Hyperledger Fabric Runtime Transaction Processing Flow

Hyperledger Fabric is a modular and extensible blockchain implementation that offers a flexible architecture for enterprise-grade blockchain solutions. In this article, we will explore the runtime transaction processing flow of Hyperledger Fabric, which is a key aspect of its design.

Transaction Proposal

The first step in the Hyperledger Fabric transaction processing flow is the submission of a transaction proposal by an application SDK. The SDK receives a response back, which includes the ReadWrite set post-endorsement. This ReadWrite set represents the proposed changes to the ledger that the transaction would make.

Transaction Endorsement

Once the transaction proposal is received, it is sent to the counter-parties represented by endorsing peers on their channel. Each peer executes the transaction by calling the specified chaincode function and signs the result, which becomes the ReadWrite set of the transaction. Endorsing peers may participate in multiple channels, allowing concurrent execution.

Transaction Submitted to Ordering Service

After the transaction has been endorsed by the participating peers, it is submitted to the ordering service. The ordering service accepts endorsed transactions and orders them according to the plug-in consensus algorithm. Once the transactions are ordered, the ordering service delivers them on the channel to the peers.

Transaction Validation

The final step in the Hyperledger Fabric transaction processing flow is transaction validation. Peers on the channel receive transactions and validate them before committing to the ledger. The validation process includes the following steps:

1. Validates each transaction and commit block
2. Validates the endorsement policy
3. Validates ReadSet versions in state DB
4. Commits the block to blockchain
5. Commits the valid transaction to state DB

Conclusion

The Hyperledger Fabric runtime transaction processing flow is a critical component of its design. Its modular and extensible architecture enables flexible and secure enterprise blockchain solutions. By understanding the transaction processing flow, organizations can make better technology and solution design decisions, especially around scalability, security, and performance.