Design and Implementation of a Blockchain-Based Personal Financial Recording System Using Proof of Authority (PoA) Consensus

Abstract

This research aims to develop a secure, transparent, and tamper-proof personal financial recording system by utilizing blockchain technology with the Proof of Authority (PoA) consensus mechanism. Many conventional recording methods are vulnerable to manipulation and data loss, which highlights the need for a more robust digital solution. The system is developed using the Flask framework (Python) and applies RSA digital signatures to verify transaction authenticity. The Research and Development (R&D) method is used, encompassing system analysis, design, implementation, and testing. Transactions are stored in JSON files and validated by registered validators. The system ensures that only authorized parties can approve and sign transactions. The testing phase showed that hash validation and signature verification mechanisms worked effectively, ensuring data integrity. Although the system successfully detected manual manipulations of block data, it requires better user feedback when validation fails. The study concludes that a PoA-based blockchain system is highly suitable for individual financial recording needs, combining cryptographic security and ease of use.

Keywords: Blockchain; Proof of Authority; Personal Finance; Digital Signature; Flask

INTISARI

Penelitian ini bertujuan untuk mengembangkan sistem pencatatan keuangan pribadi yang aman, transparan, dan tidak dapat dimanipulasi dengan memanfaatkan teknologi blockchain dan mekanisme konsensus Proof of Authority (PoA). Sistem pencatatan konvensional sering kali rawan manipulasi serta kehilangan histori transaksi, sehingga diperlukan solusi digital yang lebih andal. Sistem dikembangkan menggunakan framework Flask (Python) dan menerapkan tanda tangan digital RSA untuk menjamin keaslian data transaksi. Metode penelitian yang digunakan adalah Research and Development (R&D), meliputi analisis, perancangan, implementasi, dan pengujian sistem. Transaksi disimpan dalam file JSON dan divalidasi oleh validator yang terdaftar. Sistem memastikan hanya pihak yang memiliki otoritas yang dapat menyetujui dan menandatangani transaksi. Hasil pengujian menunjukkan bahwa sistem berhasil mendeteksi perubahan data secara manual melalui validasi hash dan verifikasi tanda tangan digital. Meski demikian, sistem perlu ditingkatkan dalam aspek umpan balik kepada pengguna saat validasi gagal. Kesimpulannya, sistem blockchain berbasis PoA sangat cocok untuk pencatatan keuangan pribadi karena menggabungkan keamanan kriptografis dengan kemudahan penggunaan.

Kata Kunci: Blockchain; Proof of Authority; Keuangan Pribadi; Tanda Tangan Digital; Flask