. No one person or organization can modify more than half of the content on the Internet. If you don't believe in others, you should always believe in your own verification results. If you don't believe in yourself, then congratulations, you are a great philosopher.
3. Non-tampering and encryption security
Blockchain uses a series of technologies, such as SHA256 and RIPEMD160 and other cryptographic algorithms to ensure non-tampering and encryption security. For example, 0101100011101110 represents a character. The algorithm requires shifting 4 bits to the left, supplementing with 0, throwing away the 4 bits on the left, and adding 4 0s to the right. As a result, how can we deduce the original value based on the result? Of course this is just a simple example.

3. What problems does the blockchain solve?

If you can explain it in one sentence: decentralization.
Blockchain is a new application model of computer technology such as distributed data storage, point-to-point transmission, consensus mechanism, and encryption algorithm.
The so-called consensus mechanism is a mathematical algorithm that establishes trust and obtains rights and interests between different nodes in the blockchain system.
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.
Broadly speaking, blockchain technology uses block chain data structures to verify and store data, uses distributed node consensus algorithms to generate and update data, and uses cryptography to ensure the security of data transmission and access. A new distributed infrastructure and computing method that uses smart contracts composed of automated script codes to program and manipulate data.
Advantages:
1) The algorithm is simple and easy to implement;
2) Nodes can reach consensus without exchanging additional information;
3) Destroying the system requires a huge cost .
Disadvantages:
1) Waste of energy;
2) Block confirmation time is difficult to shorten;
3) The new blockchain must find a different hashing algorithm, Otherwise, you will face Bitcoin’s computing power attack;
4) It is easy to produce forks and need to wait for multiple confirmations;
5) There is never finality, and a checkpoint mechanism is needed to make up for finality.

4. (Translation) Basic concepts of Hyperledger official document (3) - Node (Peer)

Hyperledger is a project initiated by the Linux Foundation, aiming to provide an enterprise-level The blockchain application framework facilitates the development of applications based on blockchain technology.

Basic concepts of Fabric

Initially, the application will select a group of peers to generate ledger update proposals. Which peers will be selected based on the endorsement policy, which determines which organizations need to endorse the update proposal before broadcasting the ledger update proposal. This will affect the consensus method. Any organization that cares about whether the update proposal is endorsed will confirm whether the proposal is endorsed before broadcasting the update proposal to the peer and being accepted by the peer.

When a peer endorses a proposal response, it adds its own digital signature to the response and signs the entire response with its own private key. The endorsement content can then be used to prove that the response was generated by a peer from an organization. In our example, if peer P1 belongs to organization 1 (Org1), then endorsing E1 is equivalent to proving that transaction T1 and response R1 on L1 are provided by peer P1 of Org1.

The first phase ends when the application has received a sufficiently signed proposal response.
We noticed that peers may return different information, so the same transaction may have inconsistent return information. This may be due to the fact that responses are generated at different times, by different peers, in different ledger states, and in most cases the application can request an updated proposal response multiple times. Another more serious, but very unlikely, reason is the inconsistent response caused by the uncertainty of the chain code. Uncertainty is the enemy of chaincode and the ledger. If this happens, it will be very serious for the proposed transaction, and the inconsistent proposal response will definitely not be submitted to the ledger. It is impossible for an independent node to know that the transaction result is a non-deterministic transaction. Before detecting a non-deterministic transaction, the transactions must be aggregated and compared (strictly speaking, even this is not enough, but we postpone this discussion to the transaction part, Non-determinism is discussed in detail).

At the end of the first phase, the application can safely discard inconsistent responses to end the transaction process early if it so wishes. We will see later that if an application submits to the ledger with an inconsistent response, it will be rejected.

Process 2 Packaging
The second transaction process is packaging. The key point in the process of the Orderer node is that it receives endorsed proposal transaction responses from many applications. The Orderer sorts transactions and packages a large number of transactions into blocks, and prepares to distribute the blocks to all peers connected to the Orderer, including endorsing peers.

