P2Q-ASB: PUF-Secured Post Quantum Aggregate Signature Scheme using Public Blockchain for e-Healthcare Systems

The convergence of diverse wireless technologies inside a unified e-healthcare platform has opened up several vulnerabilities to cyber threats. To assure data integrity and reduce system overhead, aggregate signature methods provide a convenient way to combine multiple message signatures into a single compact signature. However, classical aggregate signature schemes are vulnerable to quantum threats and device impersonation attacks. To mitigate the research gap, in this paper, we leverage the benefits of Physical Unclonable Function (PUF) and public blockchain to propose a quantum-safe latticebased aggregate signature scheme (P2Q-ABS). The security of P2Q-ASB is based on the difficulty of the Ring Learning-withError (Ring-LWE) problem. The proposed P2Q-ASB scheme is a unified approach that protects IoMT devices with PUFs, provides quantum-resistant aggregate signatures, and stores electronic medical records in a blockchain-based distributed ledger. We provide a testbed implementation of lattice-based signatures for single and group messages. Moreover, we show the blockchain simulation results for various blocks mined and transactions per block. Security and performance analysis shows that P2Q-ASB offers enhanced security measures and facilitates more efficiency when compared to current state-of-the-art methodologies.