Collaborative Research: SaTC: CORE: Small: Accountability for Central Bank Digital Currency

今天，全球几家中央银行正在积极探索中央银行数字货币（CBDC）的部署。A（零售）CBDC是中央银行的货币，它(A)本质上是数字的，(b)公众可以广泛获得。cbdc的一些拟议好处包括在实施货币政策方面具有更大的灵活性，改善了金融包容性，以及以更低的费用提高了资金转移效率。然而，许多人担心cbdc将使网络犯罪分子更容易攻击金融系统。例如，CBDC可能会使恶意用户更容易通过在两个地方使用相同的数字代币来窃取中央银行的资金。这些安全问题通常通过算法和加密技术的进步来解决，但通常以严重的性能下降为代价。该项目的新颖之处在于探索CBDC安全的另一种方法：问责制。也就是说，如果网络犯罪分子在CBDC中行为不端，底层协议应该足够丰富，能够从密码学上证明谁是罪魁祸首。该项目更广泛的意义和重要性在于，它可以影响设计安全的cbdc的设计和开发。该项目研究了规范CBDC的共识层和应用层的问责制。在每一层，该项目首先修改现有算法（例如，共识，反洗钱限制），以提供可证明的问责制。这些修改需要在分布式系统和/或密码学方面进行创新。该项目还从理论和实践两方面研究了问责制的基本绩效成本。这些算法的性能成本在实现中进行了经验评估，这些算法与OpenCBDC集成在一起，OpenCBDC是一种开源的CBDC实现，由麻省理工学院数字货币计划与波士顿联邦储备银行合作开发和维护。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Today, several central banks worldwide are actively exploring the deployment of a centrally-banked digital currency (CBDC). A (retail) CBDC is central bank money that is (a) digital in nature, and (b) widely accessible to the public. Some of the proposed benefits of CBDCs include greater flexibility in implementing monetary policy, improved financial inclusion, and more efficient money transfers at lower fees. However, many fear that CBDCs will make it easier for cybercriminals to attack the financial system. For example, a CBDC might make it easier for malicious users to steal central bank money by spending the same digital token in two places. These security concerns are commonly addressed with algorithmic and cryptographic advances, often at the cost of serious performance degradations. The project’s novelty lies in exploring an alternate approach to CBDC security: accountability. That is, if a cybercriminal misbehaves in a CBDC, the underlying protocol should be rich enough to prove, cryptographically, who was the culprit. The project’s broader significance and importance is that it can impact the design and development of secure-by-design CBDCs.  The project studies accountability at the consensus and application layers of a canonical CBDC. At each layer, the project first modifies existing algorithms (e.g., consensus, anti money laundering restrictions) to provide provable accountability. These modifications require innovations in distributed systems and/or cryptography. The project also studies the fundamental performance costs of accountability, both theoretically and in practice. The performance cost of these algorithms is evaluated empirically in implementations, which are integrated with OpenCBDC, an open-source CBDC implementation that was developed and maintained by the MIT Digital Currency Initiative in collaboration with the Federal Reserve Bank of Boston.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.