The first role of the orderer is to package ledger update proposals. In the example above, application A1 sends a transaction T1 endorsed by E1 and E2 to Orderer O1. At the same time, application A2 sends a transaction T2 endorsed by E1 to Orderer O1. O1 packages the transaction from A1, the transaction from A2 and other transactions into block B2. We can see that the order of transactions in block B2 is T1, T2, T3, T4, T6, T5, not necessarily in the order of arriving at the orderer node (this example shows a very simple orderer configuration).

The Orderer node will receive ledger update proposals sent by different applications in the network Channel at the same time. The task of the Orderer node is to organize these update proposals in a pre-defined order and package them into blocks to prepare for the next distribution. These blocks will make up the blockchain. Once the Orderer node generates a block of the desired size, or the maximum waiting time is exceeded, the Orderer will send the block to the Peer connected to its specific Channel. The third process will elaborate on this process.

There is no direct relationship between the order of transactions in the block and the order in which transactions arrive at the Orderer node. Transactions can be arranged in any order in the block, and this order is the order in which transactions are executed. The point is that there is a strict ordering of transactions, but the exact ordering is not important.

The strict order of transactions in the block makes Fabric different from the situation in the public chain where a transaction can be packaged into multiple different blocks. In Fabric, this cannot happen. The block generated by multiple Orderers is the final block, because after the transaction is written into the block, the position order of the transaction is determined. This means there will be no forks in Fabric. Once a transaction is written into a block, it cannot be rewritten later.

We can see that the peer stores the ledger and chain code, and the orderer does not store these at all. When each transaction reaches the orderer, the orderer just mechanically packages the transaction into a block, regardless of the value, amount, etc. of the transaction. This is an important feature of Fabric. All transactions will be sorted out in a strict order, and no transaction will be discarded.

By the end of the second phase, we can understand that the orderer's responsibility is to simply collect transaction update proposals, sort them, package them into blocks, and prepare for distribution.

Process 3 Certification
The last transaction workflow is to distribute and verify blocks from orderer to peer.If the verification is successful, it will be submitted to the ledger.
In particular, in each peer, every transaction in the block is verified before being updated to the ledger to ensure that all transactions are endorsed by the relevant organization. Failed transactions will be retained for future review and will not be updated in the ledger.

In addition to its packaging role in process 2, Orderer is also responsible for distributing blocks to peer nodes in process 3. In this example, O1 distributes blocks to P1 and P2. P1 processes block 2 and then adds block 2 to P1’s ledger L1. At the same time, P2 processes block 2 and then adds block 2 to P2’s ledger L1. Once the operation is completed, the ledger L1 has been updated in both P1 and P2, and each peer can send the processing results to the application connected to them.

The orderer distributes blocks to the peers connected to him is the beginning of process 3. A peer connected to a channel of the orderer node will receive a copy of the new block generated by the orderer. Each peer node processes the received blocks independently, but all peers process blocks in the same way. In this way, ledgers in different peers can reach a consensus. Not all peers must be connected to the orderer node. Blocks can be transferred between peers through the gossip protocol, so that peers can process the same block independently.

After receiving a block, the peer will process the transactions in the order they appear in the block. For each transaction, the peer will check whether the transaction is endorsed by the organization related to it according to the chaincode endorsement policy that generated the transaction. For example, some transactions may require endorsement by only one organization, while other transactions require endorsement by multiple organizations to be valid. This verification process verifies that the results or output produced by all relevant organizations are consistent. Please also note that the third phase of verification is different from the first phase. In this phase, the application only receives the response from the endorsing node and determines whether it needs to send a transaction proposal. If the application sends the wrong transaction and violates the endorsement policy, the peer can still reject the transaction during the third stage of verification.

If the transaction endorsement is correct, the peer will try to submit the transaction to the ledger. In order to be able to write the ledger, the peer must perform a ledger consistency check to ensure that the current ledger status is consistent with the updated ledger status. This state is not always consistent, even if the transaction has full endorsements. For example, another transaction may have already updated the same asset in the ledger, so that the transaction we are updating will never be written to the ledger. In this case, the ledger in each node must maintain consensus through the network, and the verification method of each node is the same.

