zk-ID: A privacy-preserving identity verification framework for healthcare using blockchain, ECDSA, and zero-knowledge proofs

Abstract

Everything is becoming digital these days, health records are no exception. Digitization of healthcare sector would make the outcome improved such as enhanced patient care, but like every digitization, this has also introduced significant privacy and security concerns such as health data breaches. This paper proposes a “Health-ID Verification Framework” that combines blockchain, ECDSA and ZKPs to enable secure, GDPR-compliant health id verification. zk-ID leverages zk-SNARKS for privacy preservation, chameleon hashes are used for retroactive redaction that is in line with GDPR’s “right to be forgotten” clause. Sharded Blockchain networks achieve about 1,200 TPS. Evaluations show zk-ID reduces verification latency by 62% compared to Sovrin and lowers storage costs to 21.67/record via hybrid on/off-chain architectures. Interoperability is achieved through FHIR/HL7 APIs while eliminating fraud through multi-authority attribute-based encryption (MA-ABE).