Asset custody is a core financial service in which the custodian holds in-safekeeping assets on behalf of the client. Although traditional custody service is typically endorsed by centralized authorities, decentralized custody scheme has become technically feasible since the emergence of digital assets, and furthermore, it is greatly needed by new applications such as blockchain and DeFi (Decentralized Finance). In this work, we propose a framework of decentralized asset custody scheme that is able to support a large number of custodians and safely hold customer assets of multiple times the value of the total security deposit. The proposed custody scheme distributes custodians and assets into many custodian groups via combinatorial designs, where each group fully controls the assigned assets. Since every custodian group is small, the overhead cost is significantly reduced. The liveness is also improved because even a single alive group would be able to process transactions. The security of this custody scheme is guaranteed under the rational adversary model, such that any adversary corrupting a bounded fraction of custodians cannot move assets more than the security deposit paid. We further analyze the security and performance of our constructions from both theoretical and experimental sides and give explicit examples with concrete numbers and figures for a better understanding of our results.
翻译:资产保管是一项核心财务服务,由保管人代表客户保管资产。虽然传统的保管服务通常得到中央机关的认可,但自数字资产出现以来,分散保管计划在技术上已经变得技术上可行,此外,新的应用程序,如块链和分权金融(分权金融)非常需要这种制度。在这项工作中,我们提议了一个分散的资产保管计划框架,它能够支持大量保管人,安全地持有比所付保证金价值多倍的客户资产。拟议的保管计划通过组合设计将保管人和资产分配给许多保管团体,每个团体都完全控制所分配的资产。由于每个保管人团体规模小,管理费用也大大降低。生活状况也得到改善,因为即使是一个活着的团体也能处理交易。这种保管计划的安全性得到合理的对抗模式的保障,因此任何敌对方腐蚀受约束的保管人的资产都无法比所付保证金多动得更多。我们从理论和实验的角度进一步分析我们的工程的安全和业绩,并给出具体数字和数字,以便更好地了解我们的结果。