After the peer verifies each independent transaction, the ledger will be updated. Failed transactions are saved for review. This means that the block in the peer is the same as the block received from the orderer, except for the flag in the block indicating the success or failure of the transaction.

We should also note that the chaincode is not executed in the third phase. This step will only be completed in the first phase, which is important. This means that the chaincode is only available to the endorsing node, not the entire network, which ensures the security and privacy of the chaincode in the endorsing organization. This is different from receiving the execution result of the chain code. The execution result will be shared with all peers in the Channel, regardless of whether they can endorse the transaction. Endorsement nodes are designed in this way to facilitate expansion.

Finally, each time a block is submitted to the peer's ledger, the peer will generate a corresponding event. Block events contain all the contents of the block, while block transaction events only contain brief information, such as whether the transactions in each block are valid. Chaincode events generated by chaincode execution can also be published at this time. Applications can register for these events and receive notifications when these events occur. These notifications are completed during the third and final stage of the transaction workflow.

In general, we can know that the blocks generated by the orderer in the third stage are continuously synchronized to the ledger. The strict ordering of transactions in blocks allows each peer in the blockchain network to consistently verify transactions and submit them to the ledger.

Orderer and Consensus
The entire transaction workflow is called consensus, because all peers agree on the ordering and content of the transaction, and the orderer node coordinates it during the execution process. Consensus is a multi-step process, and the application will only receive notification at the end of the consensus process, but the notification time may be different on different peers.

We will discuss the orderer more later. For now, the orderer is just regarded as the process of collecting and distributing ledger update proposals from the application to the peer, and the peer verifies and updates the ledger.

5. What are the main ways to maintain the security of the public chain?

Public chain: means that anyone in the world can enter the system at any time to read data, send and confirm Blockchain for transaction and competition accounting. For example: Bitcoin, Ethereum.

Private chain: refers to a blockchain whose write permission is controlled by an organization and institution, and the qualifications of participating nodes are strictly restricted.

Consortium chain: refers to a blockchain that is jointly managed by several institutions. Each institution runs one or more nodes, and the data in it is only allowed to be read and written by different institutions in the system. and send transactions, and jointly record transaction data.

Consortium chain is a kind of application of blockchain technology to enterprises.Relatively new approach. Public chains are open to everyone, while private chains usually only provide services for one enterprise. Consortium chains have more restrictions than public chains and usually provide services for collaboration between multiple enterprises.

The difference between the consortium chain and the public chain is that it requires prior permission. Therefore not everyone with an internet connection can access the consortium blockchain. The consortium chain can also be described as semi-decentralized. Control of the consortium chain is not granted to a single entity, but to multiple organizations or individuals.

For consortium chains, the consensus process may be different from public chains. The consensus participants of a consortium chain may be a group of pre-approved nodes on the network, rather than just anyone being able to participate in the process. Consortium chains allow for a greater degree of control over the network.

When it comes to the advantages of the alliance chain:

First of all, the alliance chain is completely controlled by a specific group, but it is not a monopoly. This control can establish its own rules when each member agrees.

Secondly, it has greater privacy, because the information used to verify the block will not be disclosed to the public, and only alliance members can process this information. It creates greater trust and confidence among platform customers.

Finally, compared with public blockchains, consortium chains have no transaction fees and are more flexible. The large number of validators in a public blockchain leads to troubles with synchronization and mutual agreement. Usually this kind of disagreement will lead to a fork, but this will not happen in the alliance chain.

Consortium chain technology can be used to optimize the business processes of most traditional information systems, and is especially suitable for business scenarios without a strong center, multi-party collaboration, and controllable risks. The shared ledger mechanism of the alliance chain can greatly reduce the reconciliation cost in this type of scenario, improve the efficiency of data acquisition, increase fault tolerance, consolidate the foundation of trust, and avoid malicious fraud.

