论文标题
加密和财务公平
Cryptographic and Financial Fairness
论文作者
论文摘要
多方计算的最新趋势是通过货币惩罚来实现加密公平，即每个诚实的玩家要么获得输出或以加密货币形式获得补偿。我们开创了另一种公平，财务公平性，更接近金融交易的现实估值。从直觉上讲，如果净现在参与成本（现金流入的总价值较少现金流出，相对折现率的加权）对于所有诚实参与者来说都是相同的，即使某些当事方作弊，罚款方案在财务上是公平的。 我们正式定义了这个概念，根据游戏理论显示了几个不可能的结果，并分析（缺乏）财务公正性的实际效果，如果一个人使用彭博社的深色池交易来运行真实的协议。 例如，我们表明，梯子协议（加密14）及其变体（CCS'15和CCS'16）在理论上和实践中都无法实现财务上的公平性，而Kumaresan和Bentov（CCS'14）的惩罚方案（CCS'14）以及Baum，Baum，Baum，David and David和Dowsley（David and Dowsley（FC'20））都是金融公平的。 此版本包含正式的定义，详细的安全性证明，演示和附录中的实验数据。
A recent trend in multi-party computation is to achieve cryptographic fairness via monetary penalties, i.e. each honest player either obtains the output or receives a compensation in the form of a cryptocurrency. We pioneer another type of fairness, financial fairness, that is closer to the real-world valuation of financial transactions. Intuitively, a penalty protocol is financially fair if the net present cost of participation (the total value of cash inflows less cash outflows, weighted by the relative discount rate) is the same for all honest participants, even when some parties cheat. We formally define the notion, show several impossibility results based on game theory, and analyze the practical effects of (lack of) financial fairness if one was to run the protocols for real on Bitcoin using Bloomberg's dark pool trading. For example, we show that the ladder protocol (CRYPTO'14), and its variants (CCS'15 and CCS'16), fail to achieve financial fairness both in theory and in practice, while the penalty protocols of Kumaresan and Bentov (CCS'14) and Baum, David and Dowsley (FC'20) are financially fair. This version contains formal definitions, detailed security proofs, demos and experimental data in the appendix.
