Design of Secure Sharing Scheme Based on Smart Contracts: Case Study on Home Sharing

The sharing economy is a system in which fixed resources are shared to increase their utility, and has disrupted a number of consumer markets for both enterprises and individuals. However, because payments for services on a sharing economy platform are usually conducted by banks and trusted third parties, these third-party platforms may become a single point of failure or compromise user privacy. In a previous study, a privacy mechanism that disrupts the contact between users and asset owners was proposed, which ensures fairness between the participants of a transaction. However, it does not use the automation provided by smart contracts in the design of conditionally triggered transactional agreements for each phase of a sharing-economy transaction (i.e., the initialization, registration, matching, and transaction phases), which would further enhance the transactional security and user privacy. To address this shortcoming, we designed a smart contract-based home sharing scheme. The features of this scheme are as follows: (1) A self-certification mechanism is used to enhance the level of security. (2) Contract functions are used to automatically resolve transactional conflicts and minimize the participation from third parties. (3) Blind signing is used in the transaction stage to preserve the confidentiality of personal information, and thus ensure the privacy of the transaction.

關鍵字

Home Sharing ； Smart Contracts ； Self-certification ； Blind Signing

並列摘要

共享經濟是透過分享的方式使閒置資源的運用更為便利，顛覆了許多企業與個人的消費模式。惟現行共享經濟平台藉由銀行及可信任第三方進行支付，衍生出許多問題，例如可信任的第三方平台單點故障及缺乏用戶隱私等。以往研究中曾提出透過打破使用者與財產擁有者之間的聯繫來保護隱私，而且確保參與交易的各方之間的公平性，惟未結合智慧合約的自動化流程管理，設計從部署至交易過程條件觸發之交易協定，進一步提升交易之安全性及使用者之隱私性。因此，本研究之目的，在於設計一套基於智慧合約的房屋共享方案。其具體貢獻包括：（1）藉由自我認證機制來強化安全性。（2）透過合約函式自動解決交易衝突，以降低第三方之參與。（3）於交易階段使用盲簽密技術強化個人資訊保密，以保障交易隱私性。