SaTC: CORE: Small: Collaborative: Proof of Work Without All the Work

工作量证明（PoW）是一种经济工具，通过要求参与者执行可验证的工作（通常是通过解决计算难题）来阻止网络攻击。不幸的是，有一个重要的障碍阻碍了PoW的广泛应用：PoW是昂贵的。该项目旨在显著降低PoW方案的成本，从而扩大其效用。我们的通用模型涉及一个由好的和坏的标识符（id）组成的分布式系统。好的id有两个目标：(1)确保有限资源的公平共享；(2)安全地进行分布式计算。恶意id由攻击者控制，攻击者拥有一定比例的计算资源，并试图破坏这些目标。一个重要的安全目标是开发一种机制，在产生带宽和计算成本（随着攻击的规模而增加）的同时保持这些目标。也就是说，当没有攻击时，成本很低；相反，当发生攻击时，良好id的成本与攻击者的成本成正比增长。该项目专注于分布式算法的设计：(i)在具有良好id的情况下容忍大型攻击，并且花费渐近少于攻击者；（ii）处理参与者自私但理性的情境；（iii）通过低状态和带宽成本的抗攻击覆盖设计快速和健壮的扩散协议。该项目为本科生和代表性不足的学生提供研究经验，将最先进的成果纳入课程开发，并为网络安全研究人员建立一个研讨会场所，以分享他们的发现。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。

Proof-of-work (PoW) is an economic tool used to deter network attacks by requiring participants to perform verifiable work, typically by solving computational puzzles. Unfortunately, there is a significant barrier impeding wide-spread applicability: PoW is expensive. This project aims to significantly reduce the cost of PoW schemes, and thereby broaden their utility. Our general model concerns a distributed system consisting of good and bad identifiers (IDs). The good IDs have two goals: (1) ensure fair sharing of a limited resource; and (2) securely perform distributed computations. The bad IDs are controlled by an attacker who possesses a constant fraction of the computational resources, and tries to subvert these goals. An important security objective is to develop mechanisms that preserve these goals while incurring bandwidth and computational costs that scale with the magnitude of an attack. That is, when there is no attack, costs are low; conversely, when there is an attack, the good IDs' cost grows commensurately with the attacker's cost. This project focuses on the design of distributed algorithms for: (i) tolerating large attacks while having good IDs spend asymptotically less than the attacker; (ii) handling a setting where participants are selfish but rational; and (iii) designing fast and robust diffuse protocols via attack-resistant overlays with low state and bandwidth costs. The project provides research experience for undergraduate and underrepresented students, incorporates state-of-the-art results into course development, and establishes a workshop venue for cybersecurity researchers to share their findings.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.