Citation :

Shalini Kumaravel, Afrina Bhanu, 2025. "Blockchain-Based Privacy Preservation in Digital Identity Systems" International Journal of Computer Science & Information Technology  Volume 1, Issue 2: 34-42.

Abstract :

As we witness digital identity systems making its entry into the government and private sector realm, protecting personal privacy and providing secure data becomes a necessary evil. Centralised Identity: They produce hazards being breaches, tracking and identity theft. In summary, blockchain provides a decentralized way with a higher degree of transparency and auditability but must be supplemented by privacy-preservation techniques to meet current and future data protection needs. More specially, although BoL is the abstract interface of BoD and it dependents on the lower-level storage. (A) Whenb is allowed to look at an arbitrary MapType. In this article we compile the blockchain digital identity frame works and discuss ways to maintain privacy. This report offers a comparison between models used in the industry, and introduces new best practices (DIDs / VCs) as well as cryptographic tools such as ZKPs, ring signatures, homomorphic encryption etc. In this paper, we present a hybrid model combining on-chain verification with off-chain document storing to resolve the trade-off between scalability, privacy and interoperability. The ultimate portion of the paper concludes with a reflection on existing deployments, legal requirements and the future roadmap of private blockchain identity systems.

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Keywords :

Blockchain, Self Sovereign Identity, Privacy Preserving, Zero-Knowledge Proofs, Dids And Vcs, GDPR.