基於多重加密與權限管理之隱私保護區塊鏈系統與應用設計

Abstract

有鑑於近期加密貨幣火熱的發展及迅速的增值，比特幣背後的區塊鏈開始被大家所探討和應用，區塊鏈技術由密碼學、數學、演算法、共識機制及經濟學所組成，結合點對點的網路通訊（P2P），打造出一個去中心化的交易平台，本系統以比特幣原始碼為基礎，且不同於以往去中心化的原生型區塊鏈，本研究將著重在為企業或聯盟提供的弱中心化區塊鏈，在許可制架構下，加入權限管理、多通道設計、時效性設計、多重加密及混合式區塊鏈設計，提供企業級運用的區塊鏈解決方案，並藉由競標系統的實作，展示在競標管理、競標價格、結標流程、身份管理及業務隔離的情境下結合區塊鏈之運用，期望透過本研究之貢獻，當一個區塊鏈改進設計的先驅者，提供未來區塊鏈商業級應用的參考模型，進而達到本研究改進區塊鏈設計之目的。

With the rapid growth of cryptocurrency recently, the blockchain technique behind Bitcoin has been widely discussed and utilized. As a decentralized peer-to-peer (P2P) trading platform, Blockchain technique is composed of the cryptography, mathematics, algorithms, consensus mechanism, and economics. This research develops a privacy preserving blockchain system based on Bitcoin source codes. We emphasized on a weakly centralized blockchain design for the enterprise or business alliance with multiple encryption and authority management attributes. In addition, multi-channel, timeliness design, and hybrid chain are also developed in the proposed blockchain system. In order to demonstrate the practicality of our novel system design, a bidding system on our blockchain is implemented as the case study. It shows the real demonstration of bid management, bid price, closing process, identity management and business isolation. The contribution of this thesis is to improve the original blockchain system design to realize some future business applications, and to develop a privacy-preserving blockchain system based on multiple encryption and authority management.