近年來，隨著比特幣的出現與大量應用，加密貨幣成為熱門討論議題，而其核心之區塊鏈(Blockchain)技術也迅速被產業界所關注。區塊鏈技術具備去中心化、安全及公開透明等特性，現有應用大多為透過區塊鏈技術提升產業價值或是服務品質，其中以金融服務為目前區塊鏈技術最為頻繁的應用領域之一。現今區塊鏈應用大多透過以太坊(Ethereum)平台進行應用開發，然而，隨著使用者的大量增加，用戶端運算負擔將大量提升，進而影響系統營運效率。鑒於此，本研究提出一套輕量化區塊驗證流程，主要為在私有鏈的環境下，透過縮減區塊數量，並結合RSA環狀簽章和雜湊函數SHA-256等運算作為區塊鏈鏈結技術，讓使用戶端能降低運算負擔，提高系統營運效率。

The invention of Bitcoin and the booming application of Bitcoin in recent years, push cryptocurrency to its top. Blockchain, the core technology of Bitcoin, has picked up the attention of industry and rapidly adopted by firms. Nowadays, blockchain is adopted by most businesses for increasing their industry value and improving their service quality. Since blockchain has features of decentralization, secure and transparent, the technology mostly applied to financial firms. However, the increasing amount of users creates more blocks, which means the computing burden on clients. This issue can decrease performance and efficiency in firms or organization that adopted the technology or ran the system. Therefore, we proposed a lightweight block verification process in this research. By adopting private chain rather than public chain, the blocks can be reduced. With a private chain applied RSA ring signature and SHA-256 as linking technique, the computing burdens can be reduced and improve the operation efficiency.

摘要 I
Abstract III
目錄 V
圖目錄 VII
表目錄 IX
壹、緒論 1
一、研究背景與動機 1
二、研究目的與問題 3
三、論文架構 4
貳、文獻探討 5
一、比特幣（Bitcoin） 5
二、區塊鏈（BlockChain） 7
三、以太坊（Ethereum） 11
四、智慧合約（Smart Contract） 12
五、環狀簽章（Ring Signature） 13
參、系統研究架構 15
一、前言 15
二、系統描述 15
三、系統目的 17
四、系統執行方式 18
五、應用情境：智慧保單 23
肆、系統效能分析 29
伍、結論 35
參考文獻 37

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