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@article{203935,
        author = {Siddhant Gath and Milind Rane},
        title = {ZK-MEDSHARD: Enhancing Data Security In Healthcare Using Blockchain},
        journal = {International Journal of Innovative Research in Technology},
        year = {2026},
        volume = {13},
        number = {1},
        pages = {413-418},
        issn = {2349-6002},
        url = {https://ijirt.org/article?manuscript=203935},
        abstract = {ZKMedShard is a decentralized, privacy-preserving healthcare data sharing architecture that combines blockchain, sharded off-chain storage, and zero-knowledge proof–based access control to address long-standing challenges in electronic health record (EHR) interoperability, security, and regulatory compliance. The system stores large, encrypted medical records in sharded form across off-chain storage providers, while maintaining integrity-critical metadata, consent policies, and immutable audit logs on a permissioned blockchain via smart contracts. Patients and healthcare providers interact through a web-based frontend and a modular backend that orchestrates record encryption, sharding, and retrieval, as well as zk-SNARK generation for authorization proofs. During record registration, the platform encrypts and shards medical data, uploads shards to off-chain storage, and anchors shard descriptors and access-control rules on-chain, thereby enabling tamper-evident and traceable registration of clinical encounters. During access requests, authorized entities submit zero-knowledge proofs that demonstrate compliance with patient consent and policy constraints without revealing underlying identities or cryptographic secrets, after which the smart contract verifies proofs and conditionally releases shard descriptors for secure reconstruction and decryption. This hybrid design improves confidentiality by keeping protected health information off-chain, enhances integrity and non-repudiation through blockchain-based logging, and supports scalable healthcare data interoperability through sharding and off-chain storage, aligning with current directions in blockchain-enabled, patient-centric healthcare systems.},
        keywords = {Blockchain, electronic health records, healthcare data sharing, medical privacy, off-chain storage, sharding, smart contracts, zero-knowledge proofs},
        month = {June},
        }