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

如今，全球多家中央银行正在积极探索部署中央银行数字货币（CBDC）。（零售）CBDC是央行货币，（a）本质上是数字货币，（B）公众可以广泛获取。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，改善金融包容性，以及以更低的费用更有效地进行资金转移。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花费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，但往往以严重的性能下降为代价。该项目的新奇之处在于探索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，可以通过加密方式证明谁是罪魁祸首。该项目更广泛的意义和重要性在于，它可以影响安全设计CBDC的设计和开发。 该项目研究规范CBDC的共识和应用层的问责制。在每一层，项目首先修改现有的算法（例如，共识，反洗钱限制），以提供可证明的问责制。这些修改需要分布式系统和/或密码学的创新。该项目还从理论和实践两方面研究问责制的基本绩效成本。这些算法的性能成本在实施中进行了经验评估，这些实施与OpenCBDC集成，OpenCBDC是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的开源CBDC实施。该奖项反映了NSF的法定使命，并被认为值得通过使用基金会的智力价值和更广泛的影响审查标准进行评估来支持。

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.