With the continuous development of blockchain technology, more and more institutions and enterprises have begun to increase the research and application of blockchain. Compared with public chains, alliance chains have better implementation and are supported by many enterprises and governments.

Consortium chain can be understood as a distributed ledger established by internal organizations to meet the needs of specific industries. This ledger is open and transparent to internal organizations, but if there are relevant business needs to modify the data in the ledger, smart contracts still need to be added.

Smart contract is a computer protocol designed to spread, verify or execute contracts in an information-based manner. Smart contracts allow trusted transactions to be made without third parties, which are traceable and irreversible.

In general, the current mainstream architecture of alliance chain smart contracts is: system contract + business contract.

System contract: configured before node startupCompleted, generally used for system management (such as BCOS pre-compiled contracts (authority management, naming management, etc.)), written by the project party, with high security.

Business contract: written based on actual business , needs to be deployed, similar to public chain smart contracts, written by general internal institutional participants, needs to comply with certain requirements, and has average security.

Compared with conventional public chains, alliance chain contracts are standardized, and Security has been improved to a certain extent, but security risks may still exist in the following aspects:

(1) Code language security features

1 One is to continue to use the mainstream public chain programming language and improve on it (such as solidity used by BCOS), and the other is to use a general programming language as the basis and specify the corresponding smart contract module (such as fabric's Go/ Java/Node.js), no matter what language is used to program smart contracts, there are security issues related to the corresponding language and related contract standards.

(2). Problems caused by contract execution Security issues

Integer overflow: No matter what virtual machine is used to execute the contract, various integer types have corresponding storage widths. When trying to save data exceeding this range, signed numbers will Integer overflow will occur.

Stack overflow: When too many method parameters and local variables are defined, and the bytes are too large, program errors may occur.

Denial of Service Attack: Main It involves an alliance chain that consumes resources to execute the contract, and the corresponding transaction cannot be completed due to exhaustion of resources.

(3) Contract security issues caused by the system mechanism

This mainly refers to the alliance chain with multi-chain architecture:

If the generation of contract variables depends on uncertain factors (such as the timestamp of this node) or a variable that is not persisted in the ledger, Then the transaction verification may not pass because the read and write sets of the variable in each node are different.

Global variables are not saved in the database, but are stored in a single node. Therefore, if this When a node fails or restarts, it may cause the global variable value to no longer be consistent with other nodes, affecting node transactions. Therefore, data read from, written to, or returned from the contract should not rely on global state variables.< br />
When calling a contract on an external chain under a multi-chain structure, you may only get the return result of the called chain code function, without any form of transaction submission on the external channel.

When a contract accesses external resources, it may expose security risks that are not expected by the contract and affect the chaincode business logic.

(4), business security issues

Alliance The smart contract of the chain is executed to complete a certain business requirement.Therefore, there may still be security risks in business logic and business implementation, such as mismatched function permissions, unreasonable input parameters, and inadequate exception handling.

Our suggestions for alliance chain security:

(1) Simplify the design of smart contracts to achieve a balance between functionality and security

( 2) Strictly implement smart contract code audit (self-evaluation/project team review/three-party audit)

(3) Strengthen security training for smart contract developers

( 4) In the implementation of blockchain applications, it needs to be gradually promoted, from simple to complex, and in the process, the functions/security attributes related to contracts and platforms are constantly sorted out

(5) Consider DevSecOps (Development +Security+Operations) idea

Chain platform security includes: transaction security, consensus security, account security, compliance, RPC security, endpoint security, P2P security, etc.

The methods used by hackers to attack the alliance chain include: internal threats, DNS attacks, MSP attacks, 51% attacks, etc.

Take MSP attack as an example: MSP is the abbreviation of Membership Service Provider in the Fabric alliance chain. It is a component that provides an abstract member operation framework. MSP will issue and verify Certificates, as well as all cryptographic mechanisms and protocols behind user authentication are abstracted. An MSP can define its own identity, as well as identity management (authentication) and authentication (generating and verifying signatures) rules.

