Secure and Efficient Lattice-based Signcryption for Blockchain-Enabled IoT Healthcare

The integration of Internet of Things (IoT) technologies into modern healthcare systems has significantly enhanced patient care and real-time monitoring. However, this advancement introduces serious security and privacy concerns, such as data breaches, unauthorized access, and identity leakage, which are especially critical in healthcare environments. These threats are further intensified by the emergence of quantum computing, rendering traditional cryptographic schemes increasingly vulnerable. To address these challenges, we propose secure and efficient lattice-based signcryption for blockchain-enabled IoT healthcare (SELSBH ). The scheme leverages the quantum-resistant hardness of the Learning With Errors (LWE) problem to ensure strong confidentiality, authentication, and data integrity. It also supports user anonymity and unlinkability on the blockchain, while maintaining lightweight operations suitable for resource-constrained IoT devices. The security of SELSBH is formally validated using the Scyther tool and the Random Oracle Model (ROM), demonstrating its resilience against both classical and quantum adversaries. Additionally, we conduct a comprehensive performance evaluation by comparing SELSBH with existing protocols in terms of security features, communication cost, and computational efficiency. The results highlight the advantages of SELSBH in achieving a robust, privacy-preserving, and quantum-secure solution for next-generation e-healthcare systems.