Abstract:
Blockchain technology has ushered in transformative possibilities within the healthcare sector by creating a unified
distributed network that streamlines the exchange of patient data among various stakeholders. However, the adoption of private or
consortium-based blockchain models has raised concerns about the potential isolation and fragmentation of these networks. To address
this challenge, blockchain interoperability has emerged as an escalating research area that offers a means for independent blockchains
to collaborate across diverse platforms within a federated ecosystem. This study proposed a novel cross-chain communication protocol
designed to integrate independent blockchains operating on different platforms. By leveraging a global smart contract triggering
mechanism, this protocol establishes a standardized transaction conversion module to ensure transaction compatibility across various
blockchain platforms within a federated network. The practical implementation of our cross-chain communication protocol was
demonstrated through the exchange of electronic health records between the Hyperledger Fabric and Ethereum networks. Extensive
experimentation was conducted to assess the performance metrics, revealing critical dependencies between the source and target
blockchain networks in terms of the average elapsed time and query processing duration within the target network. The findings of this
study underscore the considerable potential of blockchain interoperability within a federation, particularly when applied to the sharing
of patient EHRs dispersed across multiple autonomous blockchains.