论文标题
无用工作的证明 - 无用的无用的矿业结果和负面结果
Proofs of Useless Work -- Positive and Negative Results for Wasteless Mining Systems
论文作者
论文摘要
如今，包括比特币在内的许多区块链系统都依靠工作证明（POW）。工作证明对于加密货币的耐受性和安全性至关重要。使用POW时的假设是，在生成有效块之前，平均需要进行大量反复试验。关于这种系统提出的主要问题之一是在“毫无意义”问题上“浪费”能量的固有需求。实际上，据信比特币系统比几个小国消耗更多的电力。 在这项工作中，我们正式定义了无浪费的POW系统所需的三个属性：（1）解决“有意义的”问题（2）有效地解决它们，并且（3）对双期攻击进行安全保护。这些属性旨在为解决问题创造一个开放市场，在该市场中，矿工以最有效的方式为问题提供解决方案（无用）。该系统的安全源于对这些问题的解决方案的需求所产生的经济激励措施。 我们分析这些属性，并推断必须适用于此类POW系统的约束。在我们的主要结果中，我们得出的结论是，在现实的假设下，允许的问题必须是耐药的功能，以确保系统安全有效。
Many blockchain systems today, including Bitcoin, rely on Proof of Work (PoW). Proof of work is crucial to the liveness and security of cryptocurrencies. The assumption when using PoW is that a lot of trial and error is required on average before a valid block is generated. One of the main concerns raised with regard to this kind of system is the inherent need to "waste" energy on "meaningless" problems. In fact, the Bitcoin system is believed to consume more electricity than several small countries. In this work we formally define three properties that are necessary for wasteless PoW systems: (1) solve "meaningful" problems (2) solve them efficiently and (3) be secure against double-spend attacks. These properties aim to create an open market for problem-solving, in which miners produce solutions to problems in the most efficient way (wasteless). The security of the system stems from the economical incentive created by the demand for solutions to these problems. We analyze these properties, and deduce constraints that must apply to such PoW systems. In our main result, we conclude that under realistic assumptions, the set of allowed problems must be preimage resistant functions in order to keep the system secure and efficient.
