Blockchain to provide mutable transactions

Blockchain mutable transaction method:

Method overview: The document proposes a method to operate the blockchain to provide mutable transactions, which solves the limitation of the immutability of traditional blockchain.

Transaction information structure: The blockchain consists of a series of blocks, each of which contains transaction information and block headers. Transaction information can include transactions and their mutability policies.

Mutability policy: The mutability policy defines the conditions for changing transactions, such as the changing party, time window, etc.

Transaction change process:

Sending mutable transactions: The sending entity provides mutable transaction information including transactions and mutability policies, which are verified and added to the new block by the verification entity.

Change request: The change entity (mutator) provides change information, including the reference of the transaction to be changed and the new transaction, and replaces the original transaction after verification.

Activate new transaction: After successful verification, the new transaction replaces the original transaction and is set as the active transaction to provide the latest information.

Application scenarios and cases:

DAO smart contract vulnerability repair: Through mutable transactions, DAO smart contracts can repair vulnerabilities without hard forks, maintaining the integrity and trust of the blockchain.

Distributed timestamp service and file storage: application scenarios of blockchain technology, emphasizing the importance of decentralization and trustless third parties.

Negative account balance problem solution: Solve the negative account balance problem that may be caused by variable transactions by recursively canceling transactions with insufficient funds.

Technical implementation details:

Merkle tree structure: used to verify the integrity of transaction data in the blockchain.

Encryption and decryption: Use AES to encrypt transaction information to ensure that only authorized entities can access specific historical versions of data.

Time window and policy execution: Time window limits the variability period of transactions, and policy execution ensures that transaction changes meet predetermined conditions.

Blockchain architecture and components:

Blockchain architecture: describes the general architecture of blockchain, including components such as blocks, transactions, and smart contracts.

Verification entities and miners: responsible for verifying transactions and creating new blocks, maintaining the integrity and security of the blockchain.

Consensus protocol: Manage the blockchain through the consensus protocol to ensure that nodes in the network reach consensus.

Specific implementation and extension:

Hyperledger Fabric extension: Implement the functions of variable transactions and mutation transactions by modifying the code of Hyperledger Fabric.

Recommendation system case: Use blockchain technology to build a fair and transparent recommendation system, and implement content review and scoring through smart contracts.

Advantages and challenges:

Advantages: Provide variability of blockchain data, fix vulnerabilities without hard forks, and enhance the flexibility and practicality of blockchain applications.

Challenges: Ensure the security, transparency and traceability of transaction changes, and avoid potential security vulnerabilities and trust issues.

Short answer questions:

What is the main innovation of blockchain technology proposed in the document?

The main innovation of blockchain technology proposed in the document is to introduce the concept of mutable transactions, which allows transaction records on the blockchain to be modified under certain conditions, thereby overcoming the limitations of the immutability of traditional blockchains.

What are the key elements of the variability strategy?

The key elements of the variability strategy include: the entity that changes the transaction (such as the sender, receiver or other designated change party), the time window for the change operation (that is, how long the transaction is mutable), and possible other conditions (such as the triggering of specific events).

Briefly describe the change process of mutable transactions in the blockchain.

The change process of a mutable transaction includes: first, the sending entity provides mutable transaction information including the transaction and mutability policy; second, the verifying entity verifies the information and adds it to the new block; then, the changing entity provides the change information, and replaces the original transaction after verification; finally, the new transaction is set as the active transaction and provides the latest information.

Why do we need to solve the negative account balance problem? What solution does the document propose?

In a mutable transaction, if a transaction is modified to reduce the transfer amount, and other transactions it depends on have been executed, it may cause a negative account balance problem. The solution proposed in the document is to recursively cancel those transactions that cause negative balances, ensuring that all transactions remain valid and account balances are non-negative.

How can Hyperledger Fabric be extended to support mutable transactions?

Hyperledger Fabric introduces the data structure and processing logic of mutable transactions and mutant transactions by modifying its code base. Specific extensions include defining new transaction types, modifying the consensus protocol processing flow, and adding management functions for active transaction status.

In what practical application scenarios does the blockchain technology proposed in the document have potential?

The blockchain technology proposed in the document has potential in multiple practical application scenarios, including but not limited to: instant repair of smart contract vulnerabilities (without hard forks), distributed timestamp services, file storage solutions, and building fair and transparent recommendation systems, etc. These application scenarios all benefit from the variability and enhanced flexibility of blockchain data.