Blockchain and SC-PBFT Enabled Traceability Method for Vaccine Supply Chain

The demand for vaccines is rising due to increased public health awareness and advances in biotechnology, but since most vaccine traceability systems are centralized, there are still issues with data integrity, security, and authenticity in the vaccine supply chain. This paper proposes a method for vaccine supply chain traceability based on the distributed and traceable characteristics of blockchain, along with IoT edge devices and cloud service technology, in order to realize decentralized, transparent, safe, and efficient vaccine information traceability. Blockchain ensures the authenticity, transparency, and traceability of data. The structure of the cloud-edge combination improves the efficiency and stability of the traceability platform. However, the Practical Byzantine Fault Tolerance (PBFT) mechanism has the issue of performance degradation when the number of nodes is high; consequently, we proposed Practical Byzantine Fault Tolerance for Supply Chain (SC- PBFT) to make it adapt to vaccine supply chain scenarios that have a large number of nodes. SC-PBFT elects the master node through a reasonable rating system. Meanwhile, the data synchronization verification mechanism has been added. The experimental findings demonstrate that the SC-PBFT algorithm can significantly lower consensus latency and increase Transaction Per Second (TPS). The proposed traceability method fixes the issues with the current centralized traceability system's insufficient data and easy forgery. The consensus efficiency of the data and the method's feasibility are both enhanced by the SC-PBFT.