In general, attacks against MSP may include the following aspects:

(1) Internal threats: a) The current version of MSP allows single certificate control, In other words, if an insider holds a certificate that can manage the MSP, he will be able to configure the Fabric network, such as adding or revoking access rights, adding identities to the CRL (essentially blacklisting identities), Overly centralized management may lead to security risks. b) If there are IoT devices such as sensors connected to the alliance chain, they may spread false information to the chain, and because the sensors themselves may not support complete security protection, it may lead to further attacks.

(2) Private key leakage. The certificate files of nodes or sensors are generally stored locally, which may lead to private key leakage, which may lead to Sybil attacks and Man-in-the-Cloud attacks. ), etc.

(3) DNS attack: When a new participant's identity is created and added to the MSP, a DNS attack may occur under any circumstances. To create blockchain membersThe process of creating a certificate can cause attacks in many places, such as man-in-the-middle attacks, cache poisoning, and DDOS. Attackers can convert simple DNS queries into larger payloads, causing DDoS attacks. Similar to CA attacks, this attack results in certificate tampering and/or theft, such as the permissions and access certain blockchain members will have. Sensor networks are particularly vulnerable to DDOS attacks. Smart cities face the challenge not only of implementing sensor networks that are vulnerable to DDOS attacks, but also of the accompanying blockchain systems.

(4) CA attack: Digital certificates and identities are crucial to the operation of MSP. Hyperledger Fabric allows users to choose how to run certificate authorities and generate cryptographic materials. Options include Fabric CA, processes built by contributors to Hyperledger Fabric, Cryptogen, and own/third-party CAs. The implementation of these CAs themselves has its own flaws. Cryptogen generates all private keys in a centralized location, which are then copied securely by the user to the appropriate hosts and containers. By providing all private keys in one place, this facilitates private key compromise attacks. Implementation weaknesses aside, the entirety of the MSP, and therefore the membership of the blockchain, runs on a CA and has the ability to trust that the certificate is valid and that the owner of the certificate is who they say they are. An attack on a well-known third-party CA, if successfully executed, could compromise an MSP's security, leading to fake identities. Another weakness of CAs in Hyperledger Fabric is the way they are implemented in MSP. MSP requires at least one root CA and can support as root and intermediate CAs as needed. If the root CA certificate is attacked, it will affect all certificates issued by the root certificate.

Chengdu Lian'an has launched a consortium chain security solution. With the development of the consortium chain ecology, in 2020 Chengdu Lian'an has cooperated with the Cyberspace Administration of many provinces to provide consortium chain systems for local governments, enterprises and institutions. A multi-level security audit was conducted from the bottom of the chain to the application layer, and the loopholes and vulnerabilities of the multi-scenario, multi-application and multi-form alliance chain system and its supporting systems were discovered.

In addition, Chengdu Lian'an has cooperated with Ant Blockchain. As the first batch of nodes selected by Ant Blockchain to join the open alliance chain, we will give full play to our security technology, service and market advantages, and cooperate with Ant Blockchain. The open alliance chain jointly expands the market, builds the ecology, and protects the safety of the ecology.

On the one hand, our smart contract formal verification product VaaS will continue to provide "military-level" security testing services for open consortium chain applications, conduct security testing for applications before they go online, and prevent security incidents. Logical error; our "Eagle Eye" security situation awareness system uses AI + big data technology to provide a comprehensive and timely "security + operation" situation for the open alliance chain and its applications.Perception, on-chain contract risk monitoring, security warning, alarm, firewall blocking and real-time response processing capabilities.

On the other hand, our security products have accumulated hundreds of thousands of customer groups. We will leverage our global customer resources and market advantages to expand the market with the open alliance chain.

On the alliance chain platform, we can provide an overall security solution for the entire life cycle. Chengdu Lianan uses the four major technologies of network security, formal verification, artificial intelligence and big data analysis as the core to create Established the "Beosin one-stop blockchain security service platform" for the security of the entire blockchain ecosystem.

