基於區塊鏈的名譽系統之設計與實現

The Design and Implementation of Reputation Systems for Blockchain

王品閎(Pin-Hong Wang)

指導教授 ： 曹承礎

共同指導教授 ： 蔡益坤

國立臺灣大學/管理學院/資訊管理學研究所/碩士(2019年)

https://doi.org/10.6342/NTU201901483

摘要

名譽對於人以及企業佔有非常重要的地位。擁有一個良好的名譽能提供給企業更高的收入、更好的商業關係以及更多的潛在機會。根據2016年的調查顯示，74%的潛在客戶表示，當他們看到正面評價時，會對於該企業具有更高的信任感。而在現今網路發達的時代，名譽系統的應用無處不在。如何建置一個具有高信任感，並且阻擋各種攻擊危機，將會是現今名譽系統所面臨的重要問題。
隨著區塊鏈科技的興起，許多人開始探討是否能將區塊鏈與名譽系統作進一步的結合，以達到互利互惠的效果。本研究目的乃對於名譽系統以及區塊鏈科技為討論主軸，仔細評估兩者分別優缺點，希望能藉由區塊鏈科技的名譽系統，不但能解決名譽系統所遭遇到的困境、更可以改善現有區塊鏈科技對於鏈外交易無法評估的缺陷。本篇研究使用以太坊（Ethereum）搭配智能合約（Smart Contract）的建置，實際實作出一套結合區塊鏈科技的名譽系統，提供給未來企業進行導入時參考。
實驗結果顯示，第一、對名譽系統來說，使用區塊鏈科技能有效提升其信任感，並且能有效阻擋目前所遭遇之攻擊。第二、對區塊鏈科技來說，於其基礎建置名譽系統能有效改善區塊鏈本身對於鏈外活動追蹤不易之困境。第三、對企業來說，使用區塊鏈為基礎之名譽系統能有效實作，並且能有效進行導入。

關鍵字

區塊鏈 ； 名譽系統 ； 聯盟鏈 ； 以太坊 ； 智能合約

並列摘要

Reputation has been a very important role in both people and businesses. The rewards of having a good reputation can provide companies with higher incomes, better business relationships and more potential opportunities. According to the 2016 survey, 74% of potential customers said that positive reviews will help the companies to get more trust. With the popularity of the Internet, the reputation systems can be built everywhere. How to build a high sense of trust and defense all kinds of attacks will be an important issue facing today's reputation system.
With the rise of blockchain technology, many people have begun to explore whether the blockchain and reputation system can be further combined to achieve mutual benefit. The goal of this thesis is to discuss the advantages and disadvantages of the reputation system and blockchain technology. We hope that the blockchain based reputation system can not only solve the attacks that the reputation system has been facing, but also improve one of the problems that blockchain technology has been facing, which is the problem of off-chain activities. Blockchain technology performs well on the chain, but it’s hard to react to the off-chain activities. This thesis uses the Ethereum with Smart Contract to actually implements a reputation system, which we hope to would be helpful for future companies to import.
There are three research results. First, for the reputation system, the use of blockchain technology can effectively enhance its trust, and also effectively defense the current attacks. Second, for blockchain technology, building a reputation system on its foundation can effectively improve one of the blockchain’s problems, which is the difficulty in tracking off-chain activities. Third, for the enterprise, the reputation system based on the blockchain can be effectively implemented and can be effectively imported.

並列關鍵字

Blockchain ； Reputation System ； Consortium Chain ； Ethereum ； Smart Contract

參考文獻

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