Ensuring Data Integrity for Consumer-Centric Digital Twins in Healthcare 5.0 via a Blockchain-Oriented Signature

With the rapid development of consumer electronics and the healthcare sector, Healthcare 5.0 has emerged, integrating multiple advanced information technologies to create human-centered systemic healthcare services. Among these technologies, consumer-centric digital twins (CCDTs) provide patients with virtual models, enhancing medical risk management and health guidance, while simultaneously imposing higher requirements on data security and service efficiency. Blockchain addresses this by providing a secure, decentralized framework that eliminates trusted intermediaries. Within this framework, distributed signatures can enable consensus for collaborative multi-party processes to ensure the integrity of medical data, thereby providing a reliable data source for CCDTs in Healthcare 5.0 to a certain extent. However, existing distributed signatures for healthcare systems still struggle with low efficiency and exfiltration attacks. This is due to the unique demands of data-sensitive medical consumer electronics, which necessitate high efficiency to meet strict medical timeliness. To address these challenges, this paper proposes a non-interactive identity-based threshold signature scheme with cryptographic reverse firewalls (CRFs) for CCDTs in Healthcare 5.0 (NI-IBTS-CRF). The scheme eliminates reliance on public key infrastructure via identity-based cryptography and adopts a non-interactive signing paradigm to achieve higher signing efficiency and reduce energy consumption for medical devices. Additionally, the scheme incorporates efficient CRFs that enable fast rerandomization to mitigate exfiltration attacks inherent in existing solutions. Experimental results demonstrate that the CRFs introduce only around 10% additional overhead, while NI-IBTS-CRF still achieves leading signing efficiency compared to existing schemes, thus providing a secure and signing-efficient approach to safeguarding data integrity for CCDTs in Healthcare 5.0.