"Beosin one-stop blockchain security service platform" includes four core security products and eight star security services, providing blockchain companies with security audits, virtual asset tracing and AML anti-money laundering, security Comprehensive security services and support such as protection, threat intelligence, security consulting and emergency response, to achieve a full life cycle security solution for the blockchain system "R&D → Operation → Supervision".

We will actively leverage the advantages of leading blockchain security companies, jointly build a secure blockchain business network, promote the healthy and safe development of the blockchain industry, and explore the infinite possibilities of the future of blockchain. .

6. What exactly is a blockchain fork?

Fork is a magical term in the blockchain world. The blockchain network has since been divided into two, and people with different consensuses have parted ways. Is this a turbulent split or the formation of a new consensus?

The fork of the blockchain can be said to be a unique version upgrade method in the blockchain network. Just like the Internet software we use in our lives, after using it for a period of time, it will naturally It needs to be optimized and upgraded to solve some users' usage problems. The same is true for the blockchain, except that its upgrade is special. The upgrade will be jointly decided by the participating miners, and it can even produce multiple versions. It is not like the Internet where there is a dictatorship and no choice.

The principle is this, because the blockchain is a chain structure composed of data blocks. Therefore, when he wants to upgrade, he will actually start from a certain data block and connect to two different data blocks, thus dividing into two chains; just like branches, everyone shares the same trunk, and the sharing will be separated. The previous data, but there are many branches belonging to multiple chains, and this process is called bifurcation.

We have also said before that the upgrade of the blockchain is decided by the miners together. Since there are more people participating, there will be different opinions. When everyone can reach a consensus, the points will be divided. The two forked chains are equivalent to one being an old version and the other being a new version, both of which are compatible. After the miners on the old chain are upgraded, they gradually transition to the new chain. In the end, everyone is upgraded and only the new chain is left. This is called soft chain. Forks. Specifically, soft forks are temporary phenomena within the system.It will not fork a new blockchain. When the blockchain system is upgraded, some nodes can still work even if they are not upgraded in time. After the soft fork of Bitcoin, it will not produce two chains like a hard fork, but will remain on one chain. The soft fork will undergo some upgrades, but it will not affect the stability and effectiveness of the entire system. The old The node will be compatible with the new node, but the new node is not compatible with the old node. The two can still coexist on the same chain.

When the miners cannot reach a consensus, although everyone shares the previous data, two new chains are formed, just like the evolution of species. Some monkeys evolved into humans, and the other evolved into With the orangutan, both species have changed and are incompatible with each other. This is called a hard fork. That is to say, a permanent divergence occurs in the blockchain. After the new consensus rules are released, some nodes that have not been upgraded cannot verify the blocks produced by the upgraded nodes, and a hard fork usually occurs. A hard fork in the code will change the difficulty level of the algorithm.

The substantial bifurcation occurred because of the irreconcilable differences in the original community's internal ideas during the dynamic development of the project. As a decentralized organization, the community behind the blockchain advocates the free association of non-violent free people, which means that in the process of moving towards the unknown future, when new problems encountered exceed the original established rules of the game, Once disagreements arise, it will be difficult to reach agreement. This is determined by the decentralized nature of the blockchain gene.

The development of blockchain technology is still in its early stages. For blockchain, bifurcation is equivalent to a process of technological iteration. As people continue to discover that blockchain technology has Limitations, only by continuously upgrading and expanding this technology can blockchain technology mature. Of course, this kind of fork runs counter to the non-tamperable nature of blockchain, but no technology is inherently perfect, and blockchain is no exception. If the development of technology is uncontrollable when errors occur, then this technology cannot be used. Even universally, people's trust in it cannot be improved. And the result of the fork is decided by voting by community members, which still adheres to the principle of decentralization to a certain extent.

People have different opinions on blockchain forks, but in the historical process of blockchain development, forks have undoubtedly made blockchain more story-telling and possible. In general, the upgrade method of forking is a lot of trouble. However, he gave everyone more choices. Perhaps, blockchain will conceive more possibilities in this kind of seeking common ground while reserving differences.