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@article{207395,
        author = {Shubhangi Santosh Kekate and Dr. Syed Sumera Ali and A. T. Jadhav and Dr. D. L. Bhuyar and Dr. G. B. Dongre},
        title = {Privacy-Preserving Blockchain Architectures for Central Bank Digital Currency Systems},
        journal = {International Journal of Innovative Research in Technology},
        year = {2026},
        volume = {13},
        number = {3},
        pages = {742-750},
        issn = {2349-6002},
        url = {https://ijirt.org/article?manuscript=207395},
        abstract = {Critical issues with user privacy, transaction security, and regulatory compliance have emerged due to the rapid growth of digital financial systems and the introduction of Central Bank Digital Currencies (CBDCs). Although blockchain technology supports decentralization and transparency, it often conflicts with the strict privacy requirements of financial systems. This study presents a detailed analysis of privacy-preserving blockchain architectures for CBDC systems, focusing on techniques such as zero-knowledge proofs, secure multi-party computation, and advanced consensus mechanisms. In addition to theoretical analysis, this work also includes the design and implementation of a Java-based custom blockchain system, where experimental evaluation is performed on transaction processing and security parameters. The results demonstrate improvements in privacy protection, reduced latency, and better throughput using a permissioned blockchain approach. The study evaluates existing approaches in terms of performance, scalability, and privacy, highlighting that while many architectures enhance transaction privacy, they often introduce trade-offs such as increased computational complexity and reduced scalability. Furthermore, the lack of standardization and challenges in meeting regulatory requirements like auditability and traceability remain significant concerns. To address these limitations, this research proposes a CBDC based on a Proof-by-Approval consensus mechanism, extending Proof-of-Reputation to improve trust, security, and decentralization. A prototype privacy-preserving blockchain architecture was implemented using Java and evaluated on simulated CBDC transactions. The proposed approach achieved an accuracy of 97.2% while improving transaction privacy and reducing processing delay compared to existing approaches.},
        keywords = {Privacy-Preserving, Decentralized Platform, Banking Transactions, Blockchain Technology, Unspent Transaction Outputs (UTXOs), Data Security, Cryptographic Techniques, Financial Institutions, Transaction Transparency, Digital Banking Solutions, etc.},
        month = {